The Nervous System
Biology: Cambridge International GCSE Supplement, topic 14.1.1
The Human Nervous System
The role of the nervous system is to protect an organism from harm by responding to changes in the internal and external environment. It does this by coordinating communication between different parts of a multicellular organism. The nervous system is made up of:
The brain
- The brain is one of the components (parts) of the central nervous system (CNS).
- The CNS coordinates the response of effectors.
- Effectors are muscles or glands that act in response to a change in the internal or external environment.
The spinal cord
- The spinal cord is the other component (part) of the CNS. It is also important in coordinating the response of effectors to changes in the environment.
The neurones (nerve cells)
- Neurones (nerve cells) carry electrical impulses (signals) between receptors, the central nervous system (CNS) and effectors.
- Neurones make up the peripheral nervous system.
Test yourself on The Nervous System
Which of the following is NOT a component of the human nervous system?