Lecture 9: Temperature Regulation Flashcards Preview

Zak, Physiology 2 > Lecture 9: Temperature Regulation > Flashcards

Flashcards in Lecture 9: Temperature Regulation Deck (17):
0

Loss in the form of infrared heat rays is _____.

Radiation

1

Removal of heat from the body by air currents is _____.

Convection

2

KE of molecules of the skin is transferred to the air if the air is colder than the skin is termed _____.

Conduction

3

What causes a continual heat loss at a rate of 16-19 Calories/day?

Insensible perspiration

4

What must be stimulated for sweating to occur?

Anterior hypothalamus-pre-optic area

5

T/F: The anterior pre-optic area contains only heat-sensitive neurons.

False, also cold-sensitive neurons

6

_____ of skin vessels is caused by inhibition of sympathetic centers in posterior hypothalamus

Vasodilation

7

Skin vasoconstriction, piloerection, & increased thermogenesis are all mechanisms to _____ body heat.

Increase

8

Vasodilation of skin vessels, sweating, & decrease heat production are all mechanisms of _____ body heat.

Reducing

9

Where is the primary motor area for shivering?

Dorsomedial portion of posterior hypothalamus

10

The dorsomedial portion of the posterior hypothalamus is normally _____ by signals from the heat center in anterior hypothalamic pre-optic area.

Inhibited

11

What is chemical thermogenesis?

Increase in rate of cellular metabolism due to sympathetic stimulation

12

What is the set-point for thermal control?

37.1˚C/98.8˚F
Level at which sweating or shivering begins in order to return to critical core body temperature

13

What are some examples of pyrogens?

Proteins, breakdown products of proteins, & lipopolysaccharides

14

How does Aspirin reduce fever?

It prevents IL-1 from producing prostaglandins from arachidonic acid

15

When is heat stroke likely to occur?

Heavy work conditions in environmental temperature of as low as 85-90˚F

16

At what temperature does the hypothalamus lose function?

85˚F