Nervous sytem

• Responds to stimuli

  Irritability
• Transmits action portential over long distance (Characteristic of nervous system)

  Conduction
• Can analyse and interpret information (Characteristics of nervous system)

  Intergration
• 2 main parts of nervous system

  Central nervous system

  Peripheral nervous system
• The specialised tissue that forms the nervous system, composed of neuron and glial cells

  Nervous tissue
• What are the 2 main type of cells in the nervous tissue

  Neurons and Glial cells
• A specialised nerve cell that transmits electrical and chemical signal in the nervous system

  Neuron
• 3 main parts of a neuron

  Cell body

  Dendrites

  Axon
• A supporting cell in nervous tissue that maintains and protects neurons

  Glial cell
• Primary function of a glial cell

  Support and protect neurons
• The part of the nervous system consisting of the brain and spinal cord

  Central nervous system
• The network of nerves running to and from the brain and spinal cord to the rest of the body

  Peripheral nervous sytem
• What 2 typew of nerves make up PNS system

  Cranial nerves and spinal nerves
• Fibers that make up cranial and spinal nerves

  Nerve axon
• what are the 2 types found in any peripheral nerve

  Sensory (afferent) and motor (efferent) axons
• Nerve fibers that transmit action potentials from the body's periphery to the central nervous system

  afferent axons
• Which direction do signals travel in afferent axons?

  From Periphery to CNS
• Nerve fibers that transmit action potentials from the central nervous system to the body's periphery

  Efferent axons
• Electrical signal that propagates along nerve axons to transmit information

  Action potential
• What is the function of action potential in motor axon

  To activate muscle
• What two types of additional information must these axons encode?

  Type and location of sensation
• How do sensory axons achieve specificity for different stimuli

  Through specialised nerve endings
• Specialised nerve ending that responds to a specific type of stimulus

  Sensory receptor
• True or False; Not all skin areas have the same number of sensory receptors

  True
• Sensory receptors are connected to sensory nerve fibers
• The area of skin supplied by a single sensory neuron is called a receptive field
• Each receptive field may contain many receptor
• Each sensory neuron will give information about a specific area of the body surface
• The ability to determine the location and nature of a particular sensation

  Sensory localisation
• What are the 3 factors to determine the ability to localise sensations?

  Number of receptors

  Sensitivity of receptors

  Size and arrangement of receptive fields
• The decrease in action potential frequency over time in response to constant, non harmful stimuli

  Sensory adaptation
• what are the 3 sensory modalities show adaptation over time

  touch smell temperature
• Fill up

  A) Dendrites

  B) nucleus

  C) axon

  D) schwann cell

  E) node of ranvier