Paper 2

• What is the nervous system?

  A specialised network of cells in the body
• What are the two main functions of the nervous system?

  To collect/process information and coordinate organs
• What are the two sub-systems of the nervous system?

  The central and peripheral nervous systems
• What does the central nervous system do?

  Passes messages to/from the brain and connects nerves
• What are the two main parts of the central nervous system?

  The brain and spinal cord
• What is the role of the brain?

  It is the center of all conscious awareness
• What distinguishes human brain functions from animals?

  The highly developed cerebral cortex
• What is the function of the spinal cord?

  Responsible for reflex actions
• What does the peripheral nervous system do?

  Transmits messages to/from the CNS
• What is the autonomic nervous system responsible for?

  Transmitting information to/from internal organs
• What are the two main divisions of the autonomic nervous system?

  The sympathetic and parasympathetic systems
• What functions does the autonomic nervous system govern?

  Breathing, heart rate, digestion, stress response
• What is the somatic nervous system responsible for?

  Transmitting sensory information and voluntary movements
• What is the difference between autonomic and somatic systems?

  Autonomic is involuntary; somatic is voluntary
• What is the role of the endocrine system?

  To regulate activity of cells and organs
• What do glands produce?

  Hormones
• How do hormones affect the body?

  They communicate chemical messages to organs
• What hormone does the thyroid gland produce?

  Thyroxine
• What is the function of adrenaline?

  Triggers the fight or flight response
• What does the adrenal gland produce?

  Adrenaline
• What does testosterone control?

  Development of male physical features
• What is the flight or fight response?

  Automatic response to perceived stress
• How does the autonomic nervous system control stress response?

  It triggers physiological changes for action
• What happens when a stressor is perceived?

  The hypothalamus activates the sympathetic branch
• What is the role of adrenaline in the body?

  Prepares the body for action
• What physiological changes does adrenaline trigger?

  Increases heart rate and respiration
• What are neurons?

  Nerve cells that transmit messages
• What is the function of the cell body in a neuron?

  Contains the nucleus and genetic material
• What do dendrites do?

  Carry nerve impulses towards the cell body
• What is the role of the axon?

  Carries impulses away from the cell body
• What does the myelin sheath do?

  Protects the axon and speeds up transmission
• What are nodes of Ranvier?

  Gaps that speed up impulse transmission
• What are terminal boutons?

  Make synaptic connections with other cells
• What are the three types of neurons?

  Sensory, relay, and motor neurons
• What do sensory neurons do?

  Carry messages from PNS to CNS
• What is the function of relay neurons?

  Connect sensory neurons to motor neurons
• What do motor neurons connect to?

  Connect CNS to effectors like muscles
• What happens when a neuron is in a resting state?

  The inside of the cell is negatively charged
• What occurs when a neuron fires?

  The electrical charge changes to positive
• What is synaptic transmission?

  Communication between neurons via chemical messages