SCI 221 Exam 1 V2 | SCI 221 Human
Physiology with Intervention Skill-Based
(ISB) Experiential Learning | Q&A with
Rationale (SCI221 Exam 1) | Nightingale
College
1. A patient presents with a core temperature of 102 degrees Fahrenheit. Which component
of the homeostatic control system is responsible for interpreting this information and
determining the appropriate response?
A. The Receptor
B. The Control Center
C. The Effector
D. The Stimulus
Correct Answer: B
Rationale: The control center, typically the hypothalamus in the brain, receives input from
receptors and compares it to the physiological set point. Once the deviation is identified, it
sends signals to effectors to initiate a corrective response. This process ensures that body
temperature remains within a narrow, functional range through negative feedback.
,2. During the process of childbirth, the stretching of the cervix triggers the release of
oxytocin, which further increases uterine contractions. This is an example of which
physiological mechanism?
A. Negative Feedback
B. Homeostatic Equilibrium
C. Positive Feedback
D. Afferent Inhibition
Correct Answer: C
Rationale: Positive feedback loops serve to amplify a stimulus rather than reverse it,
pushing the system further away from the starting point. In labor, the increased
contractions lead to more cervical stretching, which stimulates more oxytocin release until
delivery occurs. This mechanism is rare in the body but essential for specific events like
blood clotting and parturition.
3. Which level of structural organization is defined as a group of similar cells working together
to perform a specific function?
A. Organ Level
B. Chemical Level
C. Cellular Level
D. Tissue Level
, Correct Answer: D
Rationale: The tissue level represents the next step of complexity above the cellular level,
where specialized cells aggregate to perform tasks like contraction or signaling. There are
four primary types of tissues in the human body: epithelial, connective, muscle, and
nervous. Multiple tissues then combine to form the organ level of organization.
4. What is the primary function of the phospholipid bilayer in the plasma membrane?
A. To facilitate active transport of large proteins
B. To act as a selective barrier to water-soluble substances
C. To provide structural support for the cytoskeleton
D. To synthesize ATP for cellular energy
Correct Answer: B
Rationale: The amphipathic nature of phospholipids allows them to form a bilayer with
hydrophobic tails facing inward, creating a barrier to polar molecules. This structure is
critical for maintaining distinct internal and external environments for the cell. Only lipid-
soluble substances or small nonpolar molecules can easily diffuse across this hydrophobic
core.
5. A nurse administers an intravenous solution that is hypertonic to the patient’s blood. What
is the expected physiological effect on the red blood cells?
A. The cells will swell and burst (hemolysis)
B. The cells will remain unchanged
Physiology with Intervention Skill-Based
(ISB) Experiential Learning | Q&A with
Rationale (SCI221 Exam 1) | Nightingale
College
1. A patient presents with a core temperature of 102 degrees Fahrenheit. Which component
of the homeostatic control system is responsible for interpreting this information and
determining the appropriate response?
A. The Receptor
B. The Control Center
C. The Effector
D. The Stimulus
Correct Answer: B
Rationale: The control center, typically the hypothalamus in the brain, receives input from
receptors and compares it to the physiological set point. Once the deviation is identified, it
sends signals to effectors to initiate a corrective response. This process ensures that body
temperature remains within a narrow, functional range through negative feedback.
,2. During the process of childbirth, the stretching of the cervix triggers the release of
oxytocin, which further increases uterine contractions. This is an example of which
physiological mechanism?
A. Negative Feedback
B. Homeostatic Equilibrium
C. Positive Feedback
D. Afferent Inhibition
Correct Answer: C
Rationale: Positive feedback loops serve to amplify a stimulus rather than reverse it,
pushing the system further away from the starting point. In labor, the increased
contractions lead to more cervical stretching, which stimulates more oxytocin release until
delivery occurs. This mechanism is rare in the body but essential for specific events like
blood clotting and parturition.
3. Which level of structural organization is defined as a group of similar cells working together
to perform a specific function?
A. Organ Level
B. Chemical Level
C. Cellular Level
D. Tissue Level
, Correct Answer: D
Rationale: The tissue level represents the next step of complexity above the cellular level,
where specialized cells aggregate to perform tasks like contraction or signaling. There are
four primary types of tissues in the human body: epithelial, connective, muscle, and
nervous. Multiple tissues then combine to form the organ level of organization.
4. What is the primary function of the phospholipid bilayer in the plasma membrane?
A. To facilitate active transport of large proteins
B. To act as a selective barrier to water-soluble substances
C. To provide structural support for the cytoskeleton
D. To synthesize ATP for cellular energy
Correct Answer: B
Rationale: The amphipathic nature of phospholipids allows them to form a bilayer with
hydrophobic tails facing inward, creating a barrier to polar molecules. This structure is
critical for maintaining distinct internal and external environments for the cell. Only lipid-
soluble substances or small nonpolar molecules can easily diffuse across this hydrophobic
core.
5. A nurse administers an intravenous solution that is hypertonic to the patient’s blood. What
is the expected physiological effect on the red blood cells?
A. The cells will swell and burst (hemolysis)
B. The cells will remain unchanged
