Thermoregulation

Question 1

what are the main thermoregulatory challenges in marine environments

Answer 1

large lat + vertical gradient (thermohaline)

Question 2

thermoregulation

Answer 2

maintaining a constant temp

Question 3

temperature regulation strats

Answer 3

-maintaing constant temp: heterotherm + homeotherms

-temp maintainance: thermoconfromers + thermoregulators

-temp tolerance: eurythermal + stenothermal

-depend on heat source: ectotherm + endotherm

Question 4

avenues of heat transfer

Answer 4

conduction, ceonvection, radiation, evaporation

Question 5

avenues of heat transfer in water

Answer 5

convection, conduction

Question 6

sources of heat for mammals

Answer 6

basal metabolism, thermoregulation, locomotion, heat increment of feeding

Question 7

how to reduce heat loss

Answer 7

reduce SA, have efficient insulation layer, have a thicker insulation layer

Question 8

what occurs in endotherms if they exceed the thermal neutral zone

Answer 8

internal temps increase

Question 9

what occurs in ectotherms if they exceed the thermal neutral zone

Answer 9

temps increase until proteins denature and if below, freezes

Question 10

morphological adaptinos in sp. to cope with heat transfer

Answer 10

larger size, more blubber, dive response, choosing temps/depths (migrtation)

Question 11

what types of mammals rely on fur

Answer 11

small

Question 12

what types of mammals rely on blubber

Answer 12

large and good divers

Question 13

why is blubber a better insulator in water

Answer 13

under high pressure, air in fur is thinner + less effective

Question 14

what pinnipeds rely on fur and which rely on blubber

Answer 14

phocidae: blubber (best divers)
fur seals: fur (most recently adapted)

Question 15

costs of having blubber

Answer 15

adds to buoynacy, constrains size + maneuverability, difficultt o grow/divide live tissues at low temps, must haul-out/move to warmer temps

Question 16

which birds have more blubber and which have more feathers

Answer 16

most feathers: surface feeders (buoyancy)
most blubber: divers

Question 17

pros of fur/feathers

Answer 17

lighter, better insulation for amount, skin can be maintained at/near body temp, ability to repair skin/molt

Question 18

con of fur/feather

Answer 18

needs to be kept clean/groomed, compressible so insulation declines w/ depth, increases drag/reduces hydrodynamics

Question 19

pros of blubber

Answer 19

can withstand fouling, doesn’t compress w/depth, perfuse to bypass + dump heat, energy store, streamlining

Question 20

use of brown adipose tissue

Answer 20

for insulation in newborns

Question 21

using blood to control heat in mammals

Answer 21

countercurrent in jaws + testes

Question 22

using blood to control heat in seabirds

Answer 22

countercurrent in flippers (ss has less blubber for mobility)

Question 23

behavioural strats to maintain heat on land

Answer 23

huddling, lie on top of each other, sand flipping to cool down, use water to cool off

Question 24

behjavioural strats to maintin heat in water

Answer 24

basking, migrate to warmer waters, higher BMR

Question 25

how do endothermic fish maintain heat

Answer 25

swimming muscles are only concentrated around the spine

Question 26

adaptations for deep diving fish to cope with the cold

Answer 26

developed antifreeze gylcoproteins (stop lens crystallisation), phospholipids resistant to cold, developed antifreeze in blood