Thermoregulatory System

Question 1

What is thermoregulation?

Answer 1

Maintaining a constant internal temperature independiente of external temperatures

Question 2

What are endotherms?

Answer 2

Animals that produce their own heat

Question 3

What are ectotherms

Answer 3

Animals that regulate heat from their surroundings

Question 4

What is homeostasis?

Answer 4

Any self regulating process that maintains a consistent internal environment.
E.g. body temperature
Blood pH
Blood glucose levels
Sodium, potassium and calcium concentrations

Question 5

How do ectotherms thermoregulate?

Answer 5

• external sources
• behaviours like basking
• regulating blood flow to conserve heat

Question 6

How do endotherms thermoregulate?

Answer 6

• metabolic heat
• behaviours like penguins huddling
• shivering (increasing metabolic heat production)
  -Panting
  -Insulation
  -Vasoconstriction/dilation
• counter-current heat exchange (like bird legs)

Question 7

What is panting?

Answer 7

• equivalente to when we sweat (wets skin so it evaporates and cools the body down)
• mammals don’t sweat so pant instead
• water evaporates from the tongue, mouth and throat

Question 8

How does insulation work?

Answer 8

• there is a fatty layer under the skin called the adipose
• fur traps air to keep warm and when it’s cold the hair stands on end to trap a larger layer (piloerection)

Question 9

What is vasoconstriction?

Answer 9

Blood vessels shrink to reduce blood flow which retains heat

Question 10

What is vasodilation?

Answer 10

Blood vessels widen to increase blood flow which loses heat through radiation

Question 11

Counter-current heat exchange

Answer 11

An artery runs beside a vein so heat is transferred via conduction. Blood is cooler when it reaches the feet so less heat is lost and the feet don’t freeze. There is also a shunt so blood can bypass the feet.