WGU C190 Introduction to Biology Objective
Assessment Actual 2026/2027 with Detailed Rationales
| 100% Verified | Pass Guaranteed – A+ Graded
SECTION 1: Cell Biology & Structure (14 Questions)
Q1: A biologist examines a cell under a microscope and observes a
membrane-bound nucleus, mitochondria, and a Golgi apparatus. Which conclusion
about this cell is most accurate?
A. It is a prokaryotic cell because it has complex organelles.
B. It is a virus because it has a membrane-bound nucleus.
C. It is a eukaryotic cell because it possesses a membrane-bound nucleus and
membrane-bound organelles. [CORRECT]
D. It is a bacterial cell because it contains mitochondria.
Correct Answer: C
Rationale: The presence of a membrane-bound nucleus and membrane-bound
organelles (mitochondria, Golgi apparatus) are defining characteristics that
distinguish eukaryotic cells from prokaryotic cells.
Q2: Which organelle is responsible for modifying, sorting, and packaging proteins for
secretion or delivery to other organelles?
A. Ribosomes
B. The Golgi apparatus [CORRECT]
C. Lysosomes
D. Peroxisomes
Correct Answer: B
Rationale: The Golgi apparatus receives proteins from the rough ER, modifies them
(e.g., glycosylation), sorts them, and packages them into vesicles for transport to
their final destinations.
Q3: A red blood cell is placed in a hypotonic solution. What will happen to the cell?
A. It will shrink due to water moving out of the cell.
,B. It will remain the same size because water movement is equal.
C. It will swell and potentially burst (lyse) because water moves into the cell by
osmosis. [CORRECT]
D. It will become more concentrated as solutes leave the cell.
Correct Answer: C
Rationale: In a hypotonic solution, the solute concentration is lower outside the cell
than inside, causing water to move into the cell by osmosis down its concentration
gradient.
Q4: Which structure is found in plant cells but NOT in animal cells?
A. Mitochondria
B. Ribosomes
C. Cell wall and chloroplasts [CORRECT]
D. Nucleus
Correct Answer: C
Rationale: Plant cells contain a rigid cell wall composed of cellulose and
chloroplasts for photosynthesis, structures that are absent in animal cells; both cell
types contain mitochondria, ribosomes, and a nucleus.
Q5: During which phase of the cell cycle does DNA replication occur?
A. Prophase
B. Metaphase
C. S phase (Synthesis phase) [CORRECT]
D. G2 phase
Correct Answer: C
Rationale: DNA replication occurs during the S phase of interphase, ensuring that
each daughter cell receives a complete copy of the genome before mitosis begins.
Q6: A cell is observed undergoing division, and the chromosomes are aligned at the
metaphase plate. Which stage of mitosis is this cell in?
A. Prophase
B. Metaphase [CORRECT]
C. Anaphase
D. Telophase
Correct Answer: B
, Rationale: During metaphase, spindle fibers align chromosomes at the cell's
equatorial plane (metaphase plate), a defining characteristic of this mitotic stage.
Q7: Which type of membrane transport requires ATP and moves substances against
their concentration gradient?
A. Facilitated diffusion
B. Simple diffusion
C. Active transport [CORRECT]
D. Osmosis
Correct Answer: C
Rationale: Active transport uses energy (ATP) to move molecules from areas of low
concentration to high concentration, against their natural gradient, unlike passive
transport mechanisms.
Q8: The fluid mosaic model describes the plasma membrane as:
A. A rigid, static layer of phospholipids.
B. A dynamic structure with proteins embedded in a phospholipid bilayer that can
move laterally. [CORRECT]
C. A single layer of phospholipids with cholesterol only.
D. A carbohydrate-only structure with no proteins.
Correct Answer: B
Rationale: The fluid mosaic model describes the plasma membrane as a
phospholipid bilayer with embedded proteins that can move laterally, giving it fluidity
and mosaic-like appearance.
Q9: Which organelle contains digestive enzymes that break down worn-out
organelles and foreign particles?
A. Ribosomes
B. Lysosomes [CORRECT]
C. Smooth ER
D. Centrioles
Correct Answer: B
Rationale: Lysosomes contain hydrolytic enzymes that digest macromolecules,
worn-out organelles, and pathogens, functioning as the cell's recycling and waste
disposal system.
