SOMAPL13 — Practice Exam
100 questions across 9 objectives. Click any section in the sidebar to jump
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2581 — Medical Vocabulary
10 questions covering prefixes, roots, and suffixes related to cell biology
Q1MC
What does the prefix "hypo-" mean, as used in the term "hypotonic"?
A. Above or in excess of normal
B. Below or deficient
C. Equal or balanced
D. Inside or within
Correct — "Hypo-" means below or deficient. A hypotonic solution has a lower solute concentration than the cell interior, causing water to flow in.
Incorrect — The correct answer is B. "Hypo-" means below or deficient. Contrast with "hyper-" (above/excess) and "iso-" (equal).
Q2MC
Which term correctly uses the root "osmos" (meaning thrust or push)?
A. Mitosis
B. Cytoplasm
C. Osmosis
D. Endocytosis
Correct — Osmosis derives from "osmos" (thrust), describing the forceful movement of water molecules across a selectively permeable membrane.
Incorrect — The correct answer is C. Osmosis uses the root "osmos" (thrust). Mitosis uses "mitos" (thread), cytoplasm uses "cyto-" (cell), and endocytosis uses "endo-" (inside).
Q3MC
The root word "phago-" means "to eat." Phagocytosis is therefore best described as:
A. Cell drinking — uptake of small fluid-filled vesicles
B. Cell splitting — division of the cytoplasm
C. Cell eating — engulfment of solid particles into the cell
D. Cell death — genetically programmed self-destruction
Correct — Phagocytosis (phago- = to eat, cyto- = cell) is "cell eating" — specialized cells extend pseudopodia to engulf solid material such as bacteria or debris.
Incorrect — The correct answer is C. Phago- means to eat; phagocytosis is "cell eating." Pinocytosis (pinein = to drink) is cell drinking.
Q4MC
In the term "apoptosis," the root "ptosis" means:
A. Division or splitting
B. Eating or engulfing
C. A falling away
D. Thrusting or pushing
Correct — "Ptosis" means a falling away. Apoptosis (apo- = separated from + ptosis = a falling) is the genetically controlled death and "falling away" of cells.
Incorrect — The correct answer is C. "Ptosis" means a falling away. Apoptosis describes cells that are programmed to fall away and die.
Q5FITB
The root word "chroma" (as in chromosome) means ___.
Correct — "Chroma" means color. Chromosomes are so named because they stain intensely with colored dyes during microscopy, making them visible as distinctly colored bodies.
Incorrect — The correct answer is "color." Chroma = color. Chromosomes literally means "colored bodies" because they absorb dye strongly during microscopy.
Q6MC
The prefix "endo-" in "endocytosis" means:
A. Outside
B. After or following
C. Inside
D. Between
Correct — "Endo-" means inside. Endocytosis moves material inside the cell. Its opposite, "exo-" (outside), describes exocytosis, which moves material outside.
Incorrect — The correct answer is C. "Endo-" means inside. Compare: endocytosis (into the cell) vs exocytosis (out of the cell).
Q7MC
The prefix "inter-" as used in "interphase" means:
A. Before
B. After
C. Between
D. Apart
Correct — "Inter-" means between. Interphase is the interval between cell divisions — the period when the cell performs its normal functions.
Incorrect — The correct answer is C. "Inter-" means between. Interphase is the time between active divisions of the cell cycle.
Q8MC
The root "mitos" as in "mitosis" means:
A. Division
B. Thread
C. Granule
D. Color
Correct — "Mitos" means thread. During mitosis, condensed chromosomes appear as thread-like structures under the microscope, which is how the process got its name.
Incorrect — The correct answer is B. "Mitos" means thread. Compare: mitochondrion = mitos (thread) + chondrion (granule).
Q9SATA
Select ALL terms whose prefix or root correctly matches its definition below. (Select all that apply.)
Hint: More than one answer may be correct.
Correct — Iso- = equal, kinesis = motion, soma = body. Hyper- means ABOVE or excess (not below — that is hypo-).
Incorrect — The correct selections are iso- (equal), kinesis (motion), and soma (body). Hyper- means ABOVE or excess; hypo- means below.
Q10MC
The word "pseudopod" is built from "pseudo-" (false) and "podon" (foot). A pseudopod is therefore:
A. A type of membrane channel protein
B. A ribosome attached to the rough ER
C. A cytoplasmic extension that acts as a false foot during phagocytosis
D. A flagellum that propels sperm cells
Correct — Pseudopodia (pseudo- = false, podon = foot) are cytoplasmic extensions that surround a foreign object during phagocytosis. They act like false feet to engulf the target.
Incorrect — The correct answer is C. Pseudo- = false, podon = foot. Pseudopodia are false feet — cytoplasmic extensions used in phagocytosis.
2582 — Cell Theory
8 questions covering the four main points of cell theory and microscopy methods
Q11SATA
Select ALL four statements that are main points of the cell theory as presented in the textbook.
Correct — All four are the exact points of the cell theory: building blocks of life, smallest functioning units, produced from preexisting cells, and each maintaining homeostasis.
Incorrect — All four options are correct. The cell theory has exactly four main points, and all four are listed here. You must select all four.
Q12MC
According to the cell theory, new cells arise from:
A. Chemical synthesis in the extracellular environment
B. Spontaneous assembly of organic molecules
C. The division of preexisting cells
D. Transcription of DNA within the Golgi apparatus
Correct — Cell theory states cells are produced through division of preexisting cells. This is the foundational principle that overturned the earlier idea of spontaneous generation.
Incorrect — The correct answer is C. Cell theory explicitly states cells arise from division of preexisting cells — not from spontaneous generation or chemical synthesis.
Q13MC
Which statement does NOT belong as a main point of the cell theory?
A. Each cell maintains homeostasis
B. Cells are the building blocks of all plants and animals
C. All cells contain a nucleus that stores genetic information
D. Cells are the smallest functioning units of life
Correct — "All cells contain a nucleus" is NOT a main point of cell theory. In fact, it is false — red blood cells lack a nucleus. The four main points concern building blocks, smallest units, division from preexisting cells, and homeostasis.
Incorrect — The correct answer is C. "All cells contain a nucleus" is not part of the cell theory and is factually incorrect (mature red blood cells have no nucleus). The four real points are: building blocks, smallest units, arise from preexisting cells, maintain homeostasis.
Q14MC
Cytology is defined as:
A. The study of tissues and their organization
B. The study of the structure and function of cells
C. The study of organ system physiology
D. The study of heredity and gene expression
Correct — Cytology (cyto- = cell, -logy = study of) is the study of cell structure and function. The study of tissues is histology.
Incorrect — The correct answer is B. Cytology = study of cells. Histology = study of tissues. Do not confuse these two.
Q15MC
Which type of micrograph provides a three-dimensional surface view of cells rather than a detailed internal cross-section?
A. Light micrograph (LM)
B. Transmission electron micrograph (TEM)
C. Scanning electron micrograph (SEM)
D. Confocal micrograph
Correct — SEM provides a 3D surface view of cells or extracellular structures, with less magnification than TEM. TEM provides detailed 2D sectional views of internal structures.
Incorrect — The correct answer is C. SEM = 3D surface view. TEM = 2D detailed internal section. LM = standard glass lens microscopy up to ~1,000× magnification.
Q16MC
A transmission electron micrograph (TEM) is best used for:
A. Viewing the three-dimensional surface of a cell
B. Revealing fine details of cell membranes and intracellular structures in thin sections
C. Observing living cells in real time at low magnification
D. Producing photographs of tissue at approximately 160× magnification
Correct — TEM uses a focused beam of electrons on very thin sections to reveal fine internal details of cell membranes and intracellular structures — far beyond what light microscopy can resolve.
Incorrect — The correct answer is B. TEM = detailed 2D sectional views of internal structures. Option A describes SEM. Option D describes routine light micrography.
Q17MC
Light microscopy magnifies cellular structures approximately how many times?
A. 100 times
B. 500 times
C. 1,000 times
D. 10,000 times
Correct — Light microscopy using a series of glass lenses can magnify cellular structures about 1,000 times. Electron microscopy achieves far greater magnification.
Incorrect — The correct answer is C. Light microscopy magnifies approximately 1,000 times. Electron microscopy achieves significantly higher magnification.
Q18FITB
A photograph taken through a light microscope is called a light ___.
Correct — A light micrograph (LM) is any photograph taken through a light microscope. The abbreviation LM followed by a magnification number (e.g., LM ×160) appears on images in the textbook.
Incorrect — The correct answer is micrograph. A light micrograph (LM) is a photograph taken through a light microscope.
2583 — The Plasma Membrane
12 questions covering membrane functions, lipids, proteins, and carbohydrates
Q19MC
Which of the following is NOT a general function of the plasma membrane?
A. Physical isolation of cell contents from extracellular fluid
B. Regulation of exchange with the environment
C. Production of ATP through aerobic metabolism
D. Structural support for tissues
Correct — ATP production through aerobic metabolism is a function of the mitochondria, not the plasma membrane. The four functions of the plasma membrane are: physical isolation, regulation of exchange, sensitivity to the environment, and structural support.
Incorrect — The correct answer is C. ATP production occurs in mitochondria. The plasma membrane's four functions are: physical isolation, regulation of exchange, environmental sensitivity, and structural support.
Q20MC
In the phospholipid bilayer, the hydrophobic fatty acid tails are oriented:
A. Facing outward toward the extracellular fluid
B. On the surface of the membrane in contact with the cytosol
C. Inward, facing each other and away from water
D. Scattered randomly throughout the membrane
Correct — The hydrophobic (water-fearing) fatty acid tails point inward, away from the aqueous environments on either side of the membrane. The hydrophilic (water-loving) heads face outward toward the extracellular fluid and cytosol.
Incorrect — The correct answer is C. Hydrophobic tails point inward (away from water). Hydrophilic heads face outward (toward water on both sides). This arrangement is the basis for the membrane's selective permeability.
Q21SATA
Which substances can cross the phospholipid bilayer directly, without requiring channel or carrier proteins?
Correct — O₂, CO₂, and steroids are lipid-soluble and cross the lipid bilayer directly. Sodium ions are charged (not lipid-soluble) and must pass through channel proteins.
Incorrect — O₂, CO₂, and steroids (lipid-soluble) cross directly through the bilayer. Sodium ions and other charged/water-soluble compounds cannot penetrate the lipid layer and require channel proteins.
Q22MC
Transmembrane proteins are defined as membrane proteins that:
A. Float freely in the extracellular fluid surrounding the cell
B. Are found only on the inner surface of the plasma membrane
C. Span the width of the plasma membrane one or more times
D. Are exclusively involved in carbohydrate synthesis
Correct — Transmembrane proteins are the most common type of membrane protein. They span the full width of the membrane one or more times and can interact with both the extracellular fluid and the cytoplasm.
Incorrect — The correct answer is C. Transmembrane proteins span the entire width of the membrane. Other proteins may be partially embedded or loosely attached to one surface.
Q23SATA
Select ALL recognized functional classes of membrane proteins listed in the textbook.
Correct — Receptor, channel, and anchoring proteins are all recognized functional classes. "Respiratory proteins generating ATP" is a function of mitochondrial enzymes, not plasma membrane proteins.
