Central Nervous System (CNS)
Peripheral Nervous System
Somatic vs. Autonomic
Voluntary vs. Involuntary
What is a neuron?
Specialized cell, functional unit of the nervous system
Glial Cells
Sensory Receptors
Receives stimuli
Sensory Neurons
Transmit info received from sensory receptors to inter neurons (CNS), myelinated, PNS
Inter neurons
Motor Neurons
Effectors
Homeostasis
To maintain balance
Sympathetic
Prepares body for stress
Parasympathetic
“Rest and Digest”
Restores to normal balance
Label the neuron
Identify each type of neuron
Soma
Body/Cell body
Grey Matter
Unmyelinated neurons
Axon carries…
carries impulses away from cell body
Order of reflex arc
Depolarization
sodium channels open, Na flows in, becomes more +/ve
Sodium Potassium pump
Pumps 3Na in 2K out for axon to remain -/ve inside, restores concentration gradient
All or None principle
It reaches threshold or it doesn’t, cant change threshold
What happens when a neuron receives a threshold stimulus?
It becomes more permeable to Na ions and Na begins to rush into the cell, causes axon to become +/ve
Repolarization
Process when the cell returns to -/ve state, potassium channels open, k flows out