Topic 8 Thermoregulation

Question 1

Homeostasis

Answer 1

regulation of an internal environment in the face of changes in the external environment

Question 2

Sensor

Answer 2

detects environmental conditions

Question 3

neg feedback is

Answer 3

homeostatic

Question 4

integrators

Answer 4

analyzes signals from sensor, compares conditions to the set point and activates an appropriate effector

Question 5

Effector

Answer 5

causes an physiological change that opposes the deviation from the set point

Question 6

sensory receptors to integrator (type of neuron)

Answer 6

afferent

Question 7

Integrator to effectors (type of neuron)

Answer 7

efferent

Question 8

Positive feedback Mechanisms +ex (3)

Answer 8

A change in a variable under homeostatic control triggers a response that amplifies the change

no shutting off until stimulus is removed

Ex: baby rush cervix, stimulus secretes oxytocin, oxytocin carried to uterus via blood stimulates uterus o contract more

Question 9

Ta (3)

Answer 9

Ambient temperature

dictates how much energy animals need to spend to thermoregulate

room temp

Question 10

Constant body temp importance (2)

Answer 10

enzymes can function normally

allows animals to expand and live in diff habitats

Question 11

byproduct of metabolism

Answer 11

Heat

Question 12

heat can be exchanged with the environment by

Answer 12

conduction, convection, and radiation

Question 13

conductance

Answer 13

rate of heat exchange

Question 14

explain what ectotherm and endotherm do with body heat

Answer 14

ectotherm just release, no thermoregulate

endotherm generate body heat to thermoregulate

Question 15

large organism and conductance relationship

Answer 15

large organisms have lower conductance due to smaller SA/V ratio

Question 16

Smaller organisms and conductance relationship

Answer 16

larger sa/v ration so higher conductance

Question 17

Homeotherms (2)

Answer 17

Maintains “Constant body temp” independent of ambient temp

can be endotherm or ectotherms

Question 18

Heterotherm+advantage+ ex (3)

Answer 18

body temperature fluctuates with ambient tempt

*advantages of reducing metabolic rate

Ex: fresh water fish whose Tb changes with seasonal changes in the water temp

Question 19

Endotherms (2)

Answer 19

Uses metabolism to generate body heat

internal heat generation

Question 20

Ectotherms (2)

Answer 20

Acquires body heat from temperature in environment

external heat source

Question 21

Regional heterothermy +ex (2)

Answer 21

different between different regions of the body. Organisms that are able to maintain different temperature zones in different regions of the body

ex: if you take a fish, a measure the temp, the closer it s to the skin, the more its like water temp

Question 22

countercurrent heat exchange system

Answer 22

a mechanism where warm blood from inner bodies is pumped out to their extremities next to the cold blood running back inwards The 2 blood temp participate in heat exchange and cold blood is warmed before re-entry to the body core

Question 23

Fundamental concept (2)

Answer 23

Endotherms have higher RMR the ectotherms

Ectotherms with same body mass have much lower RMR

Question 24

Regardless of endo and ecto whats the relationship btwn mass and msmr?

Answer 24

as body mass increase, mass specific metabolic rate goes down as the SA:V ratio decreases as animal increase in size

Question 25

Total metabolic rate and rmr relationship and difference

Answer 25

Total metabolic rate is porportional to RMR the difference btwn the two is rmr doesn’t account for your active metabolic rate

as temp increase, there is a proportional change between rmr and total metabolic rate

Question 26

at low temp, enzymes are

Answer 26

inactive

Question 27

At high temp, enzymes are

Answer 27

denatured

Question 28

rmr vs ambient temp graph. homeothermic

Answer 28

slide 16 topic 8

Question 29

how to reduce heat loss

Answer 29

decrease exposure/ sa

Question 30

what body will do to thermoregulate at hypothermia (5) *Term solutions

homeotherms

Answer 30

shivering
vasoconstriction (minimize heat loss)
philoerection (fur stands up and traps air inside insulting the insulating layer of air around body)
decrease SA ( fold into ball)
decrease exposure (burrowing)

Question 31

What body will do in hyperthermia *Term solutions

homeotherms (5)

Answer 31

panting (When air comes in contact with the most pinning of lungs, it helps animal reduce its body temp
vasodilation
sweating
increase SA
decrease exposure (to sun)

Question 32

low conductance is an adaptation (such as…) for (2)

Answer 32

heat retention

(fats/fur)

Question 33

high conductance is an adaptation (such as) for (2)

Answer 33

heat loss
thin skin

Question 34

for arctic animals, temp…

Answer 34

does not impact metabolic rate du to adaptations

Question 35

Ambient temp and metabolic rate in a heterethermic ectotherm

Answer 35

pg19 topic 8

Question 36

lethargy (2)

Answer 36

slow and inactive movements while the animals are awake – they are moving, but slowly.
conserving energy

Question 37

grouping (2)

Answer 37

huddling tgt to share radiation

ex: reposting help bat reduce metabolic expenditure on temp regulation

Question 38

Tarpor (4)

Answer 38

Use of non-shivering thermogenesis during recovery

Approximate 10°C drop in body temperature

A few hours duration

Reduced metabolic rate

Question 39

getting ready for migration

Answer 39

store energy reserve

exercise certain muscles

Question 40

acclimation

Answer 40

organisms adjust their cellular conditions to work optimally in cold and warm environments

Question 41

vasoconstrictions in endotherms

Answer 41

when cold to retain heat

Question 42

Vasoconstriction in ectotherms

Answer 42

when hot to retain heat

Question 43

Vasodilation for ectotherms

Answer 43

when cold to retain heat

Question 44

how does animals are up from hibernation

Answer 44

non shivering thermogenesis