Animal Energetics

Question 1

what is the metabolic rate?

Answer 1

this is the overall rate of energy used measured as O2 consumption
C6H12O2 + 6O2 -> 6H2O + CO2 +ATP

Question 2

what affects metabolic rate?

Answer 2

activity level: at the start of exercise the O2 consumption rises then falls
Body Size: big animals consume more energy than a small one
body temperature: chemical reactions speed up or slow down with temperature changes

Question 3

what is an endotherm?

Answer 3

this is something that relies on internal heat
when rising temperatures from 0 the metabolic rate of an endo/homeotherm will be very high then drop off at a certain temperature (carrying capacity area)

Question 4

what is an ectotherm?

Answer 4

this relies on outside world to determine body temperature

Question 5

what is a homeotherm?

Answer 5

this has a stable body temperature

Question 6

what is a poikilotherm?

Answer 6

this has a variable body temperature

Question 7

what is a heterotherm?

Answer 7

this can have both (hibernators)

Question 8

how do endotherms use behaviour as a defence mechanism?

Answer 8

when there are normal or cool temperature the arterioles constrict to reduce blood flow
when there are high temperatures the vessels dilate and blood flows to the surface.

Question 9

how do endotherms generate heat?

Answer 9

shivering thermogenesis: skeletal muscles mull against eachother and ATP is converted to ADP
non shivering thermogenesis: occurs in mammals and inside brown adipose tissue which directly produces heat.

Question 10

how do endotherms conserve heat?

Answer 10

evolutionary adaptation: large body sized, and reduced extremities (slender legs, small ears)
insulation: fur and feathers, trapped air

Question 11

how do endotherms avoid overheating?

Answer 11

evaporative cooling: direct contact with water (swimming), panting and sweating
heat windows: rabbit ears, elephant ears