Assessment Actual 2026/2027 with Detailed Rationales
| 100% Verified | Pass Guaranteed – A+ Graded
SECTION 1: Cell Biology & Structure (14 Questions)
Q1: A biologist examines a cell under a microscope and observes a
membrane-bound nucleus, mitochondria, and a Golgi apparatus. Which conclusion
about this cell is most accurate?
A. It is a prokaryotic cell because it has complex organelles.
B. It is a virus because it has a membrane-bound nucleus.
C. It is a eukaryotic cell because it possesses a membrane-bound nucleus and
membrane-bound organelles. [CORRECT]
D. It is a bacterial cell because it contains mitochondria.
Correct Answer: C
Rationale: The presence of a membrane-bound nucleus and membrane-bound
organelles (mitochondria, Golgi apparatus) are defining characteristics that
distinguish eukaryotic cells from prokaryotic cells.
Q2: Which organelle is responsible for modifying, sorting, and packaging proteins for
secretion or delivery to other organelles?
A. Ribosomes
B. The Golgi apparatus [CORRECT]
C. Lysosomes
D. Peroxisomes
Correct Answer: B
Rationale: The Golgi apparatus receives proteins from the rough ER, modifies them
(e.g., glycosylation), sorts them, and packages them into vesicles for transport to
their final destinations.
Q3: A red blood cell is placed in a hypotonic solution. What will happen to the cell?
A. It will shrink due to water moving out of the cell.
,B. It will remain the same size because water movement is equal.
C. It will swell and potentially burst (lyse) because water moves into the cell by
osmosis. [CORRECT]
D. It will become more concentrated as solutes leave the cell.
Correct Answer: C
Rationale: In a hypotonic solution, the solute concentration is lower outside the cell
than inside, causing water to move into the cell by osmosis down its concentration
gradient.
Q4: Which structure is found in plant cells but NOT in animal cells?
A. Mitochondria
B. Ribosomes
C. Cell wall and chloroplasts [CORRECT]
D. Nucleus
Correct Answer: C
Rationale: Plant cells contain a rigid cell wall composed of cellulose and
chloroplasts for photosynthesis, structures that are absent in animal cells; both cell
types contain mitochondria, ribosomes, and a nucleus.
Q5: During which phase of the cell cycle does DNA replication occur?
A. Prophase
B. Metaphase
C. S phase (Synthesis phase) [CORRECT]
D. G2 phase
Correct Answer: C
Rationale: DNA replication occurs during the S phase of interphase, ensuring that
each daughter cell receives a complete copy of the genome before mitosis begins.
Q6: A cell is observed undergoing division, and the chromosomes are aligned at the
metaphase plate. Which stage of mitosis is this cell in?
A. Prophase
B. Metaphase [CORRECT]
C. Anaphase
D. Telophase
Correct Answer: B
, Rationale: During metaphase, spindle fibers align chromosomes at the cell's
equatorial plane (metaphase plate), a defining characteristic of this mitotic stage.
Q7: Which type of membrane transport requires ATP and moves substances against
their concentration gradient?
A. Facilitated diffusion
B. Simple diffusion
C. Active transport [CORRECT]
D. Osmosis
Correct Answer: C
Rationale: Active transport uses energy (ATP) to move molecules from areas of low
concentration to high concentration, against their natural gradient, unlike passive
transport mechanisms.
Q8: The fluid mosaic model describes the plasma membrane as:
A. A rigid, static layer of phospholipids.
B. A dynamic structure with proteins embedded in a phospholipid bilayer that can
move laterally. [CORRECT]
C. A single layer of phospholipids with cholesterol only.
D. A carbohydrate-only structure with no proteins.
Correct Answer: B
Rationale: The fluid mosaic model describes the plasma membrane as a
phospholipid bilayer with embedded proteins that can move laterally, giving it fluidity
and mosaic-like appearance.
Q9: Which organelle contains digestive enzymes that break down worn-out
organelles and foreign particles?
A. Ribosomes
B. Lysosomes [CORRECT]
C. Smooth ER
D. Centrioles
Correct Answer: B
Rationale: Lysosomes contain hydrolytic enzymes that digest macromolecules,
worn-out organelles, and pathogens, functioning as the cell's recycling and waste
disposal system.
