Quiz #3

Question 1

Nervous System

Answer 1

communication network that enables animal to adjust to internal and external environmental changes

Question 2

What do sensory components do?

Answer 2

detect environmental changes

Question 3

What do motor components do?

Answer 3

provide response to processed information

Question 3

What do integrative components do?

Answer 3

process sensory data coupled with information stored in memory

Question 4

What are the two types of cells of the nervous system?

Answer 4

1. neurons
2. glial

Question 5

What are neurons?

Answer 5

transmit nerve impulses and join with others via synapses

Question 6

What are glial cells?

Answer 6

provide service to neurons and their environment

Question 7

How many neurons do humans have? How many glial cells?

Answer 7

100 million neurons and 10x glial cells

Question 8

What are the three components of a neuron?

Answer 8

1. cell body
2. dendrites (many)
3. axon (one)

Question 9

What are dendrites? What do they do? What do the look like?(3)

Answer 9

1. conduct impulses towards cell body
2. sites for receiving information from other neurons
3. highly branched, large surface area for communication with axons

Question 10

What does an axon do?

Answer 10

conduct impulses away from cell body

Question 11

What is a nerve fiber composed of?

Answer 11

an axon and its myelin covering if present

Question 12

What is a neurilemma? Where is located?

Answer 12

Surrounds the myelin sheath
Located in a myelinated axon

Question 13

What is an axolemma?

Answer 13

Plasma membrane of axon, beneath the myelin sheath

Question 14

What are Nodes of Ranvier? Where are they found? Function?

Answer 14

1. regularly spaced, myelin-free
2. gaps along myelinated axon
3. the axolemma is directly exposed to fluid and exchanges electrolytes and nutrients

Question 15

Whare is the telodendric zone located?

Answer 15

terminal branches of axon

Question 16

What does the polarity of a neuron refer to?

Answer 16

the number of poles or processes that stem from cell bodies

Question 17

What is a bipolar neuron? (Length, composition, location)

Answer 17

Short
One axon and one dendrite
Retina and olfactory region (nose)

Question 18

What is a multipolar neuron? (Length, composition, location)

Answer 18

Typically long
Many dendrites and one axon
Most are located in the CNS

Question 19

What is a nucleus?

Answer 19

group of nerve cell bodies within brain and spinal cord (CNS)

Question 20

What is a ganglion?

Answer 20

group of nerve cell bodies outside of brain and spinal cord (PNS)

Question 21

What is a tract/fasciculus?

Answer 21

bundle of parallel fibers within brain and spinal cord (CNS)

Question 22

What is a nerve?

Answer 22

bundle of neuron fibers outside brain and spinal cord (PNS)

Question 23

Synapse

Answer 23

continuity from one neuron to the next

Question 24

What is the synaptic gap? How are impulses transmitted?

Answer 24

no physical contact of neurons in the space between neurons. Impulses are transmitted chemically.

Question 25

What are the three characteristics of a synapse?

Answer 25

1. one-way conduction (direction) 2. facilitation (repeated impulses provide easier subsequent transmission) 3. greater fatigability then neurons (repetitive impulses fade, tire faster)

Question 26

A neuron's axon terminal bud is in ___ ___ to another ____. The ___ ___ fits into the ____ of the ___ ___ cell membrane

Answer 26

1. close 2. proximity 3. neuron 4. terminal 5. bulb 6. postsynaptic

Question 27

Synaptic cleft

Answer 27

gap between axon terminal and postsynaptic cell

Question 28

Where are synaptic vesicles located? What do they contain?

Answer 28

1. terminal bulb 2. neurotransmitters

Question 29

Oligodendrocytes

Answer 29

myelin sheath formation in PNS

Question 30

Function of Schwann cells

Answer 30

myelin sheath formation in PNS

Question 31

Astrocytes (4, location and function)

Answer 31

1. numerous, star shaped 2. provide support and blood vessel nourishment 3. release excitatory neurotransmitter glutamate in response to stimulation 4. CNS

Question 32

Ependymal cells (location and function)

Answer 32

1. Line ventricles of brain and central canal of spinal cord 2. Unite with capillaries to form choroid plexus

Question 33

Choroid Plexus (location and function)

Answer 33

1. in the ventricles 2. produces cerebrospinal fluid

Question 34

Myelin (composition, function)

Answer 34

1. White lipid substance 2. forms sheath around nerve fibers and serves as electrical insulator

Question 35

How are myelin sheaths formed in the CNS and the PNS

Answer 35

1. In CNS: oligodendrocytes 2. In PNS: Schwann Cells

Question 36

Why are unmyelinated fibers not insulated?

Answer 36

they are in direct association with extracellular fluid

Question 37

Myelinated means ___ conduction?

Answer 37

faster

Question 38

Schwann cell (composition, 3)

Answer 38

1. cytoplasm contains myelin and wraps around nerve fiber many times 2. nucleus lies in the cell beneath the neurolemma 3. one cell around on axon

Question 39

Oligodendrocyte (composition, 3)

Answer 39

1. cytoplasm has multiple extension and each wraps around a nerve fiber 2. one cell provides sheath for multiple axon locations 3. axon bulges at node and is exposed to extracellular space

Question 40

Depolarization

Answer 40

occurs due to sodium and potassium entering the cell

Question 41

Saltatory conduction

Answer 41

depolarizing action potential jumps from node to node, traveling along myelinated segments

Question 42

PNS

Answer 42

outer cytoplasmic processes of adjacent neurolemmocytes (Schwann cells) overlap to restrict exposure to extracellular space

Question 43

CNS

Answer 43

myelin formed by oligodendrocytes and nodes are broadly exposed to extracellular space

Question 44

What is the CNS composed of?

Answer 44

brain and spinal cord

Question 45

What is the PNS composed of? What are the two divisions?

Answer 45

1. cranial and spinal nerves 2. somatic (voluntary) and autonomic (involuntary)

Question 46

Autonomic Nervous System (ANS) (3 divisions)

Answer 46

1. sympathetic NS 2. parasympathetic NS 3. enteric NS

Question 47

Sympathetic Nervous System

Answer 47

fight or flight

Question 48

Parasympathetic Nervous System

Answer 48

rest and digest