PORTAGE LEARNING BIOL 271
MODULE 1 EXAM QUESTIONS AND
ANSWERS
1. Which of the following cellular components is primarily responsible for the synthesis of
phospholipids and the detoxification of drugs and poisons?
A. Smooth Endoplasmic Reticulum
B. Golgi Apparatus
C. Rough Endoplasmic Reticulum
D. Lysosomes
Answer: A
Conceptual Explanation: The smooth endoplasmic reticulum (SER) is involved in lipid
synthesis, including phospholipids, and plays a crucial role in detoxifying chemicals.
2. In the process of active transport, the sodium-potassium pump (Na+/K+ ATPase) moves
ions against their concentration gradient. What is the correct ratio of ions moved?
A. 2 Na+ out, 3 K+ in
B. 3 Na+ out, 2 K+ in
,C. 3 Na+ in, 2 K+ out
D. 2 Na+ in, 3 K+ out
Answer: B
Conceptual Explanation: The Na+/K+ pump uses ATP to transport three sodium ions out
of the cell and two potassium ions into the cell, maintaining electrical gradients.
3. A patient exhibits a decrease in muscle mass due to prolonged bed rest. This cellular
adaptation is best described as:
A. Physiologic hypertrophy
B. Pathologic hyperplasia
C. Metaplasia
D. Disuse atrophy
Answer: D
Conceptual Explanation: Atrophy is the decrease in cell size; disuse atrophy specifically
occurs when muscle cells shrink due to lack of physical activity.
4. Which type of cellular adaptation involves the replacement of one mature cell type with
another mature cell type, often due to chronic irritation?
A. Dysplasia
B. Hyperplasia
C. Hypertrophy
, D. Metaplasia
Answer: D
Conceptual Explanation: Metaplasia is a reversible change where one adult cell type
(epithelial or mesenchymal) is replaced by another adult cell type to withstand stress.
5. Dysplasia is often characterized by which of the following features?
A. Uniformity of cell shape and size
B. A specific change from columnar to squamous epithelium
C. Increased number of normal cells
D. Deranged cell growth with varying size, shape, and organization
Answer: D
Conceptual Explanation: Dysplasia refers to abnormal changes in the size, shape, and
organization of mature cells and is often a precursor to cancer.
6. Which mechanism is the most common cause of cellular injury?
A. Free radical formation
B. Hypoxia
C. Chemical agents
D. Genetic defects
Answer: B
MODULE 1 EXAM QUESTIONS AND
ANSWERS
1. Which of the following cellular components is primarily responsible for the synthesis of
phospholipids and the detoxification of drugs and poisons?
A. Smooth Endoplasmic Reticulum
B. Golgi Apparatus
C. Rough Endoplasmic Reticulum
D. Lysosomes
Answer: A
Conceptual Explanation: The smooth endoplasmic reticulum (SER) is involved in lipid
synthesis, including phospholipids, and plays a crucial role in detoxifying chemicals.
2. In the process of active transport, the sodium-potassium pump (Na+/K+ ATPase) moves
ions against their concentration gradient. What is the correct ratio of ions moved?
A. 2 Na+ out, 3 K+ in
B. 3 Na+ out, 2 K+ in
,C. 3 Na+ in, 2 K+ out
D. 2 Na+ in, 3 K+ out
Answer: B
Conceptual Explanation: The Na+/K+ pump uses ATP to transport three sodium ions out
of the cell and two potassium ions into the cell, maintaining electrical gradients.
3. A patient exhibits a decrease in muscle mass due to prolonged bed rest. This cellular
adaptation is best described as:
A. Physiologic hypertrophy
B. Pathologic hyperplasia
C. Metaplasia
D. Disuse atrophy
Answer: D
Conceptual Explanation: Atrophy is the decrease in cell size; disuse atrophy specifically
occurs when muscle cells shrink due to lack of physical activity.
4. Which type of cellular adaptation involves the replacement of one mature cell type with
another mature cell type, often due to chronic irritation?
A. Dysplasia
B. Hyperplasia
C. Hypertrophy
, D. Metaplasia
Answer: D
Conceptual Explanation: Metaplasia is a reversible change where one adult cell type
(epithelial or mesenchymal) is replaced by another adult cell type to withstand stress.
5. Dysplasia is often characterized by which of the following features?
A. Uniformity of cell shape and size
B. A specific change from columnar to squamous epithelium
C. Increased number of normal cells
D. Deranged cell growth with varying size, shape, and organization
Answer: D
Conceptual Explanation: Dysplasia refers to abnormal changes in the size, shape, and
organization of mature cells and is often a precursor to cancer.
6. Which mechanism is the most common cause of cellular injury?
A. Free radical formation
B. Hypoxia
C. Chemical agents
D. Genetic defects
Answer: B
