The Central Nervous System
Consists of the brain and the spinal cord. Controls much of our behaviour by passing electrical impulses around the body through nerve fibres made up of tracts of neurones.
A neurone is a tiny nerve cell that communicates messages in the brain and around the rest of the body. This happens through impulses passed around the nervous system via synapses.
A synapse is a junction between two neurones where messages are passed from one neuron to another. They are passed through neurotransmitters which move from the terminal button of one neurone to the receptors on the other neurone's dendrite.
These are chemicals which are released by neurones into synapses. Receptors (protein molecules on the membrane of th neurone) on adjacent neurones let the neurotransmitter attach to them. The neurotransmitter must be the same shape as the receptor. This changes the chemical make-up of the neurone and therefore its voltage, causing an electrical charge to pass down it's axon. When it gets to the terminal buttons at the end of that neurone, it starts again.
A hormone is a chemical that gets released from a gland. It travels in the blood and affects target organs such as muscles, sex organs and other glands. E.G. Oestrogen and Testosterone. Oestrogen is produced in the ovaries of sexually mature women and testosterone produced in the testes. Either sex produces a little of both. They are responsible for changes at puberty and menstruation.
The uneven distribution of tasks to either side of the brain. Any function carried out by one side of the brain is called a lateralised function (e.g language).
The brain has two hemispheres and either is responsible for different tasks. It differs between males and females.
Men - more left hemisphere activity during linguistic tasks.
Women - bilateral activity during the same tasks.
Men - high levels of activity in right hemisphere during spatial tasks.
Women - again, bilateral.
The corpus callosum (connecting tissue between hemispheres) is seen to be thicker in females, therefore people conclude that this explains the bilateralization - more efficient communication.
Units of information we inherit from our parents on a physiological level. They contol or influence characteristics we have such as our predisposition to mental disorders, personality and sexual development.
They are sections of strands of a chemical called DNA we find in our cells.