Lecture #9 - Physiology

Question 1

parts of a time scale

Answer 1

acute, acclimation, evolutionary

Question 2

why is a short food chain more efficient than a long one?

Answer 2

If only 10% of energy is being transferred, it is not enough to support large populations of organisms that reside in higher trophic levels, like tertiary consumers or apex predators

Question 3

homeostasis

Answer 3

maintaining the necessary physical conditions for survival; in balance; maintaining a constant state without any major, drastic changes

Question 4

endotherm

Answer 4

body temperature remains constant regardless of external environment; homeotherm

Question 5

ectotherm

Answer 5

body temperature = outside temperature; poikilotherm

Question 6

endothermy

Answer 6

endogenous heat production; the rate of metabolic heat > lost to environment

Question 7

ectothermy

Answer 7

external heat - reliant on environmental heat source to impact body temperature; rate of metabolic heat < lost to the environment (not enough heat is produced to stay warm)

Question 8

conformity vs regulation

Answer 8

conformity means you conform to the environment around you, while regulation allows cells to function independently of outside conditions

Question 9

conformity is

Answer 9

energetically inexpensive

Question 10

regulation is

Answer 10

energetically expensive

Question 11

metabolism

Answer 11

cost of life

Question 12

how does metabolic rate vary?

Answer 12

the time of day, eating, and environmental influences

Question 13

most common way to measure metabolism

Answer 13

oxygen consumption

Question 14

metabolic rate

Answer 14

rate of energy consumption; conversion of chemical energy to heat, external works, and growth

Question 15

what causes aerobic metabolic rates to increase?

Answer 15

temperature and exercise

Question 16

aerobic scope

Answer 16

the difference between the maximum (exercise induced) aerobic metabolic rate and the standard (resting) metabolic rate (being active vs sedentary)

Question 17

larger animals have

Answer 17

larger metabolic rates

Question 18

do endotherms have a higher or lower metabolic rate than ectotherms?

Answer 18

they have a higher metabolic rate than ectotherms because they require energy to maintain their internal temperature (costs 10x more energy)

Question 19

acute time scale

Answer 19

rapid, immediate response/effect w/ minimal biological interference

Question 20

what happens with acute responses?

Answer 20

the environment affects biological processes without physiology countering the physical effect of the environment

Question 21

aspects of acute response

Answer 21

Occurs at individual level, may involve behavioral changes
Typically not the result of changes in gene expression

Question 22

acclimation

Answer 22

chronic effects; with time (a few days or weeks), physiological processes modulate the effect of the environment, typically reducing environmental effects on physiology

Question 23

aspects of acclimation

Answer 23

Occur at the individual level and often involve changes in gene transcription

Question 24

evolution

Answer 24

organism can modify how the environment impacts its physiology through genetic changes that alter the proteins or their expression; requires changes over several to many generations

Question 25

aspects of evolution

Answer 25

Occurs at the population level and involves changes in genetic code Not reversible, as it gets encoded into the DNA

Question 26

TNZ

Answer 26

thermal neutral zone

Question 27

what is the TNZ?

Answer 27

set of ambient temperature where the cost of endotherm is constant

Question 28

what are 3 reasons that only 10% of energy is passed to upper trophic levels?

Answer 28

1. some energy is lost with the conversion to ATP 2. energy used to create body mass is lost to heat, maintenance, and work 3. not all prey in a trophic level is consumed

Question 29

what does the biological carbon pump do?

Answer 29

transports carbon from the atmosphere to the bottom of the ocean, where it is stored (ocean as major carbon sink)

Question 30

how does the carbon pump work?

Answer 30

4 major steps: 1. “Primed” by photosynthesis; phytoplankton fix CO2 2. Carbon used by zooplankton sinks into ocean 3. Much of the sinking carbon is reused by bacteria → consumed and recycled 4. Some of the carbon sinks to seabed, gets stored