Homeostasis - Module 5 Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

Define homeostasis

A

The maintenance of a stable equilibrium of conditions inside the body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is a negative feedback system? give an example

A

When a system acts to reverse a change back to ideal conditions
E.g blood glucose levels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is a positive feedback system? Give an example

A

When a system acts to reinforce a change and increase a response
E.g blood clotting

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is thermoregulation?

A

Maintenance of stable core body temperature to maintain optimum enzyme activity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What 5 factors control thermoregulation?

A
  1. Exothermic chemical reactions
  2. Convection
  3. Radiation
  4. Latent heat of evaporation
  5. Conduction
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How do ectotherms control internal temperature?

A

Using their environment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Why don’t ectotherms living in water need to thermoregulate?

A

High specific heat capacity of water means temperature remains constant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Name 3 behavioural responses of ectotherms to increase body temperature, how do these change to decrease body temperature?

A
  1. Basking in sun
  2. Orientation to maximise surface area in the sun
  3. Pressing bodies against the ground

To decrease body temperature, reverse!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Describe 2 physiological responses of ectotherms to regulate body temeprature

A
  1. Colour - in colder environments dark colours to absorb heat vice versa with light colours in warm environments
  2. Alter heart rate to change metabolism
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Who has the higher metabolism; endotherms or ectotherms?

A

Endotherms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How do endotherms detect a change in temperature?

A
  1. Peripheral receptors in skin detect surface temperature
  2. Hypothalamus detects changing blood temperature
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Describe 5 behavioural responses from endotherms to maintain temeprature

A
  1. Burrowing
  2. Basking in sun
  3. Pressing against surfaces
  4. Hibernation
  5. Wallowing in water
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Describe behavioural responses specifically of humans to maintain body temeprature

A
  1. Clothing
  2. Houses
  3. Heating sources
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Describe the physiological mechanisms endotherms use to cool down

A
  1. Vasodilation
  2. Sweating/ dogs panting, this is evaporation
  3. Hairs lie flat, this reduces the insulation effect of body hair
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is vasodilation?

A

When arterioles dilate forcing blood into capillaries close to the surface of the skin to release heat by radiation
Opposite occurs for vasoconstriction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Describe the physiological responses of endotherms to warm up

A
  1. Vasoconstriction
  2. Decreased sweating
  3. Hairs raise - to induce insulating effect
  4. Shivering
17
Q

What are 3 anatomical adaptations endotherms in cold environments have?

A
  1. Blubber
  2. Minimal SA:V ration
  3. Hibernation and making fat stores
18
Q

How is thermoregulation controlled in endotherms?

A

Using negative feedback systems in the hypothalamus
- heat loss centre
- heat gain centre