ASU BIO360 ANIMAL
PHYSIOLOGY EXAM 1
PRACTICE EXAM
Question 1: After a carbohydrate-rich meal, plasma glucose rises and insulin
promotes glucose uptake until plasma glucose moves back toward its usual range.Which variable is being regulated in this negative-feedback system?
Choices:
1) Rate of intestinal absorption 2) Insulin concentration 3) Plasma glucose concentration 4) Number of insulin receptors
Correct Answer: Plasma glucose concentration
Explanation: The regulated variable is plasma glucose concentration. Insulin is part of the response that counteracts the initial rise in glucose and returns the regulated variable toward its normal range.Page 1
Question 2: Which situation is the clearest example of positive feedback rather than negative feedback?
Choices:
1) Sweating when body temperature rises 2) Insulin release after blood glucose increases 3) Platelet activation recruiting additional platelets at a damaged vessel 4) Increasing ventilation when arterial carbon dioxide rises Correct Answer: Platelet activation recruiting additional platelets at a damaged vessel Explanation: Positive feedback ampli�es the initiating change. Activated platelets release signals that recruit and activate additional platelets, accelerating clot formation until the break is sealed.
Question 3: A homeostatic control system senses a fall in arterial pressure,
compares that information with a target range, and increases sympathetic output.Which component performs the comparison and coordinates the response?
Choices:
1) E�ector 2) Integrating center 3) Controlled variable 4) Environmental input
Correct Answer: Integrating center
Explanation: The integrating center receives sensory information, compares it with the desired range or set point, and sends output commands to e�ectors.Page 2
Question 4: Researchers assign healthy adults to receive 0 mg, 100 mg, or 200 mg of ca�eine and then measure heart rate 30 minutes later. What is the independent variable?
Choices:
1) Ca�eine dose 2) Participant age 3) Heart rate 4) Time after ingestion
Correct Answer: Ca�eine dose
Explanation: The independent variable is the factor deliberately manipulated by the investigators. Here that factor is ca�eine dose.
Question 5: A physiologist measures the same group of desert rodents every six
months for four years to determine how resting metabolic rate changes with age.What type of study design is this?
Choices:
1) Case-control 2) Cross-sectional 3) Longitudinal 4) Single-blind crossover
Correct Answer: Longitudinal
Explanation: A longitudinal study repeatedly measures the same individuals over time. A cross- sectional study instead compares di�erent individuals at one point in time.Page 3