Question 1

Which of the following best describes homeostasis in animals?

Accepted Answer

The ability to maintain a constant internal environment despite changes in the external environment.

Question 2

A lizard basks in the sun to raise its body temperature, then moves into the shade to cool down. This is an example of:

Accepted Answer

Behavioral thermoregulation

Question 3

Which of the following is a physiological adaptation for thermoregulation in mammals?

Accepted Answer

Vasodilation of blood vessels near the skin surface when hot

Question 4

Homeotherms differ from poikilotherms in that homeotherms:

Accepted Answer

Maintain a relatively constant internal body temperature regardless of external conditions.

Question 5

Which equation represents the temperature coefficient ($$Q_{10}) $$used to measure the sensitivity of a physiological process to temperature?

Accepted Answer

$$Q_{10} = \frac{R_2$}{R_1$}^{10/(T_2$-T_1$)}$$

Question 6

Which of the following is an example of negative feedback in animal physiology?

Accepted Answer

Sweating to cool the body when overheated

Question 7

Why is thermoregulation important for enzyme function in animals?

Accepted Answer

Enzyme-catalyzed reaction rates are temperature-dependent and must be coordinated for metabolism.

Question 8

Which of the following best describes a feedforward control system in animal physiology?

Accepted Answer

A system that anticipates changes and initiates responses before deviations occur.

Question 9

Which adaptation would most likely help a small mammal survive in a cold microenvironment?

Accepted Answer

Hibernation with reduced body temperature and metabolic rate

Question 10

Which of the following is a real-world example of countercurrent heat exchange in animals?

Accepted Answer

The arrangement of arteries and veins in the legs of wading birds

Question 11

A frog's body temperature drops at night and rises during the day, closely matching the ambient temperature. This frog is best classified as:

Accepted Answer

A poikilotherm

Question 12

Which of the following is NOT a parameter commonly regulated by homeostasis in animals?

Accepted Answer

External humidity

Question 13

Which of the following statements about microenvironments is correct?

Accepted Answer

Microenvironments within a habitat can provide different conditions that help animals survive extreme external environments.

Question 14

Which of the following is an example of positive feedback in animal physiology?

Accepted Answer

Oxytocin release during childbirth amplifying uterine contractions

Question 15

Which of the following best explains why large-bodied animals have more options for thermoregulation than small-bodied animals?

Accepted Answer

Large animals have a lower surface area-to-volume ratio, reducing heat loss.

Question 16

Which of the following is a correct statement about endotherms?

Accepted Answer

Endotherms generate most of their heat from internal metabolism.

Question 17

During hibernation, what happens to the body temperature and metabolic rate of a small mammal?

Accepted Answer

Both body temperature and metabolic rate decrease significantly.

Question 18

Which of the following is a plausible consequence if an animal fails to maintain homeostasis of blood pH?

Accepted Answer

Acidosis or alkalosis, which can lead to death if not corrected

Question 19

A desert rodent survives extreme heat by burrowing underground during the day and emerging at night. This strategy primarily utilizes:

Accepted Answer

Microenvironment selection for behavioral thermoregulation

Question 20

Which of the following best illustrates the concept of molecular evolution in animal diversity?

Accepted Answer

Changes in genes that allow animals to adapt to different thermal environments

Animal Homeostasis: Principles and Mechanisms

Study Guide - Practice Questions