1st Diagram
- example is a motor nerve. The orange part would be embedded in the spine and at the other end, it would connected to the effector (most likely a muscle)
- the electrical impulse (or the nerve impulse) is carried a long inside the nerve down the orange structure from the cell body to the end known as the synoptic knob where it connects to the muscle.
- this can be up to a metre long. A single cell is shown in orange.
- the long structure is known as the axon.
- in mammals, the axon is surrounded by the Schwann cell - contains a great deal of fat and form a Myelin Sheath.
- this is one way of linking our co-ordinator to our effector
2nd Diagram
- the endocrine system
- involves the endocrine gland that produces a chemical known as a hormone (they can be proteins or steroids). example of this is Adrenal gland
- the hormone is secreted into the blood. Adrenaline is secreted by the Adrenal gland into the blood and travels to the target tissue (or target organ) and then it will have an effect.
- hormones can have multiple targets and bring about multiple effects contrasting with the nerve system.
e.g. the nerve impulses are fast
hormones are relatively slow
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