Incorrect — Receptor, channel, and anchoring proteins are correct. The six classes are: receptors, channels, carriers, enzymes, anchors, and recognition proteins (identifiers). ATP generation by respiratory proteins is a mitochondrial function.
Q24MC
Glycoproteins and glycolipids on the outer surface of the plasma membrane function primarily as:
A. Ion channels that allow charged particles to cross the membrane
B. Hydrophobic barriers that block water-soluble molecules
C. Cell lubricants, adhesives, extracellular receptors, and immune recognition markers
D. Enzymes that generate ATP on the extracellular surface
Correct — Carbohydrate chains on glycoproteins and glycolipids function as lubricants and adhesives, act as receptors for extracellular compounds, and form a recognition system that prevents the immune system from attacking the body's own tissues.
Incorrect — The correct answer is C. Glycoproteins/glycolipids act as lubricants, adhesives, extracellular receptors, and immune self-recognition markers. They are not ion channels or ATP-generating enzymes.
Q25MC
A plasma membrane described as "selectively permeable" means it:
A. Allows all substances to pass through with equal ease
B. Blocks the passage of all substances equally
C. Permits free passage of some materials while restricting others
D. Is permeable only to gases
Correct — Selectively permeable means some substances cross freely while others cannot. What can pass depends on size, electrical charge, molecular shape, and lipid solubility.
Incorrect — The correct answer is C. Selectively permeable means passage is selective — some substances cross freely, others are blocked. Not all, not none, not only gases.
Q26MC
Channel proteins in the plasma membrane primarily allow passage of:
A. Large lipid-soluble molecules such as steroids
B. Large organic molecules such as glucose and proteins
C. Water, small ions such as sodium and potassium, and small water-soluble molecules
D. Viruses and bacteria through receptor-mediated endocytosis
Correct — Channel proteins form pores (~0.8 nm diameter) that allow water, small ions (Na⁺, K⁺), and small water-soluble molecules to pass. Glucose is too large for channels and requires carrier proteins instead.
Incorrect — The correct answer is C. Channel proteins allow water, small ions, and small water-soluble molecules through. Steroids cross through the lipid layer. Glucose needs carrier proteins — it is too large for membrane channels.
Q27MC
Which component of the plasma membrane is primarily responsible for creating a selective physical barrier between the cell and its environment?
A. Recognition proteins on the outer surface
B. Channel proteins spanning the membrane
C. The phospholipid bilayer
D. Carbohydrate chains on glycoproteins
Correct — The hydrophobic lipid tails of the phospholipid bilayer will not associate with water or charged molecules, making the bilayer the primary selective physical barrier. Ions and water-soluble compounds cannot cross the lipid layer unaided.
Incorrect — The correct answer is C. The phospholipid bilayer creates the primary barrier. Its hydrophobic core prevents charged and water-soluble molecules from crossing without the aid of channel or carrier proteins.
Q28FITB
Carbohydrate chains attached to membrane proteins create molecules called ___.
Correct — Glycoproteins are carbohydrate-protein complexes on the outer membrane surface. Similarly, carbohydrates attached to lipids form glycolipids.
Incorrect — The correct answer is glycoproteins. Carbohydrate + protein = glycoprotein. Carbohydrate + lipid = glycolipid.
Q29MC
The "structural support" function of the plasma membrane refers to:
A. Synthesis of structural proteins such as collagen
B. Specialized connections between membranes that give tissues a stable structure
C. The rigidity of the phospholipid bilayer preventing membrane deformation
D. The role of microtubules in anchoring the nucleus
Correct — Structural support means specialized connections between plasma membranes, or between membranes and extracellular materials, give tissues a stable structure. This is an intercellular adhesion function.
Incorrect — The correct answer is B. Structural support refers to specialized connections between membranes or between membranes and extracellular materials that stabilize tissue architecture. The membrane itself is not rigid — it is fluid.
Q30SATA
Which of the following membrane protein types would be most involved when the immune system evaluates whether a cell belongs to the body?
Correct — Recognition proteins (identifiers) identify a cell as self or nonself, normal or abnormal, to the immune system. One major group is the major histocompatibility complex (MHC).
Incorrect — Recognition proteins (identifiers) are the class responsible for immune self-recognition. The MHC is the primary example. Carrier, channel, and anchoring proteins perform different functions unrelated to immune identification.
2584 — Membrane Transport Mechanisms
15 questions covering diffusion, osmosis, filtration, active transport, and vesicular transport
Q31MC
Diffusion moves dissolved molecules:
A. From low concentration to high concentration
B. From high concentration to low concentration
C. Against the concentration gradient using ATP
D. Only through channel proteins, regardless of gradient
Correct — Diffusion is the net movement of molecules from high to low concentration — "downhill," or down the concentration gradient. No energy is required. Molecules eventually distribute evenly, eliminating the gradient.
Incorrect — The correct answer is B. Diffusion always moves substances from high to low concentration (down the gradient). Movement against a gradient requires active transport and ATP.
Q32MC
Osmosis is specifically defined as:
A. The movement of any solute molecule across any biological membrane
B. The diffusion of water molecules across a selectively permeable membrane
C. The pressure-driven movement of water and solutes by the heartbeat
D. Carrier-mediated water transport requiring ATP
Correct — Osmosis is specifically the diffusion of water (not just any solute) across a selectively permeable membrane. The membrane must be freely permeable to water but not freely permeable to the solutes.
Incorrect — The correct answer is B. Osmosis = diffusion of water specifically. Option C describes filtration (driven by hydrostatic/blood pressure). Options A and D are incorrect definitions.
Q33MC
A red blood cell placed in a hypotonic solution will:
A. Lose water by osmosis and shrivel — a process called crenation
B. Remain unchanged because there is no concentration gradient
C. Gain water by osmosis and may swell and lyse — a process called hemolysis
D. Actively pump out the excess solute to maintain equilibrium
Correct — A hypotonic solution has less solute than the cell interior. Water flows INTO the cell by osmosis (toward higher solute concentration). The cell swells and may burst — called hemolysis in red blood cells.
Incorrect — The correct answer is C. Hypotonic = less solute outside. Water moves in (toward higher internal solute). Cell swells → hemolysis. Crenation occurs in HYPERTONIC solutions (water moves out).
Q34MC
Normal saline is a 0.9% NaCl solution used clinically for fluid replacement because it:
A. Contains enough glucose to meet cellular energy needs
B. Is hypertonic, pulling fluid from swollen tissues
C. Approximates the normal osmotic concentration of extracellular fluid, making it essentially isotonic to body cells
D. Is the minimum concentration of NaCl required to prevent cell lysis
Correct — Normal saline matches the osmotic concentration of extracellular fluid because sodium and chloride are the most abundant ions in that compartment. Little net ion movement occurs, making it essentially isotonic to body cells.
Incorrect — The correct answer is C. Normal saline is isotonic — it matches the normal osmotic concentration of extracellular fluid. It does not contain glucose, is not hypertonic, and is not the minimum anti-lysis concentration.
Q35MC
Filtration across capillary walls in the body is driven by:
A. Carrier proteins consuming ATP energy
B. Concentration gradients of solutes
C. Osmotic pressure drawing water toward cells
D. Hydrostatic (blood) pressure generated by the heart
Correct — Filtration is driven by hydrostatic pressure — blood pressure created by the heart forcing blood through vessels. This pushes water and small dissolved nutrients across capillary walls into tissues and through kidney filtration membranes to produce urine.
Incorrect — The correct answer is D. Filtration = hydrostatic pressure (blood pressure from the heart). No ATP, no concentration gradient, no osmotic pressure drives filtration.
Q36MC
Facilitated diffusion differs from simple diffusion in that facilitated diffusion:
A. Moves substances against their concentration gradient
B. Requires ATP energy to function
C. Uses carrier proteins and has a maximum (saturable) transport rate
D. Does not follow a concentration gradient
Correct — Facilitated diffusion uses specific carrier proteins and is therefore saturable — once all carriers are occupied, increasing solute concentration produces no further increase in transport rate. It still moves substances down their gradient without ATP.
Incorrect — The correct answer is C. Facilitated diffusion uses carrier proteins and is saturable. It is still passive (no ATP, still down the gradient). What distinguishes it from simple diffusion is the carrier protein requirement and the rate ceiling.
Q37SATA
Select ALL passive transport mechanisms (no ATP required).
Correct — Simple diffusion, osmosis, and facilitated diffusion are all passive (no ATP required). Active transport requires ATP to move substances against concentration gradients.
Incorrect — The passive mechanisms are simple diffusion, osmosis, and facilitated diffusion. Active transport requires ATP and is NOT passive. Vesicular transport (endocytosis/exocytosis) is also always active.
Q38MC
For each ATP consumed, the sodium-potassium exchange pump moves:
A. 2 Na⁺ out of the cell and 3 K⁺ into the cell
B. 3 Na⁺ out of the cell and 2 K⁺ into the cell
C. Equal numbers of Na⁺ out and K⁺ in
D. 1 Na⁺ out of the cell and 1 K⁺ into the cell
Correct — 3 Na⁺ are ejected out of the cell and 2 K⁺ are reclaimed into the cell per ATP consumed. This ratio is essential to know — it maintains the high Na⁺ outside / high K⁺ inside gradient.
Incorrect — The correct answer is B. The sodium-potassium pump moves 3 Na⁺ OUT and 2 K⁺ IN per ATP. "3 out, 2 in" is a high-yield fact.
Q39MC
The sodium-potassium exchange pump may use up to what percentage of a resting cell's total ATP production?
A. 5–10%
B. 15–20%
C. Up to 40%
D. Over 70%
Correct — The sodium-potassium exchange pump may consume up to 40% of the ATP produced by a resting cell. This illustrates how energetically expensive it is to maintain ion gradients across the plasma membrane.
Incorrect — The correct answer is C. Up to 40% of a resting cell's ATP may be consumed by the sodium-potassium pump alone — a reflection of how critical and energy-intensive ion gradient maintenance is.
Q40MC
Receptor-mediated endocytosis is more selective than pinocytosis because:
A. It requires significantly more ATP energy per vesicle
B. It is performed only by immune cells
C. It uses specific membrane receptors that bind only to designated target molecules (ligands)
D. It produces larger vesicles that contain more material
Correct — Receptor-mediated endocytosis uses specific receptor proteins that bind to specific target molecules called ligands. Only the targeted molecule enters. Pinocytosis forms vesicles filled with any extracellular fluid — no receptor specificity.
Incorrect — The correct answer is C. The defining feature of receptor-mediated endocytosis is receptor specificity — only molecules that bind to the specific receptor are taken in, making it highly selective compared to non-specific pinocytosis.
Q41MC
Phagocytosis is primarily performed by:
A. All body cells equally, as a basic survival function
B. Liver cells and pancreatic cells
C. Specialized cells such as white blood cells and macrophages that protect tissues
D. Cells of the smooth endoplasmic reticulum
Correct — Phagocytosis is performed only by specialized cells that protect tissues by engulfing bacteria, cell debris, and other abnormal materials — primarily white blood cells and macrophages. Most cells only display pinocytosis.
Incorrect — The correct answer is C. Most cells display pinocytosis, but phagocytosis is limited to specialized protective cells like white blood cells and macrophages.
Q42FITB
The term for "cell drinking" — formation of small vesicles filled with extracellular fluid — is ___.
