U2

Question 1

at rest is the inside or outside of a cell more negative

Answer 1

inside is more negative

Question 2

what is an action potential

Answer 2

nerve impulse that stimulates effectors resulting in a change in RMP causing muscle contractions

Question 3

depolarization

Answer 3

stimulus causes Na channels to open
Na moves down concentration gradient
inside of cell becomes more positive

Question 4

repolarization

Answer 4

K channels open
K exits cell using ion-specific channels
cell becomes more negative

Question 5

neurons

Answer 5

cells involved in transmitting signals (impulses)

Question 6

saltatory conduction

Answer 6

propagation od action potentials in militated axons
allows for rapid transfer
reduces energy needed to re-enstate ap

Question 7

in myelinated axons ap only happens at

Answer 7

nodes of ranvier

Question 8

myelin sheath

Answer 8

insulates
formed by Schwann cells

Question 9

synapse

Answer 9

terminal region of axon
ap arriving at the synapse causes a controlled release of neurotransmitters

Question 10

steps in nerve impulses (action potentials)

Answer 10

• resting membrane is polarized
• depolarization
• generation of ap
• propagation of ap
• repolarization
• ionic conditions restored

Question 11

steps in signal transmission

Answer 11

• ap arrives
• ca enters cell via vesicles and pore like openings
• neurotransmitters released in synaptic cleft then bound ro synaptic membrane
• ion channels activated
• Na enters cell = depolarization
• neurotransmitters are broken down
• Na channels close

Question 12

3 organizational components of the nervous system

Answer 12

• sensory input
• integration
• motor output

Question 13

sensory systems pass info through _______ nerves to _____ and motor move through ______ nerves to ______

Answer 13

afferent, CNS
efferent, PNS

Question 14

what are axons called in the CNS vs PNS
cell bodies

Answer 14

• tract, nerve
• nuclei, ganglia

Question 15

endoneurium

Answer 15

insulates bundles of axons and prevents cross talk

Question 16

fascicles

Answer 16

axon bundles

Question 17

perineurium

Answer 17

protect fascicle

Question 18

epinerium

Answer 18

protect several fascicles

Question 19

the spinal cord has ____ matter on the inside and ______ matter outside

Answer 19

grey
white

Question 20

autonomic ns is responsible for _________ actions and somatic ns is for _________ and they are both part of the ______

Answer 20

involuntary (skeletal muscles, militated axons)
voluntary (smooth muscle, heart, glads, pre ganglionic militated axons that link to other ganglia)
PNS

Question 21

2 parts of the autonomic ns

Answer 21

parasympathetic (rest and digest)
sympathetic (fight or flight)

Question 22

glial cells

Answer 22

support transmission of nerve impulses

Question 23

what 3 cells form myelin sheath

Answer 23

Schwann cells
satellite cells
oligodendrocytes

Question 24

astrocytes

Answer 24

form scaffold that anchors neurons in place in CNS

Question 25

microglia

Answer 25

removes dead cells

Question 26

ependymal cells

Answer 26

line brain cavities

Question 27

4 major brain regions

Answer 27

- cerebrum - cerebellum - diencephalon - brainstem

Question 28

cerebrum

Answer 28

largest important for sensory and voluntary motor activity divided into left and right cerebral hemispheres central sulcus separates motor and sensory regions

Question 29

cerebellum

Answer 29

back of brain involuntary coordination of body movement

Question 30

diencephalon

Answer 30

top of brain stem enclosed by hemispheres

Question 31

3 parts of diencephalon

Answer 31

thalamus (relay station for sensory impulses before cerebral cortex) hypothalamus (regulates body temp, water balance, and metabolism) epithalamus (chloride plexus - CSF, and pineal glads - produces melatonin for circadian rhythms)

Question 32

3 parts of the brain stem

Answer 32

midbrain (conveys ascending and descending impulses between brain and spinal cord pons (act with medulla to control breathing) medulla (control heart rate, blood pressure, swallowing, and vomiting)

Question 33

spinal cord

Answer 33

neural connection between PNS and brain filled w CSF moved in through central canal

Question 34

spine

Answer 34

protects spinal cord from cervical to sacral region

Question 35

foramea

Answer 35

holes in vertebrae nerves leave through

Question 36

interneurons

Answer 36

communicate with one another along spinal cord allow for afferent sensory stimuli to be translated up or down spinal cord

Question 37

reflexes

Answer 37

responses to stimuli that are initiated in spinal cord rapid and involuntary

Question 38

example of a reflex

Answer 38

withdrawal reflex (contraction of some muscles and relaxation of others)

Question 39

5 basic elements of the reflex arc

Answer 39

- sensory receptor - sensory neurons (afferent) - spinal cord (integration) - motor neuron (efferent) - effector organ

Question 40

2 forms of reflexes

Answer 40

somatic (skeletal muscles) autonomic (smooth and cardiac muscles, secretion of glands)

Question 41

post ganglionic neruons

Answer 41

non militated connect to effector organs

Question 42

acetylcholine and noreoherine are released by _____ or ______________ axons to cause _______ or ______ responses respectively

Answer 42

pre or post ganglionic excitatory or inhibitory

Question 43

most organs are innervated by __________ and _________ divisions which tend to exert opposite axons on same organ depending on what the body needs

Answer 43

sympathetic parasympathetic