PRACTICE QUESTIONS
1. Sweating is an effective cooling mechanism because:
a. Sweat secretion produces heat, which is carried to the skin surface in the sweat.
b. Conversion of sweat into water vapor requires heat, which is supplied to the skin by blood flow.
c. Sweat dripping from the body carries away large amounts of heat.
d. The ions in sweat carry large amounts of heat from the body.
2. In the cold, animals both conserve and produce heat. Which of the following is a method of heal conservation?
a. Shivering
b. Brown fat metabolism
c. Increased thyroxine secretion
d. Countercurrent heat exchange in the limbs
e. All the above
3. Which of the following methods of heat loss can occur in an animal (body temperature = 38® C) standing in a room (temperature = 40oC) with relative humidity of zero? The walls of the room have a temperature of 30o C.
a. Convection and evaporation
b. Convection and radiation
c. Evaporation and radiation
d. Radiation alone
e. Convection, evaporation, and radiation
4. Which of the following describes thermoregulation?
a. Temperature receptors in both the brain and the skin can initiate thermoregulatory responses.
b. The brain temperature receptors have a greater influence on thermoregulation than do skin receptors.
c. The core temperature at which shivering begins is higher if the skin is cold than if it is warm.
d. Skin cooling can initiate shivering even if core temperature is normal.
e. All the above
5. Which of the following correctly describes fever?
a. It results when the set point for body temperature decreases.
b. It is accompanied by sweating to lose heat as body temperature rises.
c. It is accompanied by shivering to gain heat as body temperature decreases once pyrogens arc metabolized.
d. It can be initiated by pyrogens from bacteria or leukocytes.
e. All the above