The Nervous System

This lesson covers the structure and function of the human nervous system, including the roles of the central nervous system, peripheral nervous system, and different types of neurone. This is essential content for Edexcel GCSE Biology (1BI0) Topic 2: Cells and Control.

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Overview of the Nervous System

The nervous system allows organisms to detect changes in their environment and respond to them. It coordinates the body's activities rapidly using electrical impulses.

The nervous system can be divided into two main parts:

1. Central nervous system (CNS) — the brain and spinal cord.
2. Peripheral nervous system (PNS) — all the nerves that connect the CNS to the rest of the body, including sensory neurones and motor neurones.

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The Pathway of a Nervous Response

When the body detects a change in the environment, the following pathway is followed:

Stimulus → Receptor → Sensory neurone → CNS (coordinator) → Motor neurone → Effector → Response

Let us break this down: