Notes on Coordination and Response in Humans

Chapter 12: Coordination and Response in Humans

Main Components of the Nervous System

  • Sensory Receptors

    • External: Detect environmental stimuli (e.g. light, sound).

    • Internal: Monitor internal conditions (e.g. temperature, pain).

  • Integration Centre

    • Brain: Processes sensory information and coordinates responses.

    • Spinal Cord: Acts as a relay between sensory and motor pathways.

Types of Neurones

  1. Sensory Neurones

    • Transmit sensory information from receptors to the integration centre.

  2. Relay Neurones

    • Connect sensory and motor neurones and are located in the spinal cord and brain.

  3. Motor Neurones

    • Carry signals from the integration centre to effector organs (muscles and glands).

Parts of a Neurone

  • Dendrites

    • Receive information (incoming signals).

  • Cell Body

    • Contains the nucleus and organelles.

  • Axon

    • Transmits nerve impulses away from the cell body.

  • Myelin Sheath

    • Insulates the axon and speeds up nerve impulse transmission.

Brain and Spinal Cord Structure

  • Brain Regions:

    • Hypothalamus: Regulates body temperature and hunger.

    • Pituitary Gland: Known as the 'master gland'; controls other endocrine glands.

    • Medulla Oblongata: Controls vital functions like breathing and heart rate.

  • Spinal Cord Structure:

    • Comprised of:

    • White Matter: Contains myelinated axons, responsible for message transmission.

    • Grey Matter: Contains neuronal cell bodies, involved in processing information.

Spinal Nerves

  • Each spinal nerve has two roots connecting to the spinal cord:

    1. Dorsal Root

    • Contains sensory axons; transmits nerve impulses from sensory receptors to the integration centre.

    1. Ventral Root

    • Contains motor axons; transmits nerve impulses away from the integration centre to muscles or glands.