Learning Outcomes
• C11 – analyse the transmission of nerve impulses– Describe the structure of a neuron– Identify the function of dendrite, axon,
cell body, axoplasm, axomembrane– Differentiate between sensory, motor
and interneurons
Peripheral Nervous System
• PNS consists of nerves throughout the body
• Carries messages to and from the CNS
• Cell body contains the nucleus and organelles
• Axon transmits an impulse away from the cell body to the next cell
• Dendrite receives an impulse and transmits it to the cell body
• Axoplasm refers to the cytoplasm within the axon
• Axomembrane refers to the plasma membrane of the axon
• Schwann cells wrapped around the axon contain myelin (a specialized phospholipid) in their plasma membranes
Types of Neurons
• Sensory neurons carry impulses from sensory receptors to the CNS
• Have long dendrites• Motor neurons carry impulses from the
CNS to an effector (muscle or gland)• Have long axons• Interneurons connect other neurons to
the CNS