Test

• Nervous system


  Body's internal communication system, maintains many of our internal physiological processes
• Nervous system breakdown


  • Central Nervous System [CNS]
  • Peripheral Nervous System [PNS]
• Central Nervous System [CNS]


  • Brain = control centre, makes decisions
  • Spinal cord
• Peripheral Nervous System [PNS]


  • Entire network of nerve cells [neurons] which send messages through your body
• PNS parts


  • Somatic NS [SNS]
  • Autonomic NS [ANS]
• Somatic NS [SNS]


  • Voluntary - things you can control, e.g., movement
• Autonomic NS [ANS]


  • Automatic = involuntary = you cannot control it, e.g., breathing, sweating, heart rate, digesting food
• ANS branches


  • Parasympathetic division
  • Sympathetic division
• Parasympathetic division


  • Normal resting state [rest and digest]
• Sympathetic division


  • Fight or flight mode, activated if you detect a threat
• Adrenaline is released during the fight or flight response
• Adrenaline gives you energy to fight or run away [flight]
• Physiological changes during sympathetic division

  • Heart rate increases
  • Digestion is inhibited
  • Respiration increases
  • Pupils dilate
• When the threat has gone away

  Parasympathetic division takes over and brings the body back to normal resting state
• At one time, only one of these branches can be active
• Neuron


  Nerve cell
• Electrical impulses travel along neurons allowing communication
• Types of neurons


  • Sensory neuron
  • Relay neuron
  • Motor neuron
• Sensory neuron


  • Sends messages from the senses to the central nervous system
• Relay neuron


  • Found within the central nervous system, middle men, send messages within the central nervous system
• Motor neuron


  • Sends messages from the central nervous system to the muscle [to tell the muscle to move]
• Synapse


  Gap between 2 neurons
• Synaptic transmission


  Uses neurotransmitters to send a message over the gap [synapse]
• Neurotransmitter


  Chemical messenger in brain
• Pre synaptic neuron


  • The neuron before the synapse, sends the message across the synapse
• Vesicle


  • Sack containing the neurotransmitter [chemical]
• Vesicle opens and releases the neurotransmitter into the synapse
• Neurotransmitter goes across the synapse and binds to receptor sites on the post synaptic neuron
• Each neurotransmitter can only bind to a certain receptor site
• Post synaptic neuron


  • The neuron after the synapse, receives the message
• Endocrine system


  System of glands and hormones
• Hormone


  Chemical messenger which travels in bloodstream, needed to keep many of our vital physiological processes functioning
• Gland


  • Secrete hormones
• Hormones


  • Testosterone
  • Oestrogen
  • Adrenaline
  • Insulin
  • Melatonin
• Testosterone


  • Male sex hormone [testes]
• Oestrogen


  • Female sex hormone [ovaries]
• Adrenaline


  • Released during the fight or flight response, gives you energy to fight or run away [adrenal glands = on top of kidneys]
• Insulin


  • Regulates level of blood sugar [pancreas]
• Melatonin


  • Regulates sleep-wake cycle [pineal gland]
• Pituitary gland


  • Master gland, controls all other glands