Correct — Pinocytosis (pinein = to drink) is "cell drinking." It is nonselective — a groove in the plasma membrane pinches off to form vesicles filled with extracellular fluid. Common to all cells.
Incorrect — The correct answer is pinocytosis. Pinein = to drink. Pinocytosis = cell drinking (nonselective fluid uptake). Phagocytosis = cell eating (solid particle uptake by specialized cells).
Q43SATA
Select ALL three major types of endocytosis.
Correct — The three types of endocytosis are receptor-mediated endocytosis, pinocytosis, and phagocytosis. Exocytosis is the OPPOSITE — it moves material OUT of the cell.
Incorrect — The three types of endocytosis (into the cell) are: receptor-mediated endocytosis, pinocytosis, and phagocytosis. Exocytosis is vesicular transport OUT of the cell — it is not a form of endocytosis.
Q44MC
During exocytosis, what happens to a vesicle created inside the cell?
A. It fuses with a lysosome to digest its contents
B. It moves to the nucleus to deliver mRNA
C. It fuses with the plasma membrane and discharges its contents into the extracellular environment
D. It travels to the Golgi apparatus for further modification
Correct — In exocytosis, a vesicle formed inside the cell fuses with the plasma membrane and releases its contents outside the cell. This process secretes hormones, mucus, and eliminates waste from recycled organelles.
Incorrect — The correct answer is C. Exocytosis = vesicle fuses with plasma membrane → contents discharged outside. It is the functional reverse of endocytosis.
Q45MC
When all available carrier proteins are occupied during facilitated diffusion, further increasing extracellular solute concentration will:
A. Increase the rate of transport proportionally
B. Cause the cell to switch to active transport
C. Produce no further increase in transport rate
D. Cause the carrier proteins to function as channels instead
Correct — Once all carrier proteins are saturated, the transport rate cannot increase regardless of how much more solute is added. This saturation is a key characteristic that distinguishes facilitated diffusion from simple diffusion.
Incorrect — The correct answer is C. Facilitated diffusion saturates. Once all carriers are occupied, the maximum rate is reached and cannot be exceeded — unlike simple diffusion, which has no ceiling.
2585 — Organelles of a Typical Cell
18 questions covering membranous and nonmembranous organelles and their functions
Q46MC
Which organelle is responsible for producing approximately 95% of a cell's ATP?
A. Golgi apparatus
B. Smooth endoplasmic reticulum
C. Mitochondria
D. Peroxisomes
Correct — Mitochondria produce approximately 95% of the ATP a cell needs through aerobic metabolism (cellular respiration). The remaining ~5% comes from glycolysis in the cytosol.
Incorrect — The correct answer is C. Mitochondria produce ~95% of cellular ATP through aerobic metabolism. They are the powerhouses of the cell.
Q47MC
Compared to extracellular fluid, the cytosol of a typical cell contains:
A. Higher sodium ion (Na⁺) concentration and lower potassium ion (K⁺) concentration
B. Higher potassium ion (K⁺) concentration and lower sodium ion (Na⁺) concentration
C. Equal concentrations of Na⁺ and K⁺
D. Lower concentrations of all dissolved proteins
Correct — Cytosol has HIGH K⁺ and LOW Na⁺. Extracellular fluid has HIGH Na⁺ and LOW K⁺. The sodium-potassium pump actively maintains these opposing gradients.
Incorrect — The correct answer is B. Inside = high K⁺, low Na⁺. Outside = high Na⁺, low K⁺. This is maintained by the sodium-potassium exchange pump.
Q48MC
Microvilli are found on the exposed surfaces of cells such as intestinal and kidney cells primarily because they:
A. Generate coordinated beating movements to propel mucus
B. Anchor the cell firmly to neighboring cells
C. Increase membrane surface area available for absorption
D. Produce the spindle fibers needed for cell division
Correct — Microvilli are finger-shaped membrane projections that dramatically increase the surface area exposed to extracellular fluid, maximizing absorption. They are common in cells actively engaged in absorbing materials.
Incorrect — The correct answer is C. Microvilli increase surface area for absorption. Beating movements describe cilia. Anchoring is done by anchoring proteins. Spindle fibers come from centrioles.
Q49MC
Centrioles are composed of:
A. Actin microfilaments in a 9+2 arrangement
B. Microtubule doublets in a 9+2 arrangement
C. Microtubule triplets in a 9+0 arrangement
D. Intermediate filaments arranged in parallel bundles
Correct — Centrioles contain microtubule TRIPLETS in a 9+0 arrangement. Compare to cilia, which contain microtubule DOUBLETS in a 9+2 arrangement. Knowing both arrangements is high-yield for this exam.
Incorrect — The correct answer is C. Centrioles = microtubule TRIPLETS, 9+0 array. Cilia = microtubule DOUBLETS, 9+2 array. The structure differs between these two organelles.
Q50SATA
Select ALL cell types that lack centrioles and therefore CANNOT undergo mitotic cell division.
Correct — Mature red blood cells, skeletal muscle cells, cardiac muscle cells, and typical neurons lack centrioles and cannot divide. Liver cells retain centrioles and can divide (this is why the liver can regenerate).
Incorrect — Mature red blood cells, skeletal muscle cells, and cardiac muscle cells (plus typical neurons) lack centrioles and cannot divide. Liver cells retain centrioles and CAN divide. The textbook specifically names these four non-dividing cell types.
Q51MC
Cilia on respiratory tract epithelial cells function to:
A. Propel the epithelial cells through the respiratory mucus
B. Absorb nutrients from the mucus layer
C. Move mucus and trapped particles toward the throat by coordinated beating
D. Produce the mucus secreted into the airway
Correct — Cilia move the fluid or secretions past the stationary cell, not the cell itself. In the respiratory tract, coordinated ciliary beating sweeps mucus and trapped particles upward toward the throat, away from the delicate respiratory surfaces.
Incorrect — The correct answer is C. Cilia move material OVER the cell surface, not the cell itself. Flagella move the cell. Damage to respiratory cilia (e.g., from smoking) results in chronic cough and increased infections.
Q52FITB
Sperm cells are the only human cells that possess a ___ — an organelle that moves the cell itself through surrounding fluid.
Correct — Flagellum (plural: flagella). Sperm cells are the only human cells with a flagellum. If flagella are paralyzed or abnormal, the individual will be sterile because immobile sperm cannot reach and fertilize an egg.
Incorrect — The correct answer is flagellum. Only sperm cells have a flagellum in the human body. Cilia and flagella differ: cilia move fluid past a stationary cell; flagella move the cell itself.
Q53MC
Fixed ribosomes differ from free ribosomes in that fixed ribosomes are:
A. Scattered throughout the cytoplasm and release proteins into the cytosol
B. Attached to the rough endoplasmic reticulum; proteins they produce enter the ER for modification and export
C. Located within the nucleus to produce ribosomal RNA
D. Attached to the inner mitochondrial membrane to produce ATP
Correct — Fixed ribosomes are attached to the rough ER. Proteins made on fixed ribosomes are threaded into the ER, modified, and packaged for export. Free ribosomes in the cytoplasm produce proteins that remain within the cytosol.
Incorrect — The correct answer is B. Fixed = attached to rough ER; products exported. Free = scattered in cytoplasm; products stay in cytosol. Nucleoli produce rRNA — that is a different function.
Q54MC
Proteasomes function to:
A. Assemble ribosomal subunits for protein synthesis
B. Package hormones into secretory vesicles for export
C. Remove and recycle damaged, denatured, or abnormal intracellular proteins
D. Break down fatty acids and neutralize hydrogen peroxide
Correct — Proteasomes are hollow cylinders of proteolytic enzymes that break down and recycle damaged or abnormal proteins within the cytoplasm, including proteins produced in virus-infected cells.
Incorrect — The correct answer is C. Proteasomes recycle damaged/abnormal proteins. Option D describes peroxisomes. Option A describes nucleoli. Option B describes the Golgi apparatus.
Q55MC
The rough endoplasmic reticulum (RER) appears "rough" because:
A. It has numerous folds (cristae) on its inner surface
B. Fixed ribosomes are attached to its outer surface, giving it a beaded appearance
C. It is surrounded by a double membrane with irregular contours
D. It contains crystallized enzyme complexes visible under the microscope
Correct — The RER has fixed ribosomes attached to its outer surface, producing a beaded or rough appearance under electron microscopy. The smooth ER lacks ribosomes and appears smooth.
Incorrect — The correct answer is B. Rough = ribosomes on the surface. Cristae (option A) are the folds of the INNER mitochondrial membrane — a completely different organelle.
Q56SATA
Select ALL functions performed by the smooth endoplasmic reticulum (SER).
Correct — The SER synthesizes lipids and carbohydrates: phospholipids/cholesterol (for membranes), steroid hormones (in reproductive cells), and glycogen (in muscle/liver). Protein synthesis using ribosomes is a function of the ROUGH ER, not the smooth ER.
Incorrect — SER functions: lipid synthesis (phospholipids, cholesterol, steroid hormones), carbohydrate synthesis/storage (glycogen), and detoxification. Protein synthesis via ribosomes belongs to the ROUGH ER.
Q57MC
The Golgi apparatus is structurally composed of:
A. A double membrane with inner folds called cristae enclosing a fluid matrix
B. A network of membranous channels extending throughout the cytoplasm
C. A set of 5–6 flattened membranous discs called cisternae, resembling a stack of dinner plates
D. Hollow cylinders of proteolytic enzymes with regulatory proteins at the ends
Correct — The Golgi apparatus is a set of 5–6 flattened membranous discs called cisternae. Option A describes mitochondria. Option B describes the endoplasmic reticulum. Option D describes proteasomes.
Incorrect — The correct answer is C. Golgi = stacked cisternae (like dinner plates). Mitochondria have cristae (option A). ER is a network (option B). Proteasomes are hollow cylinders (option D).
Q58MC
Autolysis — the self-digestion of a cell — occurs when:
A. Mitochondria cease aerobic metabolism in the absence of oxygen
B. Lysosome membranes disintegrate in damaged or dead cells, releasing digestive enzymes into the cytosol
C. Proteasomes break down all available structural proteins
D. The Golgi apparatus stops packaging secretory vesicles
Correct — Autolysis occurs when lysosomal membranes disintegrate in damaged or dead cells, releasing their digestive enzymes into the cytosol. The enzymes rapidly destroy the cell's proteins and organelles. This is why lysosomes are called cellular "suicide packets."
Incorrect — The correct answer is B. Autolysis results from lysosomal membrane breakdown releasing active digestive enzymes into the cytosol. This is why lysosomes are called cellular "suicide packets."
Q59MC
Peroxisomes differ from lysosomes in that peroxisomes:
A. Are produced at the Golgi apparatus and digest pathogens engulfed by phagocytosis
B. Arise from growth of existing peroxisomes, catabolize fatty acids, and neutralize hydrogen peroxide
C. Contain the same enzymes as lysosomes and perform identical functions
D. Are found only in liver cells and are absent from all other body cells
Correct — Peroxisomes arise from growth and division of existing peroxisomes (not from the Golgi), break down fatty acids and organic compounds, and neutralize the hydrogen peroxide (H₂O₂) that is generated in the process. They are most abundant in metabolically active cells like liver cells but are found in all cells.
