LESSON 1_ BASIC CELLS OF THE NERVOUS SYSTEM

Question 1

-functional cell of the nervous system
-transmits impulses up to 250 mph

Answer 1

Neuron

Question 2

receives stimulus and carries it impulses towards the cell body

Answer 2

Dendrite

Question 3

• with nucleus
• nucleus and most of the cytoplasm

Answer 3

Cell body

Question 4

-fiber which carries impulses away from the cell

Answer 4

Axon

Question 5

-cells which produce myelin or fat layer in the peripheral nervous system

Answer 5

Schwann Cells

Question 6

-dance lipid layer which insulates the axon
-makes the axon look great

Answer 6

Myelin Sheath

Question 7

-gaps or nodes in the myelin sheeth

Answer 7

Node of Ranvier

Question 8

impulses travel…

Answer 8

from the dendrite -> cell body -> axon

Question 9

the three types of neurons are

Answer 9

sensory neurons
motor neurons
interneurons

Question 10

bring messages from CNS

Answer 10

sensory neurons

Question 11

carry messages from CNS

Answer 11

Motor neurons

Question 12

between sensory and motor neurons in the CNS

Answer 12

Interneurons

Question 13

a change in the environment with sufficient strength to initiate a response

Answer 13

stimulus

Question 14

is the ability of a neuron to respond to the stimulus and convert it into a nerve impulse

Answer 14

excitability

Question 15

the stimulus is either strong enough to start an impulse or nothing happens

Answer 15

all of nothing rule

Question 16

-are always the same strength along a given neuron and they are;

-self propagation

-once it starts it continues to the end of the neuron in only one direction from then right to cell body to axon

Answer 16

impulses

Question 17

causes a movement of ions across the cell membrane to the nerve cell

Answer 17

nerve impulse

Question 18

are small gaps or spaces between the action of one neuron and the dendrite of another

it is a junction between neurons which causes neurotransmitters to start the impulse in the second neuron or an effector (muscle or gland)

insures one way transmission of impulses

Answer 18

synapses

Question 19

chemicals in the junction which allow impulses to be started in the second neuron

Answer 19

neurotransmitters

Question 20

reacts to a stimulus

Answer 20

receptor

Question 21

conducts impulses to the CNS

Answer 21

afferent pathway or sensory neuron

Question 22

consists of one or more synopsis in the CNS most are in the spine

Answer 22

synapses

Question 23

conducts impulses from the cns to the effector

Answer 23

Efferent pathway or motor neuron

Question 24

muscle fibers or glands response by contracting or secreting a product

Answer 24

effector

Question 25

are the three coverings around the brain and spine and health cushion protect and nurse the brain and spinal cord

Answer 25

meninges

Question 26

the most outer layer of the meninges which is very tough

Answer 26

dura mater

Question 27

is the middle layer and adheres to the dura mater and has web like attachment to the innermost layer the pia mater

Answer 27

arachnoid

Question 28

is very thin transparent but tough and covers the entire brain follow it out with crevices (sulci) and spinal cord

Answer 28

pia mater

Question 29

buffers ,nourishes and detoxifies the brain and spinal cord flow through the subarachnoid space between the arachnoid meter and the pia mater

Answer 29

cerebrospinal fluid