Nervous System

Question 1

Sensory (afferent)

Answer 1

functional- receive sensory information from receptors that detect stimuli and transmit info to CNS

Question 2

Motor (efferent)

Answer 2

functional- initiate and transmit motor output from CNS to effectors- controls tissue and glands

Question 3

Association

Answer 3

Functional- receive, process, and store information and “decide” how to respond

Question 4

Multipolar

Answer 4

Structural- skeletal/motor and interneurons (most)

Question 5

Unipolar

Answer 5

Structural- sensory

Question 6

Bipolar

Answer 6

Structural- sensory- olfactory epithelium of nose and retina of eye

Question 7

Astrocytes

Answer 7

CNS- start from capillary and attach to neuron; help form blood-brain barrier

Question 8

Microglia

Answer 8

CNS- defend against bacteria/ infection; engulf debris, dead/dying neurons (act as lysosome)

Question 9

Oligodendrocyte

Answer 9

CNS- wraps around (like myelinated axon); allows faster action potential conduction

Question 10

Ependymal cell

Answer 10

CNS- assist in production of cerebral spinal fluid; line brain

Question 11

Schwann cell (neurolemmocyte)

Answer 11

PNS- wraps around axon like a jelly roll; allow faster action potential conduction

Question 12

Satellite cells

Answer 12

PNS- regulate nutrients and waste

Question 13

Action potential

Answer 13

self-propogating change in membrane potential occurring in excitable cells

Question 14

Axon terminal

Answer 14

telodendria- fine terminal extensions formed from axon and collateral branches at distal end

Question 15

Depolarization

Answer 15

making membrane more positive; change in membrane potential or voltage to a more positive value

Question 16

excitatory postsynaptic potential

Answer 16

EPSP- Sodium in and Potassium out resulting in a temporary less negative state across the membrane

Question 17

hyperpolarization

Answer 17

change in the membrane potential to a value more negative than the resting potential

Question 18

inhibitory postsynaptic potential

Answer 18

IPSP- potassium out and chlorine in resulting in a temporary more negative state

Question 19

local potential (postsynaptic potential)

Answer 19

graded potentials that occur in post synaptic neurons; graded potentials occur in the receptive segment of a neuron due to opening of chemically gated channels

Question 20

neurotransmitter

Answer 20

chemical messenger; chemical released from a neuron that delivers information to another cell

Question 21

postsynaptic neuron

Answer 21

distal side of a synaptic cleft; signal receiver or target

Question 22

presynaptic neuron

Answer 22

proximal side of a synaptic cleft; signal producer

Question 23

repolarization

Answer 23

change in membrane potential from a depolarized value back to the resting value

Question 24

resting membrane potential

Answer 24

RMP- voltage measured across the plasma membrane of an excitable cell at rest

Question 25

synapse

Answer 25

in close proximity to dendrite on other neuron; where signal change occurs; functional contact of a nerve cell with another nerve cell; effector or receptor

Question 26

synaptic vesicle

Answer 26

contains neurotransmitter; package of plasma membrane enclosing neurotransmitter molecules in the synaptic knob

Question 27

threshold stimulus

Answer 27

minimum membrane potential for an action potential to occur

Question 28

cell body

Answer 28

soma- receive, integrate, and send out signal; neuron’s control center

Question 29

nucleus

Answer 29

housed in cell body; houses nucleolus where ribosomes are formed

Question 30

Nissl body

Answer 30

chromatophilic substance; free and bound ribosomes together; produce proteins

Question 31

dendrites

Answer 31

receive message and send to cell body for processing

Question 32

axon

Answer 32

sends signal to muscle, skin, another neuron

Question 33

axon hillock

Answer 33

cell body tapers to axon; where action potential is generated

Question 34

axon terminals/ synaptic end bulbs (knobs)

Answer 34

extreme tips containing synaptic vesicles; meets at functional junction called synapse

Question 35

myelin sheath

Answer 35

fatty substance that insulates nerves and helps conduct message faster

Question 36

node of rangier (neurofibril node)

Answer 36

portion between myelin; where action potential occurs