thermoregulation Flashcards Preview

PHYSIO II > thermoregulation > Flashcards

Flashcards in thermoregulation Deck (46):
1

normal homeothermy is a balance of what?

-hypothermia
-hyperthermia

2

2 general classifications of thermoregulation

-poililotherms
-homeotherms

3

what are poikilotherms?

-ectothermic
-cold-blooded
-variable body temp

4

what are homeotherms?

-endothermic
-warm-blooded
-"constant" body temp

5

what are the advantages of poikilotherms?

1. less energy expenditure
2. food conserving mechanism
3.alter behavior based on external temp

6

what are the disadvantages of poikilotherms?

1. unable to have high year-round productivity**
2. habitat limitations
3. cannot tolerate extremes in temperature

7

are homeotherms or poikilotherms more capable of tolerating environmental extremes?

homeotherms

8

are neonates good at maintaining a constant temperature?

no

9

heat production has to equal=

heat loss

10

do we lose more animals due to heat stress or cold stress?

heat stress

11

radiation, conduction and convection are dependent on:

temperature gradient

12

delta Tc should be close to/equal to what

zero

13

what is raditaion?

transfer of heat between NON-TOUCHING objects can be a loss or a gain

14

what is conduction?

transfer of heat between TOUCHING objects can be a gain or loss

15

what are the two biggest avenues of heat exchange?

-convection
-evaporation

16

what is convection?

transfer of heat via a FLUID medium
-i.e air, blood, water

17

what is the most common way we transfer heat?

through the blood

18

what are the 2 types of convection?

natural and forced

19

what is natural convection?

warmed air move away from the body occurs in still air situations

20

what is forced convection?

moving air or fluid over surface

21

always beware of what?

drafts

22

what is a great insulator?

air

23

what are great conductors?

water and blood

24

what is evaporation?

transfer of heat as a liquid is converted to a gas

25

what is evaporation highly influenced by?

relative humidity

26

T/F: evaporation is always a loss.

true

27

you have to live in an environment above what?

rectal temp

28

what type of heat transfers heat to the lung surface?

convection

29

what is vital to survive in heat stress?

evaporation

30

if you block evaporation, you must increase _______ or decrease ____.

-other losses
-heat gain

31

aprocine sweat gland have what kind of secretions?

protein

32

eccrine sweat glands have what kind of secretions?

aqueous

33

homeotherms must make (more/less) heat production.

more

34

heat production is proportionate to what?

metabolic size

35

heat loss is in proportion to what?

surface area

36

exercise increases what?

basal metabolic rate

37

hormone of metabolic rate

thyroxine, testosterone

38

do younger or older animals have a higher BMR?

younger

39

the is Bergmann's Rule

in colder climates, animals will be larger

40

characteristics of hiberation

-reduced metabolic rate ~25% of normal
-lower body temp
-reduced HR

41

ways to increase heat production:

-shivering
-digestion
-non-shivering thermogenesis
-brown fat
-exercise

42

to lose heat, we must get it where?

to the surface

43

are tissues/air good conductors?

no

44

what is vital to control of hyperthermia?

blood brain temperature

45

what increases heat capacity?

hydration

46

Mount;s concept of thermalnutrality

-there's a wide range of temperature (*balance)
1. comfortability
2. choice
3. max health
4. lowest mainentance
5. max gain and feed efficiency