Temperature 1 Flashcards
1
Q
how does thermal energy affect animals (2)
A
- influences chemical interactions that affect macromolecular structure and biochemical reactions
- affect shape and function of all proteins, including enzymes
2
Q
what equation is used to describe the effects of thermal energy on animal functions
A
- Van’t Hoff equation
3
Q
Van’t Hoff equation (2)
A
- Q10 = (k2/k1)^10/(t2-t1)
4
Q
Van’t Hoff equation: k2 and k1
A
- rates of the reaction at two different temperatures
5
Q
Van’t Hoff equation: t2 and t1
A
- two different temperatures
6
Q
Van’t Hoff equation: simplified (2)
A
- for exactly 10 C change
- Q10 = k2/k1
7
Q
what are the Q10 values for more chemical reactions (metabolism, growth, locomotion) (2)
A
- 2-3
- reaction doubles or triples with a 10 C change in temperature
8
Q
what are the Q10 values for a purely physical process (diffusion) (2)
A
- closer to 1.0
- temperature effects are more minimal
9
Q
what is temperature often referred to
A
- ecological master factor
10
Q
thermal strategy
A
- combination of behavioral, biochemical, and physiological responses that ensure body temperature is within an acceptable limit
11
Q
ambient temperature (2)
A
- temperature of the animal’s surroundings
- most important environmental influence on the animal’s thermal strategy
12
Q
what thermal factors must animals be able to survive (2)
A
- thermal extremes
- thermal changes over days, seasons, etc
13
Q
what kind of temperature changes do ecosystems experience (2)
A
- spatial variation in temperature
- temporal variation in temperature
14
Q
what are the ranges of temperatures in terrestrial life
A
- 60 C to +60 C
15
Q
what are the ranges of temperatures in aquatic life
A
- 2 C to +40 C
16
Q
why do fish have poor freezing temperature tolerance
A
- fish cannot survive in ice, so there is no selection for freezing temperature tolerance
17
Q
what are the two major thermal strategies (2)
A
- tolerance
- regulation
18
Q
thermal strategy: tolerance
A
- body temperature is allowed to vary with ambient temperature
19
Q
thermal strategy: regulation
A
- body temperature does not vary with ambient temperatures
20
Q
what is body temperature a reflection of
A
- the thermal energy of the molecules in the body
21
Q
describe the movement of thermal energy/heat fluxes (3)
A
- can move between animals and the environment
- thermal energy moves “down” a temperature gradient
- many sources and sinks of thermal energy
22
Q
what types of thermal energy contribute to total thermal energy (5)
A
- metabolism
- conduction
- convection
- radiation
- evaporation
23
Q
conduction
A
- transfer of thermal energy from one object or fluid to another
24
Q
heat flux symbol
A
Q
25
heat flux
- rate of transfer from warm to cold
26
heat flux equation name
- Fourier's law
27
Fourier's law
Q = λ * ΔT / L
28
Fourier's Law: λ
- thermal conductivity
29
Fourier's Law: ΔT
- temperature gradient
30
Fourier's Law: L
- distance over which the gradient extends
31
heat transfer mechanisms (4)
- conduction
- radiation
- convection
- evaporation
32
heat transfer mechanisms: conduction (2)
- gain or loss to the environment
- transfer by **direct contact**
33
heat transfer mechanisms: radiation (2)
- gain or loss to the environment
- transfer by means of **electromagnetic radiation**
34
heat transfer mechanisms: convection
- gain or loss to the environment
- transfer to a **moving medium**
35
what are examples a moving medium during convection (2)
- breathing air or water
- wind chill
36
heat transfer mechanisms: evaporation
- heat loss to the environment
- transfer as a result of the **latent heat of evaporation**
37
what are examples of the latent heat of evaporation (3)
- sweating
- breathing
- drying
38
why does sweating help to cool us down (2)
- converting water from liquid to vapor uses energy
- by covering body with water, it will evaporate and use energy to cool us down
39
what aspects of our anatomy can change the rate of heat exchange (2)
- surface area
- surface insulation
40
which organs are better at transferring heat (2)
- respiratory organs
- high surface area and low surface insulation
41
what is the role of behaviour in heat transfer mechanisms
- behaviour can alter rates of heat exchange
42
what are the major determinants of heat exchange via conduction (2)
- thermal conductivity
- heat capacitance
43
thermal conductivity
- ability of heat energy to move within material
44
how are thermal conductivity and insulation related
- high conductivity = poor insulation
45
heat capacitance
- ability to store heat energy
46
what is the heat capacitance in water vs air (2)
- water can store 3000x more heat than air
- water is considered a heat sink
47
what do thermal conductivity and heat capacitance influence (3)
- life in water vs air
- insulation materials
- behaviour
48
how does the SA:V ratio affect heat exchange
- high ratio increases rates of heat exchange
49
compare the rates of heat exchange between large and small animals
- large animals exchange heat more slowly than small animals
50
Bergmann's rule
- mammals and birds living in cold environments tend to be larger
51
Allen's rule
- mammals and birds in colder climates have smaller extremities
52
what behaviours can affect SA:V ratio
- body posture
- huddling behaviour
53
how does body posture affect heat exchange
- can alter the exposed surface area
54
how does huddling behaviour affect heat exchange
- reduces effective surface area for heat exchange
55
insulation
- layer of material that reduces thermal exchange
56
internal insulation
- insulation under the skin
57
internal insulation: example
- blubber
58
external insulation
- insulation on the body surface
59
external insulation: examples (4)
- hair
- feathers
- air
- water
60
what determines the effectiveness of insulation
- depends on the thickness
61
what terms are used to describe the relative stability of body temperature (2)
- piokilotherm
- homeotherm
62
poikilotherm
- variable body temperature
63
homeotherm
- stably body temperature
64
what are terms to describe the sources of thermal energy in animals (2)
- ectotherm
- endotherm
65
ectotherm
- environment determines body temperature
66
endotherm
- animal generates internal heat to maintain body temperature
67
what animals are commonly classified as endothermic, homeotherms (2)
- mammals
- birds
68
what animals are commonly classified as ectothermic poikilotherms (4)
- amphibians
- reptiles
- fish
- invertebrates
69
what animals are homeothermic ectotherms
- environment determines body temperature, but the environmental temperature is very constant
70
what animals are endothermic poikilotherms
- animals that experience a range of temperatures as they use their endothermy for specific situations (before flight, etc)
