central nervous system

the brain and spinal cord

peripheral nervous system

nerves that connect the CNS with the rest of the body

the nervous system performs three general functions

(1) sensory function - sense

(2) integrative function - figure it out

(3) motor function - fix it

neuroglia or glial

support, insulate, nourish, and care for delicate neurons

they DO NOT conduct glial cell

neuroglia

Most abundent glial cell

Astrocytes

most important in the transmission of information

neuron

nonmitotic

DO NOT replicate when injured

myelin

fatty material that encases most of the nerve fiber

sensory neuron

carries information from the periphery

motor neuron

makes you move

interneuron

between sensation and motor neurons.

they play a role in thinking, learning, and memory

saltatory conduction

nerve impulse "jumping" from node to node

organism most associated with saltatory conduction

kangaroo

primary source of energy for the brain

glucose

low blood glucose levels result in

hypoglycemia

the grooves that separate the gyri

sulci

dopamine

largely responsible for the activity of the basal nuclei

action potential

a process of polarization, depolarization, and repolarization

polarization

the resting state of a neuron. no nerve impulse is being transmitted.

the cell is quiet

depolarizatin

the neuron is stimulated a change occurs in the cells electrical state

depolarization

cell returning to its resting place. unless the cell repolarizes. it cannot be stimulated again

refractory period

the cells unresponsive period

the phases of the nerve impulse are caused by

the movement of ions, particularly Na+ and K+

the brain is divided into four major areas

the cerebrum, the diencephalon, the brain stem, and the cerebellum

parietal lobe

located behind the central sulcus

primarily concerned with receiving general sensory information from the body

also concerned with reading, speech, and taste

medulla oblongata

often called the vital center because it controls heart rate, bp, and respiratory

always assess the respiratory rate before administering a narcotic, if less than 10 do NOT administer

cerebellum

damage to the cerebellum produces jerky muscle movements, staggering gait, and difficultly maintaining balance or equilibrium

limbic system

functions in emotional states and behavior

reticular formation

concerned with the sleep-wake cycle and consciousness