Incorrect — The correct answer is B. Key peroxisome facts: arise from existing peroxisomes (not Golgi), catabolize fatty acids, neutralize H₂O₂. Lysosomes arise from the Golgi and digest pathogens/debris.
Q60MC
The cristae of mitochondria are:
A. Small vesicles that bud off to deliver lipids to the plasma membrane
B. Folds of the inner mitochondrial membrane that increase surface area for metabolic enzyme activity
C. Pores in the outer membrane that control gas exchange
D. The fluid contents of the mitochondrial matrix
Correct — Cristae are folds of the inner mitochondrial membrane. By increasing surface area, they expose more metabolic enzymes in the matrix to substrates, maximizing ATP-producing reactions. The outer membrane surrounds the entire organelle.
Incorrect — The correct answer is B. Cristae = inner membrane folds = increased surface area for enzymes. The matrix is the fluid inside the cristae. The outer membrane surrounds the whole organelle.
Q61SATA
Select ALL organelles that are MEMBRANOUS (enclosed by a lipid membrane).
Correct — Mitochondria, Golgi apparatus, and lysosomes are membranous organelles (also: nucleus, endoplasmic reticulum, peroxisomes). Centrioles are nonmembranous — they are in direct contact with the cytosol.
Incorrect — Membranous: nucleus, mitochondria, ER, Golgi, lysosomes, peroxisomes. Nonmembranous: cytoskeleton, microvilli, centrioles, cilia, flagella, ribosomes, proteasomes. Centrioles are nonmembranous.
Q62FITB
The intracellular fluid that fills the cytoplasm around the organelles is called the ___.
Correct — The cytosol is the intracellular fluid. It contains dissolved nutrients, ions, proteins (many are enzymes), and waste products. It is part of the cytoplasm but is distinct from the organelles suspended within it.
Incorrect — The correct answer is cytosol. Cytoplasm is the general term for everything inside the plasma membrane. Cytosol is specifically the fluid component. Do not confuse these two terms.
Q63MC
In muscle cells, which cytoskeletal protein interacts with thick filaments (myosin) to generate powerful contractions?
A. Tubulin (component of microtubules)
B. Keratin (component of intermediate filaments)
C. Actin (component of microfilaments)
D. Histone (protein that wraps DNA)
Correct — Actin microfilaments interact with thick myosin filaments in muscle cells to produce contractions. This actin-myosin interaction is the molecular basis of muscle contraction.
Incorrect — The correct answer is C. Actin (microfilaments) + myosin (thick filaments) = muscle contraction. Tubulin forms microtubules. Keratin is an intermediate filament in skin. Histones wrap DNA.
2586 — Functions of the Cell Nucleus
8 questions covering nuclear structure, chromosomes, and the genetic code
Q64MC
The nucleus primarily functions as:
A. The main site of lipid and steroid hormone synthesis
B. The organelle that packages secretory vesicles and lysosomes
C. The control center for cellular operations — storing information and directing protein synthesis
D. The site where aerobic metabolism produces 95% of the cell's ATP
Correct — The nucleus is the control center. It stores all information needed to synthesize over 100,000 different proteins, determines cell structure and function, and controls which proteins are made, under what circumstances, and in what amounts.
Incorrect — The correct answer is C. The nucleus = control center. ATP production is done by mitochondria. Lipid/hormone synthesis is SER. Vesicle packaging is the Golgi apparatus.
Q65MC
Nuclear pores in the nuclear envelope:
A. Allow all substances to pass freely between nucleus and cytosol
B. Prevent all RNA from leaving the nucleus
C. Permit movement of ions and small molecules while regulating transport of proteins and RNA
D. Serve as the primary site of ribosome assembly
Correct — Nuclear pores are large enough to permit ions and small molecules to cross, but they regulate larger molecules. They allow mRNA to exit the nucleus and proteins (such as transcription factors) to enter — essential for the nucleus to communicate with the cytosol.
Incorrect — The correct answer is C. Nuclear pores permit small molecules freely but regulate larger molecules. They are the route by which mRNA exits the nucleus after transcription. The nucleolus is where ribosomal subunits are assembled.
Q66MC
Nucleoli within the nucleus primarily function to:
A. Store chromosomes in a condensed form during interphase
B. Control cell division by generating spindle fibers
C. Synthesize ribosomal RNA (rRNA) and assemble ribosomal subunits
D. Package secretory proteins into transport vesicles
Correct — Nucleoli produce ribosomal RNA and assemble it with proteins into ribosomal subunits. Nucleoli are most prominent in cells that manufacture large amounts of proteins, such as muscle and liver cells, because those cells need abundant ribosomes.
Incorrect — The correct answer is C. Nucleoli = site of rRNA synthesis and ribosomal subunit assembly. Spindle fibers come from centrioles. Transport vesicles are packaged by the Golgi apparatus.
Q67FITB
The fluid contents inside the nucleus, separated from the cytosol by the nuclear envelope, are called the ___.
Correct — Nucleoplasm is the fluid inside the nucleus. It contains ions, enzymes, RNA and DNA nucleotides, proteins, small amounts of RNA, and DNA. Compare to cytosol, which is the fluid of the cytoplasm outside the nucleus.
Incorrect — The correct answer is nucleoplasm. Nucleus fluid = nucleoplasm. Cell fluid = cytosol. Both are intracellular fluids but in different compartments.
Q68MC
In non-dividing cells, DNA exists as loosely coiled filaments called chromatin. DNA becomes visible as distinct chromosomes when:
A. Transcription is actively occurring
B. The cell is in G₁ phase performing normal metabolic functions
C. The cell is preparing for or undergoing active cell division
D. The nucleus is synthesizing large quantities of ribosomal RNA
Correct — During active cell division, DNA coils very tightly and chromosomes become visible as distinct structures under light or electron microscopy. In non-dividing cells, DNA is loosely coiled as chromatin — genes are accessible for transcription.
Incorrect — The correct answer is C. DNA condenses into visible chromosomes during cell division. During interphase (normal cell functions), DNA is loosely coiled as chromatin and cannot be seen as distinct structures.
Q69SATA
Select ALL statements about the nucleus that are correct according to the textbook.
Correct — Most cells: one nucleus. Red blood cells: none (mature RBCs also have no mitochondria or centrioles). Skeletal muscle cells: many nuclei. Neurons: typical neurons have ONE nucleus — they do not have multiple. High metabolic activity in neurons is supported by mitochondria, not extra nuclei.
Incorrect — Single nucleus = most cells; No nucleus = mature red blood cells; Multiple nuclei = skeletal muscle cells. Neurons have a SINGLE nucleus — the statement about multiple neuronal nuclei is false.
Q70MC
Histone proteins in the nucleus function to:
A. Form the nuclear pores that regulate transport of molecules
B. Synthesize ribosomal RNA within the nucleolus
C. Wrap DNA strands and help keep genes inactive until needed
D. Form the double membrane of the nuclear envelope
Correct — DNA strands wrap around histones to form nucleosomes. Histones normally keep genes inactive (tightly coiled, bound histones prevent transcription). Before a gene is expressed, enzymes must break histone bonds to expose the promoter.
Incorrect — The correct answer is C. Histones wrap DNA and keep genes inactive. DNA + histones = nucleosomes. Genes are activated when histone bonds are broken to expose the DNA promoter region.
Q71MC
The genetic code is described as a "triplet code" because:
A. Three types of RNA are involved in protein synthesis
B. A sequence of three nitrogenous bases specifies the identity of a single amino acid
C. Each gene consists of exactly three exons
D. Three separate DNA molecules combine to form a single chromosome
Correct — The genetic code is a triplet code: each group of three consecutive nitrogenous bases (a triplet on DNA, or a codon on mRNA) specifies one amino acid. For example, DNA triplet ACA codes for the amino acid cysteine.
Incorrect — The correct answer is B. Triplet code = 3 bases specify 1 amino acid. While there are indeed 3 types of RNA involved, that is not why the code is called "triplet." The triplet refers to the base-grouping system for encoding amino acids.
2587 — Protein Synthesis
11 questions covering transcription and translation
Q72MC
Transcription (the production of mRNA from a DNA template) occurs in the:
A. Cytoplasm at free ribosomes
B. Rough endoplasmic reticulum
C. Nucleus
D. Golgi apparatus
Correct — Transcription occurs in the NUCLEUS where the DNA template resides. The resulting mRNA exits through nuclear pores into the cytoplasm, where translation occurs at ribosomes.
Incorrect — The correct answer is C. Transcription (DNA→mRNA) occurs in the NUCLEUS. Translation (mRNA→protein) occurs in the CYTOPLASM. Never confuse these locations.
Q73MC
During transcription, RNA polymerase inserts which nitrogenous base into the growing mRNA strand wherever adenine (A) appears in the DNA template?
A. Thymine (T)
B. Adenine (A)
C. Guanine (G)
D. Uracil (U)
Correct — RNA uses uracil (U) instead of thymine (T). When DNA has A, mRNA gets U. All other base-pairing is standard: G↔C. This is a critical distinction between DNA and RNA.
Incorrect — The correct answer is D. RNA uses URACIL (U) in place of thymine. DNA: A-T, G-C. RNA: A-U, G-C. RNA polymerase adds U wherever the DNA template shows A.
Q74MC
Introns are removed from pre-mRNA before it leaves the nucleus because:
A. Introns are the coding sequences that specify the protein's amino acid sequence
B. Introns are non-coding sequences that do not contribute to the final protein; only exons (the coding sequences) are retained
C. Introns would block the nuclear pores and prevent mRNA from exiting
D. Introns contain the start and stop codon sequences for translation
Correct — Introns are non-coding sequences that are spliced out of pre-mRNA. Exons (the EXpressed sequences) are retained and spliced together to form the final functional mRNA. By removing different introns, a single gene can produce mRNAs that code for several different proteins.
Incorrect — The correct answer is B. Introns = non-coding, removed. Exons = coding, retained and expressed. Memory tip: Introns = INTRuding sequences; Exons = EXpressed sequences.
Q75MC
Translation always begins at which specific mRNA codon?
A. UAA — one of the three stop codons
B. AUG — the start codon, which codes for the amino acid methionine
C. GGG — the codon for the amino acid proline
D. UUU — the codon for the amino acid phenylalanine
Correct — Translation always begins at the start codon AUG, which codes for methionine. The first tRNA carrying methionine binds to AUG on the mRNA. Note: this initial methionine is removed from the finished protein.
Incorrect — The correct answer is B. AUG = start codon = methionine. Translation always begins here. UAA is a stop codon. The start codon AUG is a high-yield exam fact.
Q76MC
During translation, transfer RNA (tRNA) molecules function to:
A. Carry the genetic blueprint from the nucleus to the cytoplasm
B. Assemble the two ribosomal subunits around the mRNA strand
C. Deliver specific amino acids to the ribosome, matching their anticodon to the mRNA codon
D. Synthesize ATP to power the peptide bond formation process
Correct — tRNA molecules deliver amino acids to the ribosome. Each tRNA has an anticodon that is complementary to a specific mRNA codon. When the anticodon matches the codon, the amino acid is added to the growing polypeptide chain.
Incorrect — The correct answer is C. tRNA = amino acid delivery to ribosome. mRNA carries the blueprint from nucleus to cytoplasm (option A). Ribosomal RNA and ribosome structure assembles the subunits (option B).
