NURS 231/NURS231 Module 1 V2 |
Pathophysiology Q&A with Rationale | Portage
Learning
1. Which organelle is responsible for the primary production of adenosine triphosphate (ATP)
through oxidative phosphorylation?
A. Ribosomes
B. Golgi apparatus
C. Mitochondria
D. Lysosomes
Correct Answer: C
Explanation: Mitochondria are the primary sites of ATP production via the electron
transport chain and oxidative phosphorylation. They are essential for cellular metabolism
and energy-dependent processes like active transport. Impairment of mitochondrial
function often leads to cellular injury and energy depletion.
2. A patient has experienced a decrease in muscle mass due to prolonged bed rest. This
cellular adaptation is known as:
A. Hyperplasia
B. Atrophy
C. Hypertrophy
,D. Metaplasia
Correct Answer: B
Explanation: Atrophy represents a decrease in cell size which results in a reduction of the
total mass of the tissue or organ. This can occur due to disuse, loss of innervation, or
decreased blood supply. It is a survival mechanism that allows the cell to function at a
lower metabolic level.
3. Which type of cellular adaptation involves the replacement of one mature cell type by
another, less differentiated cell type?
A. Metaplasia
B. Dysplasia
C. Anaplasia
D. Hypertrophy
Correct Answer: A
Explanation: Metaplasia is a reversible replacement of one mature cell type by another,
often in response to chronic irritation. A common example is the change in the respiratory
epithelium of smokers from ciliated columnar cells to stratified squamous cells. While it
provides a more durable surface, it often loses the specialized functions of the original
tissue.
4. Dysplasia is most accurately described as:
A. Abnormal changes in the size, shape, and organization of mature cells
, B. The complete absence of an organ
C. A benign increase in the number of normal cells
D. The programmed death of a cell
Correct Answer: A
Explanation: Dysplasia, often called atypical hyperplasia, refers to abnormal changes in
cell morphology and structural organization. It is frequently associated with neoplastic
growth and is commonly found in the cervix or respiratory tract. If the inciting stimulus is
removed, dysplastic changes may be reversible, but they are often considered
precancerous.
5. What is the most common cause of cellular injury in clinical practice?
A. Genetic defects
B. Chemical toxicity
C. Infectious agents
D. Hypoxia
Correct Answer: D
Explanation: Hypoxia, or oxygen deprivation, is the most frequent cause of cellular injury
and can result from ischemia or reduced oxygen-carrying capacity of the blood. Without
oxygen, oxidative phosphorylation ceases, leading to a decrease in ATP production. This
failure triggers a cascade of events including cellular swelling and lactic acid accumulation.
Pathophysiology Q&A with Rationale | Portage
Learning
1. Which organelle is responsible for the primary production of adenosine triphosphate (ATP)
through oxidative phosphorylation?
A. Ribosomes
B. Golgi apparatus
C. Mitochondria
D. Lysosomes
Correct Answer: C
Explanation: Mitochondria are the primary sites of ATP production via the electron
transport chain and oxidative phosphorylation. They are essential for cellular metabolism
and energy-dependent processes like active transport. Impairment of mitochondrial
function often leads to cellular injury and energy depletion.
2. A patient has experienced a decrease in muscle mass due to prolonged bed rest. This
cellular adaptation is known as:
A. Hyperplasia
B. Atrophy
C. Hypertrophy
,D. Metaplasia
Correct Answer: B
Explanation: Atrophy represents a decrease in cell size which results in a reduction of the
total mass of the tissue or organ. This can occur due to disuse, loss of innervation, or
decreased blood supply. It is a survival mechanism that allows the cell to function at a
lower metabolic level.
3. Which type of cellular adaptation involves the replacement of one mature cell type by
another, less differentiated cell type?
A. Metaplasia
B. Dysplasia
C. Anaplasia
D. Hypertrophy
Correct Answer: A
Explanation: Metaplasia is a reversible replacement of one mature cell type by another,
often in response to chronic irritation. A common example is the change in the respiratory
epithelium of smokers from ciliated columnar cells to stratified squamous cells. While it
provides a more durable surface, it often loses the specialized functions of the original
tissue.
4. Dysplasia is most accurately described as:
A. Abnormal changes in the size, shape, and organization of mature cells
, B. The complete absence of an organ
C. A benign increase in the number of normal cells
D. The programmed death of a cell
Correct Answer: A
Explanation: Dysplasia, often called atypical hyperplasia, refers to abnormal changes in
cell morphology and structural organization. It is frequently associated with neoplastic
growth and is commonly found in the cervix or respiratory tract. If the inciting stimulus is
removed, dysplastic changes may be reversible, but they are often considered
precancerous.
5. What is the most common cause of cellular injury in clinical practice?
A. Genetic defects
B. Chemical toxicity
C. Infectious agents
D. Hypoxia
Correct Answer: D
Explanation: Hypoxia, or oxygen deprivation, is the most frequent cause of cellular injury
and can result from ischemia or reduced oxygen-carrying capacity of the blood. Without
oxygen, oxidative phosphorylation ceases, leading to a decrease in ATP production. This
failure triggers a cascade of events including cellular swelling and lactic acid accumulation.
