Chapter 7 Pt. 1

Question 1

The ________ ________ integrates and coordinates all the body’s varied activities

Answer 1

nervous system

Question 2

What are the 2 primary divisions of the nervous system?

Answer 2

1) Central Nervous System

2) Peripheral System

Question 3

What is the difference between the central nervous system and the peripheral system?

Answer 3

Central Nervous System- consisting of the brain and spinal cord

Peripheral System- consisting of all the nervous tissue in the body outside the brain and spinal cord

Question 4

What are Neurons?

Answer 4

excitable cells that generate and transmit messages

Question 5

Neurons are also known as ______ _____

Answer 5

nerve cells

Question 6

What are Neuroglia cells (glial cells)?

Answer 6

support and protect neurons

Question 7

__________ cells (_____ cells) outnumber neurons

Answer 7

Neuroglia cells (glial cells)

Question 8

What are nerve growth factors?

Answer 8

a steady supply of chemicals supplied by glial cells

Question 9

What is a myelin sheath?

Answer 9

glial cells that form insulating sheaths around axons

Question 10

What are the 3 categories of neurons?

Answer 10

1) sensory (or afferent) neurons
2) motor (or efferent) neurons
3) interneurons (or associate) neurons

Question 11

What are the characteristics of sensory (or afferent) neurons?

Answer 11

• conduct information toward the brain and spinal cord

- generally extend from sensory receptors

Question 12

What is a motor (or efferent) neuron?

Answer 12

carry information away from the brain and spinal cord to an effector

Question 13

What is an effector?

Answer 13

either a muscle, which will contract, or a gland, which will secrete its product

Question 14

What are the characteristics of interneurons (or associate) neurons?

Answer 14

are located between sensory and motor neurons

found only within the brain and spinal cord

Question 15

What are the most numerous nerve cells in the body?

Answer 15

interneurons (or associate) neurons

Question 16

What is amyotrophic lateral sclerosis (ALS)?

Answer 16

a progressive disease in which motor neurons die and stop sending messages to skeletal muscles

Question 17

amyotrophic lateral sclerosis (ALS) causes the person to lose control over _____, ____, and _____

Answer 17

arms
legs
body

Question 18

How does amyotrophic lateral sclerosis (ALS) cause death?

Answer 18

respiration failure

Question 19

Amyotrophic lateral sclerosis (ALS) is also known as ____ _______ ________

Answer 19

Lou Gehrig’s disease

Question 20

What are dendrites?

Answer 20

branching projections attached to a neuron

Question 21

_________ provide a huge surface for receiving signals form other cells

Answer 21

dendrites

Question 22

What is the cell body?

Answer 22

the enlarged central region; has all the normal organelles

Question 23

What is an axon?

Answer 23

a single one extension of the neuron

Question 24

What is a neurotransmitter?

Answer 24

alters the activity of the effector

Question 25

_____________ are released by the many branches at the end of the axon

Answer 25

Neurotransmitters

Question 26

Neurotransmitters are released by the many _________ at the end of the ______

Answer 26

branches | axons

Question 27

The _____ is the sending portion of the neuron, whereas the _________ and ____ _____ are typically the receiving portions

Answer 27

axon dendrites cell body

Question 28

What is a nerve?

Answer 28

a bundle of parallel axons, dendrites, or both arising from many neurons

Question 29

The structure of a neuron: 1) ________, receive information form other neurons or from the environment 2) the ____ ______ controls the cell’s metabolic activities 3) the ____ ______ integrates input from other neurons 4) an _____ conducts the nerve impulse away form the cell body 5) _____ ________ release chemicals called neurotransmitters that affect the activity of nearby nears or an effector

Answer 29

``` dendrites cell body cell body axon axon endings ```

Question 30

______ _______ increased the rate of conduction of a nerve impulse and helps repair it

Answer 30

Myelin sheath

Question 31

Myelin sheath increased the rate of __________ of a nerve impulse and helps ______ it

Answer 31

conduction | repair

Question 32

Myelin sheath plays a role in the ____________ of cut axons in the __________ nervous system

Answer 32

regeneration | peripheral

Question 33

What are Schwann Cells?

Answer 33

glial cells, outside the brain and spinal cord, that form neurons’ myelin sheaths

Question 34

The ______ _______ is kept alive by the Schwann cell’s nucleus and cytoplasm, which are squeezed to the _________ as the sheath forms

Answer 34

myelin sheath | periphery

Question 35

The myelin sheath is kept alive by the Schwann cell’s ________ and _________, which are squeezed to the periphery as the sheath forms

Answer 35

nucleus | cytoplasm

Question 36

What are nodes of Ranvier?

Answer 36

the gaps between adjacent Schwann cells, where the axon is exposed to the extracellular environment

Question 37

What is saltatory conduction?

Answer 37

a transmission of a nerve impulse “jumps” successively form one node of Ranvier to the next

Question 38

_______ means to jump

Answer 38

saltare

Question 39

What is multiple sclerosis?

Answer 39

a disease in which the myelin sheaths in the brain and spinal cord are progressively destroyed

Question 40

the damaged regions of myelin become hardened scared called _________

Answer 40

scleroses

Question 41

_________, interfere with the transmission of nerve impulses

Answer 41

scleroses