Q77SATA
Select ALL statements about transcription that are correct.
Correct — Transcription: occurs in the nucleus, uses RNA polymerase, produces mRNA complementary to DNA. It does NOT directly assemble amino acids — that is translation.
Incorrect — Transcription makes mRNA (not protein). The three correct statements describe what transcription actually does: location (nucleus), enzyme (RNA polymerase), and product (complementary mRNA). Direct amino acid assembly is translation.
Q78MC
A "codon" is defined as:
A. A triplet of nitrogenous bases on tRNA that matches to mRNA
B. A sequence of three nitrogenous bases on mRNA that specifies a single amino acid
C. The DNA triplet from which an mRNA codon is transcribed
D. The promoter sequence that initiates transcription
Correct — A codon is a triplet of bases on mRNA. The sequence of codons along mRNA determines the sequence of amino acids in the protein. Option A describes the anticodon (on tRNA). Option C describes the DNA triplet.
Incorrect — The correct answer is B. Codon = triplet on mRNA. Anticodon = triplet on tRNA. DNA triplet = the template from which the codon is transcribed. Know all three terms and where each is located.
Q79MC
The anticodon on tRNA:
A. Has the same base sequence as the corresponding mRNA codon
B. Binds directly to the DNA template in the nucleus
C. Is complementary to a specific codon on mRNA and binds to it during translation
D. Codes for the amino acid to be added to the polypeptide chain
Correct — The anticodon on tRNA is complementary to (not the same as) the mRNA codon. This complementary base-pairing brings the specific amino acid carried by that tRNA into position for peptide bond formation.
Incorrect — The correct answer is C. Anticodon = complementary to the mRNA codon. Not the same sequence — complementary. The codon specifies which amino acid; the anticodon is how the correct tRNA finds the right codon.
Q80FITB
The enzyme that synthesizes mRNA by reading the DNA template during transcription is called ___ ___.
Correct — RNA polymerase binds to the promoter of a gene and moves along the DNA template, attaching complementary RNA nucleotides to form the mRNA strand. It stops at the stop signal at the end of the gene.
Incorrect — The correct answer is RNA polymerase. It binds to the gene's promoter and builds the mRNA strand. Compare to DNA polymerase, which copies DNA during replication.
Q81MC
Approximately how long does it take a ribosome to produce a typical protein of about 1,000 amino acids?
A. 2 minutes
B. 20 seconds
C. 5 minutes
D. 1 hour
Correct — Translation proceeds swiftly, producing a typical protein of about 1,000 amino acids in approximately 20 seconds. This speed reflects the efficiency of the ribosome machinery.
Incorrect — The correct answer is B. Translation is rapid — a 1,000 amino acid protein is made in approximately 20 seconds.
Q82MC
By definition, a protein is a polypeptide that contains:
A. Fewer than 50 amino acids
B. Exactly 100 amino acids in a specific sequence
C. 100 or more amino acids
D. At least 1,000 amino acids
Correct — By definition from the textbook, a protein is a polypeptide containing 100 or more amino acids. Shorter chains are simply called polypeptides or peptides depending on length.
Incorrect — The correct answer is C. A protein = 100 or more amino acids. This is the textbook definition. A typical protein used as an example is about 1,000 amino acids.
2588 — The Process of Mitosis
11 questions covering the cell life cycle, mitosis stages, and cytokinesis
Q83MC
During the S phase of interphase, the primary cellular event is:
A. Normal cell functions plus growth and organelle duplication
B. DNA replication — the complete copying of all genetic information
C. Chromosome condensation in preparation for separation
D. Cytoplasmic division to produce two daughter cells
Correct — The S phase (S = synthesis) is dedicated to DNA replication. All genetic information in the nucleus is copied during this phase, which takes 6–8 hours. G₁ is for growth; G₂ is for final protein synthesis; cytokinesis is cytoplasmic division.
Incorrect — The correct answer is B. S phase = DNA replication (S = synthesis). G₁ = growth and organelle duplication. G₂ = protein synthesis and centriole completion. Cytokinesis is cytoplasmic division that happens after mitosis.
Q84MC
Which event specifically marks the BEGINNING of prophase in mitosis?
A. Chromosomes align along the metaphase plate
B. Centromeres split and daughter chromosomes are pulled to opposite poles
C. DNA coils so tightly that chromosomes become visible under a light microscope
D. Nuclear membranes reform and nuclei return to interphase appearance
Correct — Prophase begins when DNA coils so tightly that chromosomes become visible under a microscope. As a result of prior DNA replication, each visible chromosome consists of two chromatids joined at the centromere.
Incorrect — The correct answer is C. Prophase begins with chromosome condensation and visibility. Option A = metaphase. Option B = anaphase. Option D = telophase. Remember PMAT.
Q85MC
During metaphase of mitosis, chromosomes:
A. Condense from chromatin and first become visible
B. Migrate to and align along the central metaphase plate
C. Split at the centromere and are pulled toward opposite poles
D. Uncoil back into chromatin as nuclear membranes reform
Correct — Metaphase (meta- = after) follows prophase and is characterized by chromosome alignment at the metaphase plate — the narrow central zone of the cell. Each chromosome still consists of two chromatids at this stage.
Incorrect — The correct answer is B. Metaphase = chromosomes line up at the plate. Option A = prophase. Option C = anaphase. Option D = telophase. PMAT.
Q86MC
Anaphase of mitosis begins when:
A. Spindle fibers first begin forming between centriole pairs
B. The nuclear envelope breaks down
C. All chromosomes have aligned at the metaphase plate
D. The centromere of each chromatid pair splits and the resulting daughter chromosomes are pulled to opposite poles
Correct — Anaphase (ana- = apart) begins specifically when centromeres split, separating the two chromatids into individual daughter chromosomes. Spindle fibers then pull these daughter chromosomes to opposite ends of the cell.
Incorrect — The correct answer is D. Anaphase begins with centromere splitting — chromosomes pulled APART (ana = apart). Spindle fiber formation = prophase. Nuclear envelope breakdown = late prophase. Metaphase plate alignment = end of metaphase.
Q87MC
During telophase of mitosis, the cell:
A. Condenses chromosomes for the first time and loses the nuclear envelope
B. Aligns chromosomes in the central plane of the cell
C. Splits centromeres and pulls daughter chromosomes to opposite poles
D. Reforms nuclear membranes, enlarges the nuclei, and chromosomes uncoil back to chromatin
Correct — Telophase (telos = end) is the final mitotic stage. Nuclear membranes reform around each set of daughter chromosomes, the nuclei enlarge, DNA uncoils back into chromatin, and nucleoli reappear. Each nucleus looks like an interphase nucleus again.
Incorrect — The correct answer is D. Telophase = end stage, nuclear envelope reforms, DNA uncoils. Option A = prophase. Option B = metaphase. Option C = anaphase. PMAT.
Q88FITB
The process of cytoplasmic division that forms two distinct daughter cells following mitosis is called ___.
Correct — Cytokinesis (cyto- = cell, kinesis = motion) is the division of the cytoplasm that produces two distinct daughter cells. It begins during late anaphase with a cleavage furrow and is usually completed after nuclear membranes have reformed in telophase.
Incorrect — The correct answer is cytokinesis. Mitosis = nuclear division only. Cytokinesis = cytoplasmic division. Both are required to produce two complete daughter cells.
Q89MC
Apoptosis is defined as:
A. The uncontrolled cell division characteristic of malignant tumors
B. The genetically controlled death of cells — activation of "suicide genes"
C. The migration of cancer cells to distant tissues to form secondary tumors
D. The process by which cells become specialized through gene silencing
Correct — Apoptosis (apo- = separated from, ptosis = a falling) is genetically controlled cell death. It is a key homeostatic process. For example, immune cells activate apoptosis genes in abnormal or infected cells, causing them to self-destruct.
Incorrect — The correct answer is B. Apoptosis = programmed cell death (suicide genes). Not uncontrolled division (that is cancer). Not metastasis. Not differentiation. Apoptosis is a normal, controlled, homeostatic process.
Q90SATA
Select ALL events that correctly describe what occurs during PROPHASE of mitosis.
Correct — During prophase: chromosomes condense and become visible, nucleoli disappear, centrioles migrate to opposite poles forming spindle fibers, and the nuclear envelope breaks down late in prophase. Chromosome alignment at the plate = METAPHASE, not prophase.
Incorrect — Prophase events: chromosome condensation and visibility, nucleoli disappear, centrioles migrate to poles, spindle fibers form, nuclear envelope breaks down. Chromosome alignment at the metaphase plate is METAPHASE — the next stage.
Q91MC
The primary purpose of the G₁ phase of interphase is:
A. DNA replication — copying all genetic material
B. Completion of centriole replication and final protein synthesis before division
C. Normal cell functions plus cell growth, organelle duplication, and protein synthesis
D. Cytoplasmic division into two daughter cells
Correct — G₁ is the first phase after cell division. The cell performs its normal functions, grows, duplicates organelles, and synthesizes proteins. Duration varies widely — 8 hours in fast-dividing cells, days to weeks in others. DNA replication occurs in S phase.
Incorrect — The correct answer is C. G₁ = growth and normal function. S = DNA replication. G₂ = final protein synthesis and centriole completion. Cytokinesis = cytoplasmic division after mitosis.
Q92MC
The spindle fibers that separate chromosomes during mitosis are composed of:
A. Actin microfilaments
B. Intermediate filaments of keratin
C. Microtubules
D. DNA strands
Correct — Spindle fibers are composed of microtubules extending from centrioles. During cell division, microtubules form the spindle apparatus that distributes duplicated chromosomes to opposite ends of the dividing cell.
Incorrect — The correct answer is C. Spindle fibers = microtubules, produced by centrioles. Actin microfilaments = muscle contraction and membrane support. Intermediate filaments = structural support. DNA forms chromosomes, not spindle fibers.
Q93MC
A cleavage furrow forms during:
A. Prophase, when chromosomes first begin to condense
B. Metaphase, when chromosomes align at the central plate
C. Late anaphase through telophase, marking the beginning of cytokinesis
D. The S phase of interphase, when DNA is replicated
Correct — The cleavage furrow — a constriction of the cytoplasm along the plane of the former metaphase plate — begins forming in late anaphase and deepens through telophase. Its completion marks the end of cytokinesis and cell division.
Incorrect — The correct answer is C. The cleavage furrow forms during late anaphase/telophase as part of cytokinesis. It is the physical constriction that pinches the cell into two daughter cells.
2589 — Differentiation, Tumors, and Cancer
7 questions covering cell specialization and abnormal cell growth
Q94MC
Cellular differentiation — the process by which cells become specialized — occurs because:
A. Different cell types in the body acquire different DNA sequences over time
B. Different sets of genes are selectively activated or silenced in different cell types
C. Specialized cells contain fewer chromosomes than stem cells
D. RNA polymerase functions differently in each organ based on local pH
Correct — All somatic cells have the SAME DNA. Differentiation occurs because different genes are turned off in different cell types. A liver cell and a fat cell have identical chromosomes; they differ because a different set of genes has been silenced in each.
Incorrect — The correct answer is B. Differentiation is caused by selective gene activation or silencing — NOT by differences in DNA sequence. All body cells have identical genetic material. Different cells express different subsets of genes.
