nervous system

• What is the primary function of the nervous system?

  It allows you to react to your environment.
• What are the main components of the central nervous system (CNS)?

  • Brain
  • Spinal cord
• What are neurones?

  Nerve cells that make up the nervous system.
• What do sensory receptors do?

  They detect changes in the environment.
• What type of stimuli do receptors in the eyes detect?

  Light.
• What type of stimuli do receptors in the skin detect?

  Touch (pressure) and temperature changes.
• How is information sent to the central nervous system?

  As nervous (electrical) impulses along sensory neurones.
• What does the CNS consist of?

  The brain and spinal cord.
• What does the CNS send information to?

  An effector (muscle or gland).
• What is the role of the CNS in response coordination?

  It decides how to respond to a stimulus and instructs an effector.
• What happens when the CNS sends information to an effector?

  The effector responds accordingly, such as a muscle contracting or a gland secreting a hormone.
• How are electrical impulses transmitted in a neurone?

  Along the axon of the neurone.
• What are dendrites in neurones?

  Branched endings that connect with other neurones.
• What is the function of the myelin sheath?

  It acts as insulation for some axons.