Topic 7: Energy Budgets

Question 1

Energy Demands

Answer 1

reproduction, growth, maintenance, activity

Question 2

Energy Budgets depend on:

Answer 2

size, activity, environment

Question 3

Size/Mass effects the way organisms:

Answer 3

• move
• how often they eat
• what they eat

Question 4

Scaling

Answer 4

study of the effect of size/mass on anatomy/physiology

Question 5

SA=

Answer 5

l^2

Question 6

V=

Answer 6

l^3

Question 7

Increase in size causes a _______ in SA/V

Answer 7

decrease

Question 8

Advantage of low SA/V in large organisms

Answer 8

heat retention;
heat produced by entire volume & lost through SA

Question 9

Disadvantage of low SA/V in large organisms

Answer 9

nutrient exchange & energy generation; bigger organisms have highly branched circulatory, digestive, and respiratory systems to increase SA

Question 10

M=

Scaling Relationships Equation

Answer 10

aW^b

Question 11

logM=

Answer 11

loga + blogW

Question 12

Log transformation is used for:

Answer 12

data normalization & to make a power function linear

Question 13

Allometry

Answer 13

both dimensions do not vary proportionally to size

Y=aM^b

Question 14

Isometry

Answer 14

both dimensions remain proportional

Y=aX’
logY = loga + (1)logX

Question 15

Hyperallometry (Positive allometry)

Answer 15

as one dimension increases, the other increases to a greater proportion

Question 16

Hypoallometry (Negative allometry)

Answer 16

as one dimension increases, the other increases to a lesser proportion

Question 17

E in =

Answer 17

E rmr + E activity + E production + E excretion

Question 18

E production =

Answer 18

E growth + E reproduction

Question 19

E assimilation =

Answer 19

E rmr + E activity + E production

or

E in - E excretion

Question 20

larger animals have a ____ Ein/unit time because:

Relationship between body size and E in

Answer 20

greater;

• eat less often but more at once
• take in more air w/ each breath and pump more blood per heartbeat but have a low breathing rate and heart rate compared to smaller animals

Question 21

E excretion

Answer 21

feces, urine, shedding, heat

how long food remains in digestive tract is a phenotypic trait that responds to pressures in the environment

Question 22

Measure of Evolutionary Fitness

Answer 22

total amount of rate @ which organisms obtain energy from food

Question 23

Greater retention time =

Answer 23

greater time taken to digest food

Question 24

High quality food

Answer 24

• easy to digest
• less E lost
• high rate
• plateau’s sooner and higher

Question 25

Low quality food

Answer 25

harder to digest, more E lost, low rate, plateau’s later and lower

Question 26

Metabolic Rate

Answer 26

rate of energy consumption when it converts chemical energy to heat & external work

Question 27

3 reasons for metabolic rate

Answer 27

• helps determine how much food needed
• quantitative measurement of total activity
• ecologically helps determine the pressure on energy supplies in the ecosystem

Question 28

E rmr

Answer 28

resting metabolic rate - energy expenditure at rest but routine activities/day

Question 29

E bmr

Answer 29

Basal metabolic rate = metabolism at complete rest

• applies to endotherms

Question 30

E smr

Answer 30

Standard metabolic rate = metabolic rate measured at a specific temperature

• applies more to ectotherms

Question 31

E fmr

Answer 31

Field metabolic rate = metabolic rate measured in wild animals

Question 32

E rmr can be measured through: (2)

Answer 32

Direct or indirect calorimetry

Question 33

Direct Calorimetry

Answer 33

heat loss - usually an expensive and cumbersome process

Question 34

Indirect Calorimetry

Answer 34

O2 consumed or CO2 produced - usually the cheaper and easier process

• respirometry
• material balance method

Question 35

Respirometry

Answer 35

rate of respiratory gas exchange with the environment

Question 36

Material-balance method

Answer 36

measuring chemical content of organic matter that enters and leaves body

Question 37

Relation between weight-specific RMR and Body Weight: (equation)

Answer 37

weight-specific MR decreases as body weight increases

M/W = aW^(b-1)

(b-1) = always negative!

Question 38

E activity

Answer 38

includes most forms of movement above the resting rate

• when the activity increases the heat generated may cover the thermoregulation costs of an energy budget

Question 39

E production

Answer 39

represents growth & reproduction

Question 40

What is the E production when the energy budget is balanced?

Answer 40

0

Question 41

more than enough energy is consumed, E production is:

Answer 41

positive and mass increases

Question 42

if not enough energy is consumed, E production is:

Answer 42

negative and mass decreases

Question 43

smaller animals have ______ per gram BMR than larger animals (for endotherms & ectotherms)

Answer 43

greater

Question 44

______ active animals have __________ metabolic rate

Answer 44

more; higher