Q95FITB
A mass or swelling produced by abnormal cell growth and division is called a ___ (or neoplasm).
Correct — A tumor (neoplasm) forms when the rate of cell division and growth exceeds the rate of cell death. Tumors may be benign (localized, rarely life-threatening) or malignant (invasive, potentially fatal).
Incorrect — The correct answer is tumor (or neoplasm). When growth exceeds death, tissue enlarges abnormally. Tumors are classified as benign or malignant based on their behavior.
Q96MC
A benign tumor differs from a malignant tumor in that a benign tumor:
A. Can metastasize and form secondary tumors at distant organ sites
B. Invades surrounding connective tissue and organs
C. Remains localized within the epithelium or a connective tissue capsule and is rarely life-threatening
D. No longer responds to normal cell growth control mechanisms
Correct — Benign tumors remain localized. They do not invade surrounding tissue or metastasize. They can usually be surgically removed if their size or position disturbs function. Options A, B, and D all describe malignant tumors.
Incorrect — The correct answer is C. Benign = stays localized in a capsule, rarely fatal. Malignant = invades tissue, can metastasize, ignores normal growth controls. The key distinction is localization vs invasion/spread.
Q97MC
Metastasis refers to:
A. The local spread of malignant cells directly into immediately surrounding tissue
B. The genetically programmed death of abnormal cells
C. The migration of cancer cells through blood or lymph to distant tissues and organs where they establish secondary tumors
D. The initial development of a mutation that causes a cell to become cancerous
Correct — Metastasis is the migration of cancer cells to DISTANT tissues to form secondary tumors. Option A describes invasion (local spread). Metastasis is what makes cancer so difficult to treat — secondary tumors can form throughout the body.
Incorrect — The correct answer is C. Metastasis = distant spread. Invasion = local spread into adjacent tissue. These are distinct processes. The primary tumor is the original site; secondary tumors result from metastasis.
Q98SATA
Select ALL statements that correctly describe cancer cells and malignant tumor behavior.
Correct — Cancer cells ignore growth controls, stimulate angiogenesis (new blood vessel formation to feed themselves), and compete with normal tissue for resources. They do NOT remain contained — that describes benign tumors. Containment in a capsule is a feature of benign tumors.
Incorrect — Cancer cells: ignore growth controls, stimulate new blood vessel growth, compete for nutrients with normal cells. The statement about remaining in a capsule describes BENIGN tumors — cancer cells invade and spread.
Q99MC
Cancer most often begins in areas of rapid cell division because:
A. Rapidly dividing cells produce less DNA repair enzyme
B. Fast-dividing cells have weaker plasma membranes that allow carcinogens to enter
C. The more times chromosomes are copied, the greater the chance of a copying error (mutation)
D. Rapidly dividing cells contain more peroxisomes that generate damaging hydrogen peroxide
Correct — Cancer results from mutations. The more times DNA is copied, the higher the probability of an error in the copying process. Areas of rapid division (like skin, intestinal lining, bone marrow) are therefore at higher cancer risk.
Incorrect — The correct answer is C. More copying = more chances for error. Cancer starts with mutations, and mutations occur most often during DNA replication. High turnover tissues have the highest mutation risk.
Q100MC
The term "primary tumor" refers to:
A. The most dangerous secondary tumor at a distant organ site
B. A tumor that grows most rapidly among multiple concurrent tumors
C. The original site where cancer cells first developed
D. A benign tumor with the highest potential to become malignant
Correct — The primary tumor (primary neoplasm) is the original site where cancer first developed. It is the source from which cells may later metastasize to form secondary tumors at distant locations.
Incorrect — The correct answer is C. Primary tumor = original site of cancer development. Secondary tumors = colonies resulting from metastasis. Knowing the primary site guides diagnosis and treatment decisions.
SOMAPL13 — Exam Complete
Cell Structure and Function — 100 Questions
— correct
— incorrect
100 total
SOMAPL13 — Cell Structure and Function
Objectives 2581–2589 · Chapter 3 · 15 Exam Questions · Password is SOMAPL13
Incorrect password.
2581 — VocabularyAdvanced
10 questions — College-level, based on Martini Essentials of Anatomy & Physiology
Q1
MC
The word "cytology" is derived from the Greek root "kytos." Based on its use in biology, which definition BEST matches this root?
Tissue
Cell
Nucleus
Organism
Q2
MC
The root "phago" appears in the term phagocytosis. Which activity does this root describe?
To drink
To eat
To divide
To push
Q3
FITB
Complete the following: The prefix "hypo-" means below or deficient. A solution described as ___ has a lower solute concentration than the fluid inside a cell.
Q4
MC
The suffix "-lysis" appears in hemolysis and hydrolysis. Based on these examples, "-lysis" means:
Formation or creation
Transport across a membrane
A loosening, dissolving, or breaking apart
Synthesis or building up
Q5
MC
The term "osmosis" derives from the Greek word "osmos." Based on how osmosis functions, the root "osmos" most likely means:
To dissolve
To thrust or push
To separate
To equalize
Q6
SATA
Select ALL terms that use the prefix "endo-" (meaning inside or within) correctly.
Q7
MC
The term "mitosis" derives from the Greek "mitos," meaning thread. This name was chosen because:
The process involves threading DNA through nuclear pores
Chromosomes appear as thread-like structures when they condense and become visible under a microscope
The spindle fibers look like threads sewn through the cytoplasm
The chromatin forms a threadlike network to guide cytokinesis
Q8
MC
A cell biologist states that a particular structure performs "phagocytosis." Breaking apart the word: phago = to eat, cyto = cell, -osis = process. Phagocytosis literally means:
The process of a cell producing food through photosynthesis
The process of a cell dissolving its own organelles
The process of a cell eating — engulfing solid particles
The process of a cell dividing to produce daughter cells
Q9
FITB
The word "apoptosis" comes from the Greek roots "apo" (separated from) and "ptosis" (a falling). Apoptosis literally means a ___ away — and describes genetically programmed cell death.
Q10
MC
Which of the following correctly pairs a word root with its meaning AND an example term from Chapter 3?
soma = body; ribosome — a ribonucleic acid body
mitos = granule; mitochondrion — a granule that generates heat
reticulum = thread; endoplasmic reticulum — a thread network inside the cell
kinesis = color; cytokinesis — the coloring of cytoplasm during division
2582 — Cell TheoryAdvanced
7 questions — College-level, based on Martini Essentials of Anatomy & Physiology
Q11
MC
Which statement is a main point of the cell theory as presented in Essentials of Anatomy & Physiology?
All cells contain a nucleus that stores the genetic information of the organism
Cells are the building blocks of all plants and animals
The number of cells in an organism is determined at fertilization and does not change
Only eukaryotic cells can maintain homeostasis
Q12
SATA
Select ALL four main points of the cell theory as stated in the Martini textbook.
Q13
MC
According to the cell theory, new cells in the body arise from:
Spontaneous organization of organic molecules in the extracellular fluid
Division of preexisting cells
Differentiation of stem cells that form de novo from nutrients
Fusion of individual organelles that coalesce into a new cell
Q14
MC
The Martini textbook states that each cell "maintains homeostasis at the cellular level." This means each cell:
Can adjust the homeostasis of the entire organism without central coordination
Monitors and adjusts its own internal environment to remain within functional limits
Produces hormones that signal other cells to maintain systemic homeostasis
Undergoes apoptosis whenever the extracellular environment changes
Q15
MC
Cytology is defined in the Martini textbook as:
The study of tissues and the four major tissue types
The study of organ systems and how they interact
The study of the structure and function of cells
The study of heredity and genetic information in cells
Q16
MC
A scientist discovers that isolated mitochondria removed from a cell can perform aerobic respiration independently for a short time in the correct solution.
Does this observation contradict cell theory?
Yes — it proves organelles are the smallest functioning units of life, not cells
No — organelles can perform isolated reactions but cannot independently maintain homeostasis, reproduce, or sustain life
Yes — it shows that cells are not required for aerobic metabolism
No — the observation proves cell theory is wrong and must be revised
Q17
FITB
The cell theory states that cells are the smallest ___ units of life — meaning the smallest level at which all life processes can occur simultaneously.
2583 — Plasma MembraneAdvanced
12 questions — College-level, based on Martini Essentials of Anatomy & Physiology
Q18
MC
The Martini textbook lists four general functions of the plasma membrane. Which of the following is NOT one of these four functions?
Physical isolation of the cell's contents from the extracellular environment
Regulation of exchange between the cell and its environment
Synthesis of ATP to power cellular activities
Structural support through connections to other cells and extracellular materials
Q19
MC
The plasma membrane is described as "selectively permeable." This means:
The membrane allows all substances to pass freely in both directions
The membrane blocks all substances from entering or leaving the cell
The membrane permits some materials to pass while restricting or blocking others
The membrane is permeable only during active cell division
Q20
MC
In the phospholipid bilayer, the hydrophobic fatty acid tails are oriented:
Outward, facing the extracellular fluid on both sides
Inward, facing each other and away from the aqueous environments on either side
Randomly distributed throughout the membrane without a consistent orientation
Attached to membrane proteins that anchor them to the cytoskeleton
Q21
MC
Cholesterol molecules are interspersed throughout the plasma membrane. Their primary function at normal body temperature is to:
Provide attachment sites for peripheral membrane proteins
Increase the rigidity of the membrane to prevent excessive fluidity
Serve as the primary barrier to water movement across the membrane
Act as receptor proteins for steroid hormones
Q22
SATA
The Martini textbook identifies six functional classes of membrane proteins. Select ALL that are included in this classification.
Q23
MC
Glycoproteins and glycolipids on the outer surface of the plasma membrane serve primarily as:
Ion channels that regulate sodium and potassium movement
Anchors that attach the membrane to the internal cytoskeleton
Cell lubricants, adhesives, extracellular receptors, and identity markers for immune recognition
Enzymes that break down nutrients in the extracellular fluid
Q24
FITB
Channel proteins that are specifically dedicated to water transport across the plasma membrane are called ___.
Q25
MC
A substance that is small, nonpolar, and lipid-soluble would cross the plasma membrane by which mechanism?
Facilitated diffusion through carrier proteins
Active transport using the sodium-potassium pump
Direct diffusion through the phospholipid bilayer without protein assistance
Receptor-mediated endocytosis after binding to a surface receptor
Q26
MC
Which type of membrane protein would be most important for a cell to receive and respond to the hormone insulin?
Anchoring proteins — to hold the cell in place while responding
Carrier proteins — to transport insulin across the membrane into the cytoplasm
Receptor proteins — to bind insulin and trigger an intracellular response
Recognition proteins — to identify insulin as a self molecule
Q27
SATA
Select ALL substances that can cross the plasma membrane directly through the phospholipid bilayer WITHOUT requiring a membrane protein.
Q28
MC
The Martini textbook describes the plasma membrane as providing "structural support." In this context, structural support refers to:
The stiffness of the phospholipid bilayer preventing membrane deformation
Specialized connections between plasma membranes, or between membranes and extracellular materials, that give tissues stability
The role of intermediate filaments in keeping the nucleus anchored at the cell center
Membrane proteins that synthesize collagen fibers outside the cell
Q29
MC
Which statement correctly describes the location of recognition proteins (identifiers) on the plasma membrane?
