Homeostatis

What does the human nervous system consist of?

CNS (brain and spinal cord)

PNS (peripheral nervous system / other nerves)

Homeostatis definition

Regulation of the internal conditions of a cell or organism to maintain optimum conditions for function in response to internal and external changes.

List three automatic control systems

Receptor - detect a stimulus

coordination centre - processes the information and co ordinated a response (brain, spinal cord, pancreas)

Effector - issues a response (contracting muscle or gland)

What are reflexes?

Automatic reactions carried out by the CNS to portect you from danger.

What are the steps to the reflex arc?

Stimuli - detect change in envirorment

Receptor - detect the change in the envirorment

(Sensory neurone)

Coordinator - processes the information

(Motor neurone)

Effector - causes a response

Response - protects you from danger

Reflex RP steps:

1. Person 1s places their dominant forearm on the table

2. Hold a ruler vertically between thumb and forefinger and drop without warning.

3. Person 1 catches as fast as they can

4. Reaction time is measured by the top of the thumb

5. Repeat and swap person 1 and two.

6. Calculate the mean and convert into reaction time.

How does the impulse pass through a synapse?

1. An electrical impulse will arive at a nuerone

2. This will cause the vesicles to release the chemical (neurotransmitter)

3. These chemicals bind to the next neurone and trigger a chemical impulse

What are all the hormones in the endocrine system and what do they produce

Pituitary gland - brain

thyroid gland - neck

Thyrus gland - thyroxide

Pancreas - insulin

adrenal gland - above kidney - adrenaline

Kidneys - vitimin D

Reproductive - oestrogen, testosterone

Pituitary gland