The nervous system controls and coordinates all activities of the body. Here are some important points about the nervous system.
- Receives stimuli from sense organs and responds appropriately.
- Remembers previous experiences thus, allowing the organism to react better to the environment.
- Maintains homeostasis.
- Interacts with endocrine system to control and coordinate life processes.
Nervous control differs from hormone control in the following ways:
- It is very fast.
- Occurs through electrical impulses.
- Moves in one direction.
- The brain has nerve fibres or axons on the inside and this gives it a whitish appearance. Hence, we say that the brain has white matter inside and grey matter (the cell bodies or cyton) outside.
- Protected by cranium and vertebral column.
- Brain matter: There are two types of matter in the brain: grey matter outside and white matter inside. Grey matter is in the active portion of the brain and receives and stores impulses. Response to impulses originates here. Grey matter contains cell bodies while white matter is made of axons. White matter in the brain carries impulses to and from grey matter.
- The seat of thinking and actions based on thinking. 3 main regions: Forebrain, midbrain, and hindbrain.
The two major divisions of the nervous system are:
- Central Nervous System (CNS)
- Peripheral Nervous System (PNS)
Central Nervous System (CNS): The central nervous system comprises of the brain and the spinal cord.
Peripheral Nervous System(PNS): The peripheral nervous system comprises of nerves and grey matter.