Nervous System (Lab)

Question 1

astrocyte

Answer 1

star shaped neuroglia between blood vessels and neurons

Question 2

axon

Answer 2

nerve fiber arriving from a slight elevation of the cell body that conducts an impulse (action potential) away from the cell body

Question 3

interneurons

Answer 3

transmits an impulse from sensory to motor neuron within the CNS

Question 4

Microglia

Answer 4

phagocytic neuroglia

Question 5

Motor (Afferent) Neuron

Answer 5

transmits impulse into the brain or spinal cord to effectors (muscle and glands)

Question 6

Myelin sheath

Answer 6

a substance of Schwann cell composed of lipoprotein that insulates axons and increases impulse speed

Question 7

Neurolemma

Answer 7

a sheath of Schwann cell containing cytoplasm and nucleus that encloses myelin

Question 8

Neurofibrils

Answer 8

a network of fine threads extending into nerve fiber

Question 9

oligodendrocytes

Answer 9

myelin-forming neuroglia in the brain and spinal chord

Question 10

dendrite

Answer 10

neuron process with many branches that conducts an impulse

Question 11

Sensory (Efferent) Neurons

Answer 11

transmits impulse into the brain or spinal chord from receptors

Question 12

what is included in the CNS

Answer 12

brain and spinal chord

Question 13

What’s included in the PNS

Answer 13

cranial and spinal nerves

Question 14

the outermost layer of a nerve is called

Answer 14

Epineurium

Question 15

what is the layer that lines one fascicle of the nerve

Answer 15

Perineurium

Question 16

what is the layer that lines the individual nerve fibers?

Answer 16

endoneurium

Question 17

dura mater

Answer 17

the outermost layer of the brain and spinal cord

Question 18

pia mater

Answer 18

innermost layer covering

Question 19

arachnoid mater

Answer 19

middle layer

Question 20

subarachnoid space

Answer 20

space between the arachnoid mater and the pia mater

Question 21

what makes up the brain stem

Answer 21

medulla oblongata, pons, midbrain

Question 22

where is sodium mostly located?

Answer 22

outside

Question 23

where if potassium located

Answer 23

inside

Question 24

If the membrane’s resting potential decreases (in other words, the inside of the cell becomes less negative), the membrane is said to be

Answer 24

depolarized

Question 25

what is considered reaching threshold?

Answer 25

reaching -55 mV

Question 26

what occurs at threshold?

Answer 26

Sodium gated channels open and sodium comes flooding into the cell, causing further depolarization up to (40mV)

Question 27

what also occurs at threshold ?

Answer 27

The gated potassium channels also open, allowing potassium to move out of the cell

Question 28

the membrane potential being overly negative ?

Answer 28

hyper polarization

Question 29

repolarization

Answer 29

returning to the resting potential

Question 30

the greater the ____ the greater the speed of the impulse

Answer 30

diameter