Temperature regulation

Page
1

Slide 1

Temperature Regulation

By the end of the lesson you should know

How the body corrects overheating

How the body corrects overcooling

What thermocreceptors do?

What volutary responses are carried out to control temperature

Slide 2

Slide 3

Slide 4

Why do we need to regulate: Internal body temperature

To provide the optimum conditions for enzyme-catalysed reactions to be carried out.

Slide 5

Body Temperature

Normal internal body temperature is 370C.

Temperatures above this:

denature enzymes and block metabolic pathways

Temperatures below this:

slow down metabolism and affect the brain.

Slide 6

Water Bath

Temperature set on thermostat

Too cool? Heater kicks on and temperature goes up

Too warm? Heater stays off until bath cools down

Constant checking and turning on and off

Slide 7

Control of homeostasis through feedback

Feedback system- cycle of events in which the status of a body condition is continually monitored, evaluated, changed, re-monitored, re-evaluated, etc.

Slide 8

3 basic components of a feedback system

1) receptor

sensor that responds to changes (stimuli)

2) control centre

sets range of values, evaluates input and sends output

3) effector

receives output from control centre and produces a response

Slide 9

Body Temperature Control

The hypothalamus acts as a thermostat and receives nerve impulses from heat and cold thermoreceptors in the skin.

There are also receptors in the hypothalamus- called central thermoreceptors.

These detect changes in blood temperature.

Slide 10

Vasoconstriction and Vasodilatation

Slide 11

Correction of overheating

Detected by thermoreceptors in the hypothalamus.

Causes vasodilation.

Sweating

Slide 12

Cooling down