nervous and endocrine system

Cards (7)

  • nervous system: specialised network of cells that is our primary internal communication system - based on electrical and chemical signals
    main functions:
    • to collect, process and respond to information
    • to co-ordinate the work of different organs and cells
  • central nervous system: made up of brain and spinal chord
    • brain: centre of all conscious awareness - out layer (cerebral cortex) covers the brain like an orange peel
    highly developed in humans and is what distinguishes our mental functions
    • spinal chord: passes messages to and from the brain, connecting nerves to the PNS
    • also responsible for reflex actions - pulling hand away from a hot plate
  • peripheral nervous system: transmits messages through millions of neurons to and from the central nervous system
    • autonomic nervous system (ANS) : governs vital functions in the body - breathing, heart ratre
    • somatic nervous system (SNS): governs muscle movement and receives information from sensory receptors
  • endocrine system: controls vital functions in the body
    • thyroid gland: produces hormones that are secreted into the bloodstream and can affect any cell that has a receptor
    • thyroid gland produces thyroxine, affecting cells in the heart
    pituitary gland: 'master gland' as it controls the release of hormones from all other glands
    glands
    • adrenal
    • ovaries
    • testes
    • pancreas
  • endocrine and autonomic work together during a stressful event.
    during event:
    • hypothalamus activates pituitary gland to trigger activity in sympathetic branch
    • this then changes the parasympathetic state to the sympathetic state
  • adrenaline: stress hormone that is released into the bloodstream - triggers physiological changes in the body that create physiological arousal, ready for fight or flight
  • parasympathetic action: once the threat has passed, the nervous system returns the body to its resting state
    • parasympathetic system acts as a 'brake' and reduces the activities of the body that were increased due to the threat