Homeostasis

Question 1

What are the choices/trade-offs an individual must make?

Answer 1

(1) Fecundity (reproduction)
(2) Growth
(3) Longevity

Question 2

Fecundity

Answer 2

Reproduction. How many offspring can you produce and with what investment?

Question 3

Growth

Answer 3

Size/defense (survival). How big and strong or well defended?

Question 4

Longevity

Answer 4

How long will the individual survive?

Question 5

Adaptation

Answer 5

Altering the physiology of a population through changes in gene frequencies over generations.

Question 6

Acclimation

Answer 6

Changing INDIVIDUAL physiology to accommodate environmental change

Question 7

How can organisms change to sustain optimal performance?

Answer 7

(1) Acclimation–changing individual physiology to accomodate emnvironmental change in short term
(2) Regulation–behavior, morphology, or physiology that maintains internal temperature and chemistry in a narrow range (e.g. day vs night)

Question 8

Ectotherm

Answer 8

Derives body temperature from EXTERNAL heat source (e.g. lizard)

Question 9

Endotherm

Answer 9

Derives body temperature from INTERNAL heat production (e.g. birds)

Question 10

Poikilotherm

Answer 10

Body temperature = ambient temperature (e.g. fish)

Question 11

Homeotherm

Answer 11

Controls body temperature, keeps constant as ambient temperature changes (e.g. zebras)

Question 12

Stenotherm

Answer 12

Organism only capable of living or surviving within a very narrow temperature

Question 13

Conduction

Answer 13

Diffusion of heat through liquid/solid

Question 14

Convection

Answer 14

Diffusion of heat through gas

Question 15

Radiation

Answer 15

Electromagnetic movement of heat

Question 16

Thermal neutral zone

Answer 16

(Homeotherms) The range of temperatures over which the metabolic rate does not change, lessens the need for swings in energy demand

Question 17

Counter current heat exchange

Answer 17

Blood flows in loops to the cold extremities, so warm blood flowing out warms up the cold blood flowing back in.

Question 18

Thermal inertia

Answer 18

Reducing the rate of heat loss (reducing surface to volume ratio, e.g. curling up)

Question 19

Bradycardia

Answer 19

Slowing of heart rate (dive reflex)

Question 20

Vasoconstriction

Answer 20

When in cold environments, heat tends to get pulled to the core. Blood is shunted from the periphery to minimize exposure to cold temperatures and maintain core temperature.

Question 21

Heat balance in animals

Answer 21

Total stored = metabolism + conduction + convection + radiation + evaporation

Question 22

Heat balance in plants

Answer 22

Total stored = conduction + convection + radiation

Question 23

Water balance in animals

Answer 23

Balance = Ingestion + metabolism + absorption + secretion + evaporation

Question 24

Water balance in plants

Answer 24

Balance = precipitation + evaporation + transpiration

Question 25

Transpiration

Answer 25

Evaporation of water from plant into the air (from leaves)

Question 26

Potential evapotranspiration (PET)

Answer 26

amount of water lost in the environment from evapotranspiration