The Nervous System

    Cards (20)

    • How is a nerve cell adapted for its function?
      • Function: carry electrical impulses
      • Adaptations: Long, thin, lots of branched connections to either end (dendrites) which allows them to pass messages to other nerve cells
    • What is needed for a nerve cell to communicate with another?
      Synapse
    • What is a synapse?
      • Connection between nerve cells
      • When an electrical signal reaches the end of a nerve, it releases chemicals that cross the gap to the next nerve cell.
      • These chemicals trigger a new signal, which continues through the next nerve, repeating the process.
    • What is the central nervous system and what does it do?
      • brain and spinal cord.
      • It controls and coordinates the body's responses by processing information from the senses and sending instructions to muscles and organs.
      • It acts as the body's control centre, regulating movement, thoughts, and vital functions like breathing and heartbeat
    • What is the nervous system?
      • The nervous system controls the body's responses.
      • It includes the central nervous system (CNS) (brain and spinal cord) and the peripheral nervous system (PNS) (nerves).
      • It detects changes, processes information, and sends signals to muscles and organs
    • What passes along nerve cells?
      Electrical impulses.
    • What is the gap between two neurones called?
      Synapse
    • What is released across a synapse?
      Chemicals
    • What is the role of a receptor?
      To detect a stimulus.
    • What is the role of a sensory neurone?
      To transfer a signal from a receptor to the CNS (central nervous system)
    • What is the role of a motor neurone?
      To transfer a signal from the CNS to an effector
    • What is the role of a relay neurone?
      To transmit a signal from a sensory neurone to a motor neurone
    • What is a reflex?
      An automatic response to a stimulus
    • Pathway of a reflex arc:
      stimulus➔ receptor ➔ sensory neurone  ➔ relay neurone  ➔ motor neurone  ➔ effector  ➔ response
    • Examples of reflexes:
      • sneezing
      • blinking when you get dust in your eye
      • moving your hand away from a hot object
    • Why are reflexes important?
      Protect us from harm
    • The diagram below shows part of a reflex arc. Which structure is being indicated?
      Receptor
    • The diagram above shows part of a reflex arc. Which structure is being indicated?
      Sensory neurone
    • The diagram above shows part of a reflex arc. Which structure is being indicated?
      Relay neurone
    • The diagram above shows part of a reflex arc. Which structure is being indicated?
      Effector