BIO 201 EXAM – ANATOMY AND
PHYSIOLOGY I QUESTIONS WITH
CORRECT ANSWERS (LATEST 2026 /
2027), (A+ GUARANTEE).
1. Which of the following best describes the physiological process of homeostatic negative
feedback?
A. The effector enhances the stimulus to move the variable further from the set point.
B. The control center ignores the stimulus if the change is within 10% of the set point.
C. The receptor acts as the primary driver to stimulate a cascading hormonal response.
D. The effector opposes the stimulus to restore the variable toward the set point.
Answer: D
Conceptual Explanation: Negative feedback works to negate or reverse a change in a
controlled condition, bringing it back toward a set point, unlike positive feedback which
amplifies the change.
2. A protein that is embedded within the phospholipid bilayer and spans the entire width of
the membrane is characterized as:
A. A peripheral protein
B. A transmembrane integral protein
,C. A glycoprotein residing only on the glycocalyx
D. A lipid-anchored protein
Answer: B
Conceptual Explanation: Integral proteins are embedded in the membrane, and those that
span the entire membrane are specifically called transmembrane proteins.
3. During the depolarization phase of an action potential in a neuron, which of the following
occurs?
A. Voltage-gated K+ channels open rapidly.
B. The Na+/K+ pump reverses its direction of ion transport.
C. The membrane potential becomes more negative than the resting potential.
D. Voltage-gated Na+ channels open, allowing Na+ to flow into the cell.
Answer: D
Conceptual Explanation: Depolarization is caused by the rapid influx of sodium ions
(Na+) through voltage-gated channels, making the interior of the cell more positive.
4. In the sliding filament model of muscle contraction, what is the specific role of Calcium ions
(Ca2+)?
A. Binding to tropomyosin to uncover the myosin-binding sites.
B. Hydrolyzing ATP into ADP and Inorganic Phosphate on the myosin head.
C. Binding to troponin, which then shifts tropomyosin away from actin binding sites.
, D. Providing the electrical charge needed for the T-tubule depolarization.
Answer: C
Conceptual Explanation: Calcium binds to troponin, inducing a conformational change
that moves tropomyosin, thereby exposing the active sites on actin for myosin attachment.
5. Which type of epithelial tissue is best adapted for rapid diffusion and filtration, such as in
the alveoli of the lungs?
A. Simple cuboidal epithelium
B. Simple squamous epithelium
C. Stratified squamous epithelium
D. Transitional epithelium
Answer: B
Conceptual Explanation: Simple squamous epithelium consists of a single layer of flat
cells, providing the thinnest possible barrier for rapid diffusion.
6. The ‘All-or-None’ principle of action potentials states that:
A. All neurons in a nerve fire simultaneously or not at all.
B. The amplitude of an action potential is proportional to the strength of the stimulus.
C. An action potential happens completely or not at all once threshold is reached.
D. The speed of conduction is identical for all axons regardless of myelination.
PHYSIOLOGY I QUESTIONS WITH
CORRECT ANSWERS (LATEST 2026 /
2027), (A+ GUARANTEE).
1. Which of the following best describes the physiological process of homeostatic negative
feedback?
A. The effector enhances the stimulus to move the variable further from the set point.
B. The control center ignores the stimulus if the change is within 10% of the set point.
C. The receptor acts as the primary driver to stimulate a cascading hormonal response.
D. The effector opposes the stimulus to restore the variable toward the set point.
Answer: D
Conceptual Explanation: Negative feedback works to negate or reverse a change in a
controlled condition, bringing it back toward a set point, unlike positive feedback which
amplifies the change.
2. A protein that is embedded within the phospholipid bilayer and spans the entire width of
the membrane is characterized as:
A. A peripheral protein
B. A transmembrane integral protein
,C. A glycoprotein residing only on the glycocalyx
D. A lipid-anchored protein
Answer: B
Conceptual Explanation: Integral proteins are embedded in the membrane, and those that
span the entire membrane are specifically called transmembrane proteins.
3. During the depolarization phase of an action potential in a neuron, which of the following
occurs?
A. Voltage-gated K+ channels open rapidly.
B. The Na+/K+ pump reverses its direction of ion transport.
C. The membrane potential becomes more negative than the resting potential.
D. Voltage-gated Na+ channels open, allowing Na+ to flow into the cell.
Answer: D
Conceptual Explanation: Depolarization is caused by the rapid influx of sodium ions
(Na+) through voltage-gated channels, making the interior of the cell more positive.
4. In the sliding filament model of muscle contraction, what is the specific role of Calcium ions
(Ca2+)?
A. Binding to tropomyosin to uncover the myosin-binding sites.
B. Hydrolyzing ATP into ADP and Inorganic Phosphate on the myosin head.
C. Binding to troponin, which then shifts tropomyosin away from actin binding sites.
, D. Providing the electrical charge needed for the T-tubule depolarization.
Answer: C
Conceptual Explanation: Calcium binds to troponin, inducing a conformational change
that moves tropomyosin, thereby exposing the active sites on actin for myosin attachment.
5. Which type of epithelial tissue is best adapted for rapid diffusion and filtration, such as in
the alveoli of the lungs?
A. Simple cuboidal epithelium
B. Simple squamous epithelium
C. Stratified squamous epithelium
D. Transitional epithelium
Answer: B
Conceptual Explanation: Simple squamous epithelium consists of a single layer of flat
cells, providing the thinnest possible barrier for rapid diffusion.
6. The ‘All-or-None’ principle of action potentials states that:
A. All neurons in a nerve fire simultaneously or not at all.
B. The amplitude of an action potential is proportional to the strength of the stimulus.
C. An action potential happens completely or not at all once threshold is reached.
D. The speed of conduction is identical for all axons regardless of myelination.
