Homeostasis

Week 2 – Homeostasis (03.10.2022)


Requirements of being and staying alive:
 Water (70%)
 Food
 Oxygen
 Heat
 Pressure

Homeostasis:
 Regulation and maintenance of a constant environment in the body.
 Provides a stable environment for the cells of the body.
 Minimises disturbances to the internal environment.
 Organisms have feedback control for comfort and survival.

Control Systems in the body:
 Sensors/Receptors – Gathers data and detects changes.
 Control Centre – Receives data, sends messages.
 Communication Systems – Delivers messages in form of nerve impulses and hormones
to target organs.
 Targets – Organ, tissue or cell that responds to change.

Homeotherms:
 Animals that maintain a relatively constant body temperature.

Body Temperature:
 45 - Death
 37 – Body Temperature
 34 – Slower Metabolism

Thermal Production:
 Voluntary: Exercise
 Involuntary: Shivering

Hypothalamus:
 Anterior Hypothalamus
 Sweating
 Increase of skin blood flow
 Decrease heat loss
 Decrease skin blood flow

The Thermogenic Effect of Hormones and Exercise:
 Catecholamines are increased during exercise

Heat and Cold Acclimatization:
 Heat Acclimatization
o Increase plasma volume
o Earlier onset of sweating
o Higher sweat rare