Embedded in the inner leaflet of the plasma membrane facing the cytoplasm
Located in the middle of the bilayer anchored by hydrophobic sequences
Exposed on the outer surface of the plasma membrane where they can be evaluated by other cells
Found exclusively on the membranes of lysosomes and peroxisomes
2584 — TransportAdvanced
15 questions — College-level, based on Martini Essentials of Anatomy & Physiology
Q30
MC
Diffusion is defined in the Martini textbook as the net movement of molecules from an area of higher concentration to an area of lower concentration. This movement is driven by:
ATP energy provided by mitochondria
Carrier proteins that bind and release molecules at each step
The kinetic energy of the molecules themselves
Osmotic pressure gradients generated by the sodium-potassium pump
Q31
MC
A red blood cell is placed in a solution with a lower solute concentration than the cell's cytosol. Based on the principles of osmosis, what will occur?
Water will leave the cell and the cell will shrink and crenate
The cell will remain unchanged because its membrane prevents all water movement
Water will enter the cell by osmosis and the cell may swell and eventually lyse — a process called hemolysis
Solutes will enter the cell by active transport to equalize concentrations
Q32
MC
Normal saline is a 0.9% NaCl solution used for intravenous fluid replacement. The Martini textbook explains that this concentration is used because it:
Matches the normal glucose concentration of plasma and cells
Is equivalent to the normal osmotic concentration of extracellular fluid, making it isotonic to body cells
Is the minimum NaCl concentration required to prevent hemolysis
Contains the same ion ratio as intracellular fluid (high K⁺, low Na⁺)
Q33
FITB
The process of filtration across capillary walls is driven by ___ pressure — the pressure generated by the pumping action of the heart pushing blood through vessels.
Q34
MC
Facilitated diffusion differs from simple diffusion in one critical way. Which statement correctly identifies this difference?
Facilitated diffusion moves substances against their concentration gradient; simple diffusion does not
Facilitated diffusion requires ATP energy; simple diffusion does not
Facilitated diffusion uses carrier proteins and reaches a maximum transport rate when all carriers are occupied (saturation)
Facilitated diffusion only moves water; simple diffusion moves all other molecules
Q35
SATA
The sodium-potassium (Na⁺/K⁺) exchange pump performs active transport. Select ALL statements that correctly describe this pump.
Q36
MC
The Martini textbook describes three types of endocytosis. Which of the following is NOT one of these three types?
Receptor-mediated endocytosis
Pinocytosis
Phagocytosis
Exocytosis
Q37
MC
Pinocytosis is often called "cell drinking." According to the Martini textbook, pinocytosis:
Is selective — only specific solute molecules are taken into the cell by this mechanism
Is nonselective — vesicles form that contain samples of the extracellular fluid with whatever happens to be in it
Is performed only by specialized white blood cells and macrophages
Requires receptor proteins on the membrane surface to bind the ingested fluid
Q38
MC
During receptor-mediated endocytosis, after a ligand binds to a receptor on the plasma membrane, the membrane indents and forms a coated vesicle. What happens to the receptor proteins after the vesicle fuses with a lysosome?
They are permanently destroyed by the lysosomal digestive enzymes
They are recycled back to the plasma membrane surface to be used again
They migrate to the nucleus to alter gene expression
They are exported from the cell by exocytosis along with waste products
Q39
SATA
Select ALL mechanisms that are correctly classified as PASSIVE transport (requiring no cellular energy/ATP).
Q40
MC
Phagocytosis is described in the Martini textbook as a process performed by only a few specialized cell types. The cell uses ___ to surround and engulf solid particles.
Flagella
Microvilli
Pseudopodia
Cilia
Q41
MC
In the Martini textbook, cotransport is described as a type of active transport. How does cotransport differ from primary active transport such as the Na⁺/K⁺ pump?
Cotransport uses ATP directly to move both molecules; primary active transport uses a concentration gradient
Cotransport is passive; primary active transport is active
Cotransport uses the energy stored in an ion gradient (not ATP directly) to move a second substance against its gradient
Cotransport moves two identical molecules in opposite directions; primary active transport moves one molecule
Q42
MC
A resting cell is placed in a hypertonic solution. The solution has a higher solute concentration than the cell's cytosol.
What will happen to the red blood cell over time?
Water will move into the cell by osmosis and the cell will swell
Water will move out of the cell by osmosis, the cell will shrink, and its membrane will become notched — a process called crenation
Solutes will move out of the cell by active transport to restore equilibrium
The cell will maintain normal volume because the sodium-potassium pump compensates
Q43
FITB
The process by which water and small dissolved substances are forced across a membrane by mechanical pressure — such as blood pressure forcing plasma out of capillaries into tissues — is called ___.
Q44
MC
According to the Martini textbook, exocytosis is the process in which:
The cell membrane indents to form vesicles that bring extracellular material into the cell
Vesicles formed inside the cell fuse with the plasma membrane and discharge their contents to the outside
Large solid particles are engulfed by extensions of the plasma membrane
Carrier proteins transport molecules across the membrane by changing their shape
2585 — OrganellesAdvanced
18 questions — College-level, based on Martini Essentials of Anatomy & Physiology
Q45
MC
The cytosol — the intracellular fluid of the cell — has an ionic composition that differs from extracellular fluid. According to the Martini textbook, the cytosol contains:
High Na⁺ and low K⁺, matching the extracellular fluid
High K⁺ and low Na⁺, opposite to the extracellular fluid
Equal concentrations of Na⁺ and K⁺
No dissolved ions — only dissolved proteins and nutrients
Q46
MC
Microvilli are found on the exposed surfaces of cells lining the intestines and kidney tubules. Their primary function is to:
Generate coordinated beating movements to sweep material along the surface
Anchor the cell to the basement membrane below it
Increase the surface area of the plasma membrane available for absorption
Provide the force needed to propel the cell through fluids
Q47
MC
The Martini textbook describes centrioles as having a 9+0 arrangement of microtubule triplets. Which statement correctly describes the function of centrioles?
They produce ribosomal RNA and assemble ribosomal subunits
They form the spindle apparatus during cell division and organize microtubule-based structures
They generate the ATP needed to power cell division
They serve as the structural core of microvilli in absorptive cells
Q48
SATA
The Martini textbook identifies certain cell types that lack centrioles. Select ALL cell types that cannot divide because they lack centrioles.
Q49
MC
Cilia have a 9+2 arrangement of microtubule doublets and use ATP-powered dynein to generate movement. According to the Martini textbook, cilia in the respiratory tract function to:
Propel the epithelial cells along the surface to clear debris
Move a layer of mucus and trapped particles upward toward the throat
Produce mucus that lines the respiratory tract
Provide additional surface area for gas exchange in the airways
Q50
MC
Ribosomes are described as "nonmembranous organelles." Free ribosomes are found in the cytoplasm. According to the textbook, proteins synthesized by free (unattached) ribosomes are:
Exported from the cell via secretory vesicles after Golgi processing
Inserted into the plasma membrane as integral transmembrane proteins
Used inside the cell — released into the cytosol
Transported into the nucleus to serve as histone proteins
Q51
FITB
The rough endoplasmic reticulum appears "rough" under electron microscopy because of the ___ attached to its outer surface.
Q52
MC
The smooth endoplasmic reticulum (SER) lacks ribosomes and has different functions from the rough ER. Which function is correctly attributed to the smooth ER?
Synthesis and processing of secretory proteins destined for export
Assembly of ribosomal subunits from rRNA and protein
Synthesis of lipids, steroid hormones, and glycogen; drug detoxification in liver cells
Packaging of proteins into lysosomes, secretory vesicles, and membrane segments
Q53
MC
The Golgi apparatus is described as consisting of 5–6 flattened membranous discs called cisternae. Which statement correctly describes the Golgi's role in the cell?
It is the primary site of ATP production through aerobic respiration
It synthesizes ribosomal RNA needed for ribosome construction
It processes, modifies, and packages products from the endoplasmic reticulum into three types of vesicles
It breaks down damaged organelles and recycled cellular components
Q54
MC
Lysosomes are described in the Martini textbook as containing powerful digestive enzymes. When lysosome membranes disintegrate in a damaged or dead cell, releasing these enzymes into the cytoplasm, the process is called:
Apoptosis
Autolysis
Phagocytosis
Exocytosis
Q55
SATA
Select ALL correct statements about peroxisomes according to the Martini textbook.
Q56
MC
Mitochondria produce approximately 95% of a cell's ATP through aerobic metabolism. The inner mitochondrial membrane has inward folds called cristae. The purpose of the cristae is to:
Separate the mitochondrial matrix from the cytosol of the cell
Store the glycogen that fuels the Krebs cycle reactions
Dramatically increase the surface area of the inner membrane, accommodating more ATP-producing enzyme complexes
Form the structural scaffold that holds the two mitochondrial membranes apart
Q57
MC
The cytoskeleton is a network of protein filaments that maintains cell shape, organizes organelles, and enables movement. According to the Martini textbook, which cytoskeletal element is composed of actin subunits?
Microtubules — the largest cytoskeletal element used for spindle formation and transport
Intermediate filaments — stable filaments providing tensile strength
Microfilaments — the thinnest cytoskeletal element that interacts with myosin in muscle
Centrioles — cylindrical structures organizing the spindle apparatus
Q58
SATA
According to the Martini textbook, which cell types possess flagella?
Q59
MC
Proteasomes are described in the Martini textbook as hollow cylinders of proteolytic enzymes. Their specific function is to:
Synthesize proteins from amino acids using mRNA as a template
Degrade damaged, denatured, or abnormal intracellular proteins and recycle their amino acids
Break down fatty acids in the same manner as peroxisomes
Digest material engulfed by phagocytosis
Q60
FITB
Glycolysis — the first stage of glucose catabolism — occurs in the ___, not inside the mitochondria.
Q61
MC
The Martini textbook states that the mitochondria produce approximately 95% of a cell's ATP through aerobic metabolism. The remaining approximately 5% is produced by:
The smooth endoplasmic reticulum during lipid synthesis
Glycolysis in the cytoplasm
The Golgi apparatus during vesicle formation
Ribosomes as a byproduct of translation
Q62
MC
Which statement correctly describes the structural difference between cilia (9+2 arrangement) and centrioles (9+0 arrangement)?
Both have the same arrangement of microtubule doublets — 9+2
Cilia have 9 pairs of outer microtubule doublets plus 2 central microtubules; centrioles have 9 sets of triplets and no central pair
Centrioles have 9+2 doublets and are motile; cilia have 9+0 triplets and are nonmotile
Both structures are composed of actin microfilaments rather than microtubules
2586 — NucleusAdvanced
8 questions — College-level, based on Martini Essentials of Anatomy & Physiology
Q63
MC
The Martini textbook describes the nucleus as the control center for cellular operations. Which statement correctly identifies the primary mechanism by which the nucleus controls the cell?
The nucleus directly contacts each organelle through cytoplasmic bridges
The nucleus controls the cell by determining which proteins are made, when, and in what amounts
The nucleus generates ATP signals that regulate the activity of each organelle
The nucleus stores all cellular enzymes and releases them when metabolism is needed
Q64
MC
The nuclear envelope consists of two membranes and contains nuclear pores. The outer membrane of the nuclear envelope is continuous with which structure?
