Nervous System

Front 1

myelin

Back 1

- produced by glial cells
- insulating sumstance that allows axons to conduct impulses faster

Front 2

Shwann cells

Back 2

- produce myelin in peripheral nervous system

Front 3

Oligodendrocytes

Back 3

- produce myelin in the central nervous system

Front 4

Nodes of Ranvier

Back 4

- gapes between myelin sheath

Front 5

hyperpolarization

Back 5

- more negative inside than normal

Front 6

refractory period

Back 6

- immediately after action potential
- difficult to initiatie another action potential

Front 7

neuronal information

Back 7

- coded by frequency and number of action potentials and NOT the size of action potential (all-or-none response)

Front 8

Na+ electrochemical gradient

Back 8

Na+ wants to go into the cell because it is more negative inside (electrical gradient) and because there is less Na+ inside (chemical grandient)

Front 9

saltatory conduction

Back 9

jumping from node to node

Front 10

effector cells

Back 10

postsynaptic cells other than neurons (muscles or glands)

Front 11

Neurotransmitters are removed by a variety of ways...

Back 11

- taken back up into nerve terminal
- degraded by an enzyme (acetylcholinesterase) located in the synapse
- diffuse out of synapse

Front 12

afferent neurons

Back 12

- neurons that carry information TO brain or spinal cord

Front 13

efferent neurons

Back 13

- neurons that carry commands FROM the brain or spinal cord to varius parts of the body

Front 14

ganglia

Back 14

clusters of neuronal cell bodies located at the periphery

Front 15

central nervous system

Back 15

- brain
- spinal cord

Front 16

gray matter

Back 16

cell bodies

Front 17

white matter

Back 17

myelinated axons

Front 18

forebrain

Back 18

- cerebral cortex
- thalamus
- hypothalamus

Front 19

cerebral cortex

Back 19

- processes and integrates sensory input and motor responses
- important for memory and creative thought

Front 20

thalamus

Back 20

- relay and integration center for spinal cord and cerebral cortex

Front 21

hypothalamus

Back 21

- controls visceral functions (hunger, thirst, sex drive, water balance, blood pressure, temperature)
- tole in control of endocrine system

Front 22

midbrain

Back 22

- relay center for visual and auditory impulses
- role in motor control

Front 23

hindbrain

Back 23

- cerebellum
- pons
- medulla

Front 24

cerebellum

Back 24

- modulate motor impulses initiated by motor cortex
- maintain balance, hand-eye coordination, and timing of rapid movements

Front 25

pons

Back 25

- relay center to allow cortex to communicate with cerebellum

Front 26

medulla

Back 26

- contrals vital functions (breathing, heart rate, gastrointestinal activity)

Front 27

brainstem

Back 27

midbrain, pons, and medulla

Front 28

sensory information in spinal cord

Back 28

- sensory info enters spinal cord dorsally
- cel bodies of sensory neurons located in the dorsal root ganglia

Front 29

motor information in spinal cord

Back 29

- motor info exits spinal cord ventrally

Front 30

Peripheral nervous system

Back 30

- somatic and autonomic nervous system

Front 31

somatic nervous system

Back 31

- innervates skeletal muscles
- responsible for voluntary movement

Front 32

motor neuron neurotransmitter

Back 32

- acetylcholine

Front 33

monsynaptic reflex pathway

Back 33

- only one synpase between sensory neuron and motor neuron
- knee-jerk reflex

Front 34

polysynaptic reflex pathway

Back 34

- sensory neurons synpase with more than one motor neuron
- withdrawl reflex

Front 35

autonomic nervous system

Back 35

- regulates involuntary movements
- innervates cardiac and smooth muscle
- blood pressure cntrol, gastrointestinal motility, respiration, excretory, reproductive processes
- has 2-neuron system

Front 36

2-neuron system

Back 36

- preganglionic neuron has cell body located within CNS and its axon synapses in peripheral ganglia
- postsynaptic neuron has cell body in ganglia and synapses on cardiac or smooth muscle

Front 37

sympathetic nervous systems

Back 37

- fight of flight
- increase heart rate and breathing rate
- directs blood away from skin and toward muscles
- decrease digestion
- pupil dilation

Front 38

parasympathetic nervous system

Back 38

- acts to conserve energy and restore body to resting activity levels following exertion
- lower heart rate, increase digestion
- rest and digest

Front 39

vagus nerve

Back 39

- parasympathetic nerve
- innervates thoracic and abdominal viscera

Front 40

interoceptors

Back 40

monitor internal enviornment (blood pressure)

Front 41

proprioceptors

Back 41

transmit info regardin position of body

Front 42

exteroceptors

Back 42

sense things in external environment (light, sound, taste, pain...)

Front 43

retina

Back 43

contains photoreceptors that sense light

Front 44

cornea

Back 44

- at front of eye
- bends and focuses light rates

Front 45

iris

Back 45

muscle that controls diameter of iris

Front 46

ciliary musces

Back 46

control lens shape to focus image onto retina

Front 47

cones

Back 47

- respond to high-intensity light
- senstive to color

Front 48

rods

Back 48

- respond to low-intensity light
- night vision

Front 49

fovea

Back 49

- small area on retina that is packed with cones
- important for high acuity vision

Front 50

tympanic membrane

Back 50

- ear drum
- vibrates at same frequency as incoming sound
- transmits vibrations to three bones

Front 51

three bones in ear

Back 51

malleus, incus, stapes
- amplify stimulus and transmit it through oval window leading to inner ear

Front 52

cochlea

Back 52

- contains organ of Corti

Front 53

organ of Corti

Back 53

- in cochlea
- has hair cells that transduce action potentials that travel via auditory nerve to brain

Front 54

endolymph

Back 54

- fluid filling semicircular canals

Front 55

olfactory bulbs

Back 55

- olfactory receptors joing to form olfactory nerves that go to olfactory bulbes in base of brain