Nervous System & Neurons

Question 1

The nervous system includes

Answer 1

the brain, spinal cord, and nerves

Question 2

function of nervous system

Answer 2

coordinate the body’s systems by receiving and sending information

Question 3

maintains

Answer 3

homeostasis

Question 4

sensory (Afferent)

Answer 4

receives information

Question 5

Integrative

Answer 5

determines where information is sent

Question 6

motor (Efferent)

Answer 6

responds to signals

Question 7

two divisions of the nervous system include

Answer 7

central nervous system (CNS) & Peripheral Nervous System (PNS)

Question 8

central nervous system (CNS)

Answer 8

brain & spinal cord

Question 9

peripheral nervous system (PNS)

Answer 9

peripheral nerves through the body, includes 31 pairs of spinal nerves and 12 pairs of cranial nerves

Question 10

somatic nervous system

Answer 10

skeletal, voluntary

Question 11

autonomic nervous system

Answer 11

smooth muscles, glands, involuntary

Question 12

parasympathetic (peace)

Answer 12

rest and digest

Question 13

sympathetic (stress)

Answer 13

fight or flight

Question 14

neuron

Answer 14

mass of nerve cells that transmit information and functional unit of the nervous system

Question 15

cell body

Answer 15

contains the nucleus and other cell organlles

Question 16

dendrites

Answer 16

shorter, more numerous, receive infomation

Question 17

axons

Answer 17

single long fibers, conducts information away

Question 18

chromatophilic substance (rough ER)

Answer 18

transport system

Question 19

Myelin

Answer 19

insulation surrounding axons

Question 20

nodes of ranvier

Answer 20

gaps in the insulation

Question 21

Nodes of Ranvier

Answer 21

gaps in the insulation

Question 22

neurofibrils

Answer 22

fiber within the axon

Question 23

neurofibrils

Answer 23

fibers within the axon

Question 24

neurofibrils include

Answer 24

microglial cells, oligodendrocytes (CNS). astrocytes, ependymal cells, and Schwann cells.

Question 25

microglial cells

Answer 25

immune function, digest debris, kill bacteria

Question 26

oligodendrocytes (CNS)

Answer 26

make myelin sheath that provides insulation for axons, in the brain and spinal cord, makes CNS only in the oligodendrocytes

Question 27

astrocytes

Answer 27

connect blood vessels to neurons

Question 28

ependymal cells

Answer 28

form membranes around tissues

Question 29

Schwann cells

Answer 29

also, form insulating myelin sheath, found in the PNS

Question 30

myelin sheaths

Answer 30

insulate axons, gaps in the sheath are called Nodes of Ranvier

Question 31

myelinated (white matter)

Answer 31

myelinated axons

Question 32

unmyelinated (grey matter)

Answer 32

unmyelinated axons

Question 33

nerve impulses

Answer 33

weak electric current, like a wave

Question 34

1) neuron membrane maintains

Answer 34

resting potential

Question 35

2) threshold stimulus is

Answer 35

received

Question 36

3) Sodium (Na+) channels

Answer 36

open

Question 37

4) sodium ions diffuse inward,

Answer 37

depolarizing the membrane

Question 38

5) potassium channals

Answer 38

open

Question 39

6) potassium ions diffuse outward

Answer 39

repolarizing the membrane

Question 40

7) the resulting action potential causes a local

Answer 40

bioelectric current

Question 41

8) wave of __________ _____________ trvale the length of the axon as a neve impulse

Answer 41

action potentials

Question 42

nerve impulse

Answer 42

propagandation of action potentials along a nerve axon

Question 43

speed of an impulsr proportinate to

Answer 43

size of axon (greater diameter = faster impulse)

Question 44

myelinated axons conduct

Answer 44

impulses faster than unmyelinated axons