The plasma membrane of the cell
The inner membrane of the mitochondria
The rough endoplasmic reticulum
The membrane of the Golgi apparatus
Q65
MC
Nuclear pores are large protein complexes embedded in the nuclear envelope. Their function is to:
Allow all substances to diffuse freely between the nucleus and cytoplasm without restriction
Block all transport between the nucleus and cytoplasm to protect DNA
Regulate transport between the nucleus and cytoplasm — allowing small molecules freely while controlling larger molecules such as proteins and RNA
Serve as anchor points for the chromosomes during cell division
Q66
MC
The nucleolus within the nucleus has a specific function described in the Martini textbook. The nucleolus:
Stores DNA in a condensed form as chromosomes during interphase
Synthesizes ribosomal RNA (rRNA) and assembles ribosomal subunits
Controls cell division by generating signals that initiate the cell cycle
Produces the spindle fibers needed to separate chromosomes during mitosis
Q67
FITB
DNA in non-dividing cells exists as loosely coiled material called ___. This loose form allows genes to be accessed for transcription.
Q68
MC
The Martini textbook describes the genetic code as a "triplet code." This means:
Three separate RNA molecules are needed for each step of protein synthesis
Three consecutive nitrogenous bases in DNA specify the identity of a single amino acid
Each gene contains exactly three exons that are expressed during protein synthesis
Three copies of each chromosome ensure accurate protein production
Q69
SATA
Select ALL correct statements about chromosomes in a typical human somatic cell.
Q70
MC
The Martini textbook defines a gene as:
Any DNA sequence that can be transcribed into RNA, whether it codes for a protein or not
The entire set of instructions needed to build a complete organism
The sequence of DNA triplets containing all the information needed to produce a specific polypeptide
A single triplet of three bases that codes for one amino acid
2587 — Protein SynthesisAdvanced
11 questions — College-level, based on Martini Essentials of Anatomy & Physiology
Q71
MC
Transcription is the first step of protein synthesis. Which statement correctly describes transcription?
Transcription occurs in the cytoplasm at ribosomes using tRNA as a template
Transcription is the process of building a polypeptide chain from amino acids
Transcription occurs in the nucleus, where RNA polymerase uses a DNA strand as a template to produce mRNA
Transcription produces tRNA molecules that carry amino acids to the ribosome
Q72
MC
During transcription, RNA polymerase builds the mRNA strand by adding complementary bases. In RNA, the base uracil (U) is used instead of thymine (T). If the DNA template strand reads 3'–ATCG–5', the resulting mRNA sequence will be:
3'–TAGC–5'
5'–UAGC–3'
5'–ATCG–3'
3'–UAGC–5'
Q73
MC
After transcription produces pre-mRNA, the pre-mRNA undergoes processing before leaving the nucleus. This processing includes removing non-coding sequences called introns. The remaining coding sequences that are expressed are called:
Anticodons
Exons
Promoters
Stop signals
Q74
FITB
During translation, transfer RNA molecules carry specific amino acids to the ribosome. The three-base sequence on the tRNA that recognizes and pairs with the mRNA codon is called the ___.
Q75
MC
Translation always begins at a specific start codon on the mRNA. According to the Martini textbook, the start codon is:
UAA, which codes for lysine
UGA, which codes for cysteine
AUG, which codes for methionine
GGG, which codes for glycine
Q76
MC
During translation, the ribosome moves along the mRNA and peptide bonds form between successive amino acids. How rapidly does a ribosome produce a typical protein of about 1000 amino acids?
Approximately 20 minutes
Approximately 1 hour
Approximately 20 seconds
Approximately 20 hours
Q77
SATA
Three types of RNA are involved in protein synthesis. Select ALL correct pairings of RNA type with its function.
Q78
MC
The Martini textbook describes a "polypeptide" as a chain of amino acids. When does a polypeptide become classified as a "protein"?
When it contains at least 10 amino acids and begins to fold
When it is released from the ribosome into the cytoplasm
When it contains 100 or more amino acids
When it undergoes glycosylation in the Golgi apparatus
Q79
MC
The Martini textbook notes that the genetic code contains redundancy — meaning multiple codons can specify the same amino acid. For example, both UUU and UUC code for phenylalanine. This redundancy is important because:
It allows cells to produce more protein from less mRNA
It means some mutations (particularly at the third codon position) may not change the amino acid, reducing the effect of certain mutations
It increases the number of different amino acids that can be incorporated into proteins
It prevents stop codons from accidentally terminating protein synthesis
Q80
MC
The Martini textbook describes a mutation called a "point mutation" where a single nucleotide change occurs in a DNA sequence. Sickle cell anemia results from a point mutation in the gene for beta-globin that causes one amino acid to change. This type of point mutation, which changes one amino acid in the final protein, is called:
A frameshift mutation
A silent (synonymous) mutation
A missense mutation
A nonsense mutation
Q81
FITB
The sequence of three mRNA bases that specifies a single amino acid during translation is called a ___.
2588 — MitosisAdvanced
11 questions — College-level, based on Martini Essentials of Anatomy & Physiology
Q82
MC
The Martini textbook describes the cell life cycle as having two main phases. Interphase and mitotic cell division. The LONGEST portion of the cell life cycle in most cells is:
Mitosis — when the chromosomes are actively being separated
Interphase — when the cell performs its normal functions and prepares for division
Cytokinesis — when the cytoplasm divides into two daughter cells
Prophase — when chromosomes first become visible under the microscope
Q83
MC
The S phase of interphase is defined by one primary event. Which of the following correctly describes what happens during S phase?
The cell grows rapidly and duplicates its organelles
All of the DNA in the nucleus is replicated by DNA polymerase
The cell synthesizes proteins needed for spindle formation
Chromosomes condense and become visible under a light microscope
Q84
MC
During prophase of mitosis, several events occur. Which of the following correctly describes a prophase event?
Chromosomes align along the cell's equatorial plate (metaphase plate)
Centromeres split and daughter chromosomes are pulled toward opposite poles
Nuclear membranes reform and the cell returns to its interphase appearance
Chromatin condenses into visible chromosomes; centrioles migrate to opposite poles and form spindle fibers; the nuclear envelope breaks down
Q85
FITB
During anaphase, the centromeres split and the two chromatids of each chromosome are pulled to opposite poles of the cell by shortening ___ fibers.
Q86
SATA
Select ALL events that correctly describe what occurs during TELOPHASE of mitosis.
Q87
MC
Cytokinesis is the division of the cytoplasm following nuclear division. According to the Martini textbook, cytokinesis in animal cells begins with:
The reformation of the nuclear envelope around each set of chromosomes
The disappearance of spindle fibers from the cell
A cleavage furrow forming along the plane of the former metaphase plate
The condensation of chromosomes at the beginning of prophase
Q88
MC
The Martini textbook describes apoptosis as "genetically programmed cell death" involving the activation of "suicide genes." Apoptosis differs from necrosis in that:
Apoptosis is a form of cellular malfunction; necrosis is a normal life cycle event
Apoptosis is an orderly, controlled process that does not damage surrounding tissue; necrosis is disorganized and triggers inflammation
Apoptosis occurs only in cancer cells; necrosis occurs only in normal cells
Apoptosis always involves lysosomal rupture; necrosis uses the caspase enzyme pathway
Q89
MC
Point mutations can affect protein function. The Martini textbook specifically discusses thalassemia as an example of a disease caused by a single nucleotide variation. Thalassemia involves an abnormality in:
Ribosome structure, preventing adequate protein synthesis
A glycolytic enzyme, reducing the cell's ability to produce ATP
Globin chains, producing abnormal or inadequate hemoglobin
Membrane channel proteins, disrupting ion balance in red blood cells
Q90
SATA
Select ALL correct statements about the G₁ phase of interphase.
Q91
MC
According to the Martini textbook, which cell types in the adult body have lost their centrioles and can no longer divide by mitosis?
Liver cells and kidney cells
Intestinal epithelial cells and skin cells
Mature red blood cells, skeletal muscle cells, cardiac muscle cells, and most neurons
Only cancer cells — normal cells always retain the ability to divide
Q92
MC
During metaphase, chromosomes align at the metaphase plate. At this point in the cell cycle, each chromosome consists of:
A single DNA molecule — the original unreplicated chromosome
Four chromatids held together at two centromeres
Two identical sister chromatids joined at a single centromere
Two chromosomes loosely associated without any physical connection
2589 — DifferentiationAdvanced
8 questions — College-level, based on Martini Essentials of Anatomy & Physiology
Q93
MC
The Martini textbook defines differentiation as the process by which cells develop specific structural and functional characteristics. Differentiation occurs because:
Different cell types receive different DNA sequences during development
Mutations accumulate in somatic cells causing them to specialize
Different genes are activated or suppressed in different cell types, even though all cells have the same DNA
Specialized cells contain fewer chromosomes than stem cells
Q94
MC
The Martini textbook explains that in differentiated cells, the genes that are NOT needed for that cell's function are:
Permanently deleted from the cell's DNA to save space
Converted to rRNA sequences to repurpose the genetic material
Silenced but still present in the genome and potentially recoverable
Transcribed into mRNA but the proteins are immediately degraded
Q95
FITB
A tumor in which the cells continue to grow and divide but remain localized within a connective tissue capsule and do not spread to other tissues is classified as a ___ tumor.
Q96
MC
The Martini textbook distinguishes between invasion and metastasis in the description of malignant tumors. Which statement correctly defines metastasis?
The local spread of tumor cells into immediately surrounding tissue
The formation of a tumor from a single cell that has undergone a cancerous mutation
The spread of cancer cells from the primary tumor through blood or lymphatic vessels to establish secondary tumors in distant tissues
The process by which cancer cells stimulate growth of new blood vessels to supply the tumor
Q97
SATA
Select ALL statements that correctly describe malignant tumors according to the Martini textbook.
Q98
MC
Cancer tends to develop most often in tissues where cells divide rapidly, such as the skin, the lining of the intestinal tract, and the bone marrow. According to the Martini textbook, the primary reason cancer is more common in these tissues is:
These tissues are more exposed to carcinogens in the external environment
Rapidly dividing cells lack the DNA repair mechanisms found in slowly dividing cells
The more frequently chromosomes are copied, the greater the likelihood of a copying error (mutation) that could disrupt cell cycle regulation
Cells in rapidly dividing tissues have fewer chromosomes and are therefore more susceptible to mutation
Q99
MC
The Martini textbook states that benign tumors can be surgically removed. However, malignant tumors can be lethal because:
Malignant tumor cells divide faster than any surgical procedure can remove them
Malignant tumors cause immediate organ failure by blocking blood flow
Malignant tumors can spread to and invade vital organs, disrupting their function, and are often impossible to completely remove
Malignant tumor cells produce toxins that are poisonous to surrounding normal cells
Q100
MC
According to the Martini textbook, which statement most completely explains why all cells in the body — despite having identical DNA — can look and function so differently?
Each cell type contains a different number of chromosomes, affecting which genes are available
Random mutations during development cause each cell type to develop a unique genetic sequence
Differentiating cells gradually lose the genes they do not need until each cell type retains only its required genes
Differentiation involves the selective activation of specific genes and the silencing of others — the same DNA is used differently in each cell type
SOMAPL13 Advanced Test — Complete
Cell Structure and Function — 100 Questions — Based on Martini Essentials of A&P
-- correct
-- incorrect
100 total