NERVOUS SYSTEM (HOMEOSTASIS)

• Homeostasis


  The regulation of the internal conditions of a cell or organism to maintain optimum conditions for function in response to internal and external changes
• Things homeostasis controls in the human body

  • Blood glucose concentration
  • Body temperature
  • Water levels
• Components of control systems

  • Receptors that detect stimuli
  • Coordination centres that receive and process information
  • Effectors that bring about responses to restore optimum levels
• Nervous system


  Enables humans to react to their surroundings and to coordinate their behaviour
• Information from receptors passes along cells (neurones) as electrical impulses to the central nervous system (CNS)


  CNS coordinates the response of effectors which may be muscles contracting or glands secreting hormones
• Reflex arc


  Includes the sensory neurone, synapse, relay neurone and motor neurone, enabling automatic and rapid reflex actions
• Students should be able to extract and interpret data from graphs, charts and tables, about the functioning of the nervous system
• Students should be able to translate information about reaction times between numerical and graphical forms
• Required practical activity 7: plan and carry out an investigation into the effect of a factor on human reaction time


  1. AT 1, 3 and 4 skills covered

  2. Provides opportunities to develop WS and MS
• Cerebral cortex, cerebellum and medulla


  Different regions of the brain that carry out different functions
• (HT only) Neuroscientists have been able to map the regions of the brain to particular functions by studying patients with brain damage, electrically stimulating different parts of the brain and using MRI scanning techniques. The complexity and delicacy of the brain makes investigating and treating brain disorders very difficult
• (HT only) Evaluate the benefits and risks of procedures carried out on the brain and nervous system