Nervous and Endocrine Systems

• The nervous system - CNS


  CNS consists of all the neurones in the brain and spinal cord

  Coordinates complex functions

  A) CNS

  
• Central nervous system (CNS)


  • Consists of the brain and spinal cord

  • The brain has two hemispheres, and a highly-folder outer cerebral cortex, protected by the skull

  
• The nervous system - Peripheral NS & Somatic NS


  Peripheral NS - All the neurones leading to and from the brain

  Somatic NS - Transmits information about external stimulation from skin and muscles to the CNS, Controls voluntary movements
• Peripheral nervous system

  Autonomic NS - Involuntary control of homeostatic mechanisms

  • Runs to and from the internal organs regulating respiration, heart rate and digestion
  • Regulates the fight-or-flight response
• The nervous system - Peripheral NS - Autonomic NS


  Sympathetic NS - Operates when body’s activities increase (uses energy)

  • Prepares body for action(E.g. increases blood pressure, heart rate and ventilation rate)

  Parasympathetic NS - Operates when body’s activities decrease (restoring energy)

  • Returns the body to normal/rest (E.g. decreases blood pressure, heart rate and ventilation rate)
• The nervous system - Peripheral NS - Autonomic NS


  Sympathetic NS - Operates when body’s activities increase (uses energy)

  • Prepares body for action(E.g. increases blood pressure, heart rate and ventilation rate)

  Parasympathetic NS - Operates when body’s activities decrease (restoring energy)

  • Returns the body to normal/rest (E.g. decreases blood pressure, heart rate and ventilation rate)

  
• The endocrine system is a group of glands that produce and release hormones to regulate the body
• A gland is a tissue or organ which secretes (releases) hormones directly into the blood.

  These glands include:

  • Pituitary gland

  • Thyroid gland

  • Thymus

  • Adrenal glands

  • Pancreas

  • Ovaries (women)

  • Testes (men)

  
• The endocrine system

  • Uses hormones as signalling molecules

  • Hormones are transported around the body in the blood

  • Hormones are released by endocrine glands

  • They can be slow to take effect , but they have longer-lasting effects

  • Hormones act on target tissues by binding to specific receptors on the cell surface to trigger a response