Energy Budget

Question 1

What are the energy demands of organ- isms? (4)

Answer 1

Energy needed for maintenance growth, acitivity and reproduction

Question 2

What are factors effecting energy budget

Answer 2

Size of animals, (large size means more energy)
Activity(running takes more energy then walking)
Environment (cold environment means you need more energy to heat up)

Question 3

What are ectotherms

Answer 3

An animal that warms itself mainly by absorbing heat from its surroundings.

Question 4

What are endotherms

Answer 4

Actively regulate body temperature meaning they have a constant body temperature that they need to maintain
Endotherms need more energy then ectotherms

Question 5

Do bigger or smaller animals need more energy

Answer 5

Bigger animals need more energy but they use it more efficiently

Question 6

Scaling

Answer 6

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

Question 7

What is the ratio for surface area and length

Answer 7

Surface area is proportional to length squared

Question 8

What is the ration for volume and length

Answer 8

Volume is proportional to length cubed

Question 9

Where does surface area in organisms come from

Answer 9

membrane/ skin

Question 10

where does an organisms volume come from

Answer 10

Its mass

Question 11

Surface area to volume ration

Answer 11

Larger organisms have smaller SA/V ratio relative to smaller organisms

Question 12

Why do large organisms have large surface area

Answer 12

Large organisms have to maintain huge internal surface area to exchange matter/energy with the environment. Eg. humans have coils of intestine (humans need 25x surface area of the skin).

Question 13

Scaling of mass and surface area in mammals

Answer 13

As mass increases surface area increases

Question 14

How do organisms support their mass

Answer 14

Exchange matter and generate energy across the membranes (surface area)

Question 15

What are the disadvantages of small surface area

Answer 15

Nutrient exchange and energy generation

Question 16

What are the advantages of small surface area to volume ratio for organisms

Answer 16

Heat retention
Heat is produced by the entire volume and lost through surface area

Question 17

Allometry

Answer 17

Mass (M) effect on any aspect of biology (Y) is given by a power function

Question 18

What is the power function of allometry

Answer 18

Y=aM^b
a=valueofYperunitmass
b = scaling exponent
b=1 is isometric
b=0 Y is independent of M
b= any other value it is allometric

Question 19

What is log transfotmation

Answer 19

log Y = b(log X) + log a or y=mx+b
Log transformation can be used to make power
function linear.
The scaling component b becomes the slope (m)

Question 20

Isometry

Answer 20

b=1 in both log and power function
* Both dimensions remain proportional

Question 21

Positive Allometry (hyperallometry)

Answer 21

b is greater then 1 in both log and power function
As one dimension increases, the other dimension increases to a greater proportion

Question 22

Negative Allometry (hypometry)

Answer 22

b is less then 1 in both log and power function
As one dimension increases, the other dimension increases to a lesser proportion
example your head

Question 23

What is Energy ASSIMILATION

Answer 23

energy taken into the body

Question 24

What is resting metabolic rate

Answer 24

Energy required for survival

Question 25

What is the correlation with body size and energy in

Answer 25

Large organisms need more food so they get more Ein in a small amount of time
Large organism eat less often relative to body size
Large organisms have a lower breathing and heart rate since they take in more air and pump more blood

Question 26

Energy excretion

Answer 26

urine, feces, shedding, heat etc.

Question 27

Evolutionary fitness

Answer 27

The total amount and rate at which they obtain energy from food

Question 28

Retention time

Answer 28

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

Question 29

What is the process of EnergyEXCRETION

Answer 29

1. Food needs to be broken down (chewing, enzymes, etc) – this takes energy and represents a net loss of energy – hard to digest takes more E
2. Nutrients are then absorbed, which leads to a net gain of energy
3. When most energy has been absorbed, digestion rate decreases
4. Eventually, all possible energy is extracted, leaving undigestible “dregs” for excretion

Question 30

Does better quality food reduce retention time

Answer 30

Yes

Question 31

Rate of energy consumption

Answer 31

rate at which it converts chemical energy to heat and external work
Calories or joules

Question 32

Metabolic rate

Answer 32

calories per unit time
Helps determine how much food an animal needs
– Quantitative measurement of total activity of all physiological mechanisms
– Ecologically, helps to determine the pressure on energy supplies in the ecosystem

Question 33

Resting metabolic rate

Answer 33

Energy expenditure at rest but routine activities/day

Question 34

Basal metabolic rate

Answer 34

Metabolism at complete rest – lowest possible
Applies to homeotherms.
Is the animal’s metabolic rate
while it is
* In its thermoneutral zone * Fasting
* Resting

Question 35

Standard Metabolic Rate

Answer 35

Metabolic rate measured at a specified temperature (ectotherms)
– Is the animal’s metabolic rate while it is
* Fasting * Resting

Question 36

Field Metabolic Rate

Answer 36

Metabolic rate measured in wild animals

Question 37

How can we measure metabolic rate

Answer 37

Direct calorimetry - measures the rate at which heat leaves an animal’s body
Indirect calorimetry- cheap and easier

Question 38

What are the two methods of metabolic rate

Answer 38

Respirometry-Measuring an animal’s rate of respiratory gas exchange with its environment

the material-balance method– Measuring the chemical-energy content of the organic matter that enters and leaves an animal’s body

Question 39

Klebier’s law 3/4

Answer 39

b=3/4
Mass specific metabolic rate is proportional to mass to the 3/4
You use energy to heat yourself and lose heat through surface so the more heat you lose the bigger surface area. Volume on the other hand is how you make heat so more volume the more heat made. 3/4 the 4 comes from the fractal system that delivers energy (circulation system,) which is common to all animals

Question 40

Metabolic rate vs mass specific metabolic rate

Answer 40

Large organisms have large metabolic rate but small mass specific metabolic rate thus they use energy more efficiently

Question 40

Metabolic rate vs mass specific metabolic rate in large organisms

Answer 40

Large organisms have large metabolic rate but small mass specific metabolic rate thus they use energy more efficiently

Question 41

What is the relation between Absolute to Mass-Specific Relationships

Answer 41

M / W = a W ^(b-1)

Question 42

Energy activity

Answer 42

Any movement above resting
When activity increases the heat generated may cover the thermoregulation costs of a dormant (resting) organism.

Question 43

EnergyPRODUCTION

Answer 43

Eproduction represents both growth and reproduction
If an organism has a balanced energy budget, this value will be zero (in an adult)
If more than enough energy is consumed, the value is positive and mass will increase
If not enough energy is consumed, the value is negative and mass will decrease