Body Temperature Regulation

What is thermoregulation?

The control of internal body temperature.

What is the normal human core body temperature?

Approximately 37°C.

Why must body temperature be controlled?

To maintain optimum conditions for enzyme activity and cell functions.

Which part of the brain controls body temperature?

The thermoregulatory centre.

Where is the thermoregulatory centre located?

In the hypothalamus.

How does the thermoregulatory centre detect temperature changes?

It monitors blood temperature and receives information from skin temperature receptors.

What happens when body temperature rises above normal?

Responses increase energy transfer from the body to the surroundings.

What is vasodilation?

The widening of blood vessels near the skin surface.

How does vasodilation help cool the body?

More blood flows near the skin surface, increasing energy transfer to the surroundings.

What happens to sweat production when the body becomes too hot?

Sweat production increases.

How does sweating cool the body?

Sweat evaporates, transferring thermal energy from the skin to the surroundings.

Why is evaporation important for cooling?

Evaporation requires energy, which is transferred from the skin.

What happens when body temperature falls below normal?

Responses reduce energy loss and increase energy production.

What is vasoconstriction?

The narrowing of blood vessels near the skin surface.

How does vasoconstriction help conserve heat?

It reduces blood flow near the skin surface, reducing energy transfer to the surroundings.

What is shivering?

Rapid, involuntary muscle contractions that increase energy release through respiration.

How does shivering warm the body?

Increased muscle activity transfers more energy to thermal energy stores.

What happens to sweating when the body is too cold?

Sweating decreases or stops.

What happens to blood vessels near the skin when the body is too hot?

They dilate.

What happens to blood vessels near the skin when the body is too cold?

They constrict.

Why is temperature regulation an example of negative feedback?

Responses oppose the original temperature change, returning temperature towards normal.

Does vasodilation mean blood vessels move closer to the skin?

No, existing vessels widen, increasing blood flow near the surface.