Thermoregulation

Question 1

What is an endotherm

Answer 1

An animal that is able to maintain its internal temperature regardless of the external environment

Question 2

What is an ectotherm

Answer 2

An animal that is dependent on external sources of body heat

Question 3

What are the four physical processes of heat exchange

Answer 3

Radiation
Convection
Conduction
Evaporation

Question 4

What is conduction

Answer 4

• The transfer of heat by two objects that are in direct contact with one another. It occurs when skin comes in contact with a cold or warm object.

Question 5

What is convection

Answer 5

This is the transfer of heat to the air surrounding the skin.

Question 6

What is radiatiom

Answer 6

This is the transfer of heat via infra-red waves. This occurs between any two objects when their temperature differs.

Question 7

What is evaporation

Answer 7

This is the transfer of heat by the evaporation of water.

Question 8

What are some welfare implications of those four processes

Answer 8

Radiation- heat stress on animal, sunburn/ sunstroke
Evaporation- dehydration in animals/ dry skin
Conduction/ convection-mhard ground can cause lameness/ dogs could burn their feet on pavement

Question 9

Where is the thermoreguaktkry centre located and how does it operate

Answer 9

In hypothalamus
Monitors blood as it passes through the brain
There’s also skin receptors to detect external environment

Question 10

What mechanisms do endotherms use to respond to cold

Answer 10

Stamping of feet
Vasoconstriction of arterioles (less blood flow to skin surface)
Fur/ hair standing up
Shivering (muscle contraction generates heat)

Question 11

What mechanisms do endotherms use to respond to heat

Answer 11

Sweating
Vasodilation of arterioles
Slow/ reduced muscle activity
Panting

Question 12

What is a thermoneutral zone

Answer 12

A range of temperatures in the immediate environment that in which an animal can maintain a normal temperature without having to use excess energy about the normal basal metabolic rate

Question 13

What are upper and lower upper temperatures

Answer 13

Maximum/ minimum temperature an organism can withstand, otherwise cellular components may be damage/ reactions would be too slow to meet the animals needs

Question 14

What is the zone of thermal comfort

Answer 14

The temperature of an animal,al where they are most comfortable/ productive

Question 15

What is a thermal set point

Answer 15

Normal temperature +/- 0.5C

Question 16

Why might the use of a Bair Hugger be necessary

Answer 16

To keep patients warm during surgery, if blood loss/ anaesthesia effects it

Question 17

Why might cooling be used medically

Answer 17

Hyperthermia
To reduce brain damage/ necrosis of brain cells after stroke