,BIOD 102 Module 4 | Q&A | 2026/2027 | Essential Biology | Portage
Learning
1. Homeostasis is best defined as:
A) The process of maintaining a constant external environment
B) The maintenance of equilibrium/set points within the internal environment
C) The ability to respond to external stimuli
D) The process of breaking down food for energy
Correct Answer: The maintenance of equilibrium/set points within the internal
environment
Rationale: Homeostasis is the maintenance of equilibrium, set points, or
standard ranges within the internal environment of an organism. It involves
regulating variables such as temperature, pH, and blood glucose to maintain
stable internal conditions despite external changes.
2. Which of the following is an example of positive feedback regulation?
A) Body temperature regulation
B) Blood glucose regulation
C) Blood clotting cascade
D) Blood pressure regulation
Correct Answer: Blood clotting cascade
Rationale: The blood clotting cascade is an example of positive feedback,
where the response amplifies the initial stimulus. As clotting factors are
activated, they activate more clotting factors, amplifying the response until
the clot is formed.
,3. Negative feedback regulation is characterized by:
A) The response amplifying the initial stimulus
B) The response counteracting the initial stimulus to maintain a set point
C) The response having no effect on the initial stimulus
D) The response varying randomly
Correct Answer: The response counteracting the initial stimulus to maintain a
set point
Rationale: Negative feedback is a regulatory mechanism where the response
counteracts the initial stimulus to maintain homeostasis and return the
system to a set point. Examples include thermoregulation, blood glucose
regulation, and blood pressure control.
4. Thermoregulation is an example of:
A) Positive feedback
B) Negative feedback
C) Feed-forward regulation
D) Non-homeostatic regulation
Correct Answer: Negative feedback
Rationale: Thermoregulation is an example of negative feedback, where the
body responds to deviations from the set point temperature by initiating
responses (sweating or shivering) that counteract the change and return the
body to the normal temperature range.
5. Which of the following is NOT typically regulated by homeostatic
mechanisms?
, A) Blood glucose levels
B) Body temperature
C) Blood pressure
D) Voluntary muscle movement
Correct Answer: Voluntary muscle movement
Rationale: Homeostatic mechanisms regulate internal variables such as
blood glucose, body temperature, blood pressure, pH, and calcium balance.
Voluntary muscle movement is controlled by the somatic nervous system
and is not a homeostatically regulated variable.
6. Osmoregulation refers to the regulation of:
A) Blood glucose levels
B) Body temperature
C) Water and solute balance
D) Blood pressure
Correct Answer: Water and solute balance
Rationale: Osmoregulation is the process by which organisms regulate water
and solute balance to maintain proper osmotic pressure in body fluids. This is
essential for maintaining cell volume and function.
7. The set point for human body temperature is approximately:
A) 35.0°C
B) 36.5°C
C) 37.0°C
Learning
1. Homeostasis is best defined as:
A) The process of maintaining a constant external environment
B) The maintenance of equilibrium/set points within the internal environment
C) The ability to respond to external stimuli
D) The process of breaking down food for energy
Correct Answer: The maintenance of equilibrium/set points within the internal
environment
Rationale: Homeostasis is the maintenance of equilibrium, set points, or
standard ranges within the internal environment of an organism. It involves
regulating variables such as temperature, pH, and blood glucose to maintain
stable internal conditions despite external changes.
2. Which of the following is an example of positive feedback regulation?
A) Body temperature regulation
B) Blood glucose regulation
C) Blood clotting cascade
D) Blood pressure regulation
Correct Answer: Blood clotting cascade
Rationale: The blood clotting cascade is an example of positive feedback,
where the response amplifies the initial stimulus. As clotting factors are
activated, they activate more clotting factors, amplifying the response until
the clot is formed.
,3. Negative feedback regulation is characterized by:
A) The response amplifying the initial stimulus
B) The response counteracting the initial stimulus to maintain a set point
C) The response having no effect on the initial stimulus
D) The response varying randomly
Correct Answer: The response counteracting the initial stimulus to maintain a
set point
Rationale: Negative feedback is a regulatory mechanism where the response
counteracts the initial stimulus to maintain homeostasis and return the
system to a set point. Examples include thermoregulation, blood glucose
regulation, and blood pressure control.
4. Thermoregulation is an example of:
A) Positive feedback
B) Negative feedback
C) Feed-forward regulation
D) Non-homeostatic regulation
Correct Answer: Negative feedback
Rationale: Thermoregulation is an example of negative feedback, where the
body responds to deviations from the set point temperature by initiating
responses (sweating or shivering) that counteract the change and return the
body to the normal temperature range.
5. Which of the following is NOT typically regulated by homeostatic
mechanisms?
, A) Blood glucose levels
B) Body temperature
C) Blood pressure
D) Voluntary muscle movement
Correct Answer: Voluntary muscle movement
Rationale: Homeostatic mechanisms regulate internal variables such as
blood glucose, body temperature, blood pressure, pH, and calcium balance.
Voluntary muscle movement is controlled by the somatic nervous system
and is not a homeostatically regulated variable.
6. Osmoregulation refers to the regulation of:
A) Blood glucose levels
B) Body temperature
C) Water and solute balance
D) Blood pressure
Correct Answer: Water and solute balance
Rationale: Osmoregulation is the process by which organisms regulate water
and solute balance to maintain proper osmotic pressure in body fluids. This is
essential for maintaining cell volume and function.
7. The set point for human body temperature is approximately:
A) 35.0°C
B) 36.5°C
C) 37.0°C
