How the Nervous System Works Revision Notes | GCSE OCR Foundation Biology

What this lesson covers

Explore the structure and function of the nervous system, including how it coordinates responses to stimuli and the pathway from stimulus to response.

• Explain how the structure of the nervous system is adapted to its functions
• Describe the pathway of information from stimulus to response
• Identify the components of the central nervous system and their roles
• Apply the stimulus-response pathway to real-life examples

Key ideas to keep in view

Use this lesson to stay inside B3.1 Coordination and control - the nervous system while connecting the detail back to the wider B3: Organism level systems topic.

• B3: Organism level systems
• B3.1 Coordination and control - the nervous system
• GCSE OCR Foundation Biology

Lesson notes preview

Read the core explanations from How the Nervous System Works before testing yourself from memory.

• 1. Why Your Body Needs a Control System
• Right now, your nervous system is working overtime. It's processing these words, controlling your breathing, and keeping you balanced in your chair. Without it, you'd be unable to react to anything — no pulling your hand away from a hot surface, no catching a falling object.
• The nervous system is your body's electrical wiring and control centre. It detects changes in your environment and coordinates responses faster than you can think. This coordination keeps you alive and helps you interact with the world around you.
• Picture the nervous system as a motorway network. Information travels along nerve cells called neurones like cars on roads. These electrical impulses carry messages at incredible speeds — up to 120 metres per second.
• A nerve cell that carries electrical impulses around the body. Transmits information between receptors, CNS, and effectors.
• Neurones are perfectly adapted for their job. They're long and thin to carry impulses over large distances. They have branched endings to connect with other neurones, creating a network that reaches every part of your body.
• Trap: Many students think nerve impulses are like water flowing through pipes. Actually, they're electrical signals that jump from one neurone to the next, maintaining their strength throughout the journey.
• At the heart of your nervous system sits the Central Nervous System (CNS). This is your body's mission control — the brain and spinal cord working together to process information and coordinate responses.
• The brain and spinal cord that coordinate responses to stimuli. Controls all body functions and processes information from receptors.
• The brain is the ultimate processor, handling complex decisions and storing memories. The spinal cord acts like a superhighway, carrying messages between the brain and the rest of your body. Together, they make sense of incoming information and decide what to do about it.

Continue through the topic

Move to the related lessons or back to the topic page when you need the wider sequence before exam-style practice.