Ch.12, Nervous Tissue

Question 1

The ______ system and the _______ system work together to keep controlled conditions within limits that maintain health and homeostasis

Answer 1

nervous system and endocrine system

Question 2

What is the nervous system responsible for?

Answer 2

all our behaviors. memories, and movements

Question 3

The branch of medical science that deals with the normal functioning and disorders of the nervous system

Answer 3

neurology

Question 4

The CNS consists of…?

Answer 4

the brain and spinal cord

Question 5

The PNS consists of…?

Answer 5

cranial and spinal nerves with sensory (efferent) and motor (afferent) components, ganglia, and sensory receptors

Question 6

The ________ system consists of a variety of different receptors as well as sensory neurons

Answer 6

sensory system

Question 7

The _____ system conducts nerve impulses from the CNS to muscles and glands

Answer 7

motor system

Question 8

The PNS is also subdivided into …..

Answer 8

somatic (voluntary), autonomic (involuntary), and enteric nervous systems

Question 9

The somatic nervous system (SNS) consists of neurons that conduct impulses from ….

Answer 9

cutaneous and special sense receptors to the CNS, and motor neurons that conduct impulses from the CNS to skeletal muscle tissue

Question 10

The autonomic nervous system (ANS) contains sensory neurons from ….

Answer 10

visceral organs and motor neurons that convey impulses from the CNS to smooth muscle tissue, cardiac muscle tissue, and glands

Question 11

The motor part of the ANS consists of the …

Answer 11

sympathetic division and the parasympathetic division

Question 12

The enteric nervous system (ENS) consists of neurons in …

Answer 12

enteric plexus that extend the length of the GI tract

Question 13

Many neurons of the enteric plexus function …

Answer 13

independently of the ANS and CNS

Question 14

What do the sensory neurons of the ENS monitor?

Answer 14

chemical changes within the GI tract and stretching of its walls

Question 15

What do enteric motor neurons govern?

Answer 15

contraction of GI tract organs and activity of the GI tract endocrine cells

Question 16

What is the sensory function of the nervous systems? What neurons carry out the function?

Answer 16

to sense changes in the internal and external environment through sensory receptors
-sensory neurons

Question 17

What is the integrative function of the nervous systems? What neurons carry out the function?

Answer 17

analyze the sensory information, store some aspects, and make decisions regarding appropriate behaviors
-association or interneurons

Question 18

What is the motor function of the nervous systems? What neurons carry out the function?

Answer 18

respond to stimuli by initiating action
-motor neurons

Question 19

Neurons have the property of electrical ________

Answer 19

excitability

Question 20

What do most neurons, or nerve cells consist of

Answer 20

-a cell body (soma),
-many dendrites,
-and usually a single axon

Question 21

The cell body contains:

Answer 21

-a nucleus
-lysosomes
-mitochondria,
-a Golgi complex
-cytoplasmic inclusions (lipofuscin, chromatophilic substances, and neurofibrils)

Question 22

What are an orderly arrangement of rough ER

Answer 22

chromatophilic substances (Nissl bodies)

Question 23

What forms the cytoskeleton?

Answer 23

Neurofibrils

Question 24

What are the receiving or input portions of a neuron?

Answer 24

dendrites

Question 25

What does the axon do?

Answer 25

it conducts nerve impulses from the neuron to the dendrites or cell body of another neuron or to an effector organ of the body (muscle or gland)

Question 26

What is a synapse?

Answer 26

The site of functional contact between two neurons or between a neuron and an effector cell

Question 27

Axonal transport

Answer 27

a natural mechanism of intracellular transport in neurons -exploited by certain microorganisms to reach other parts of the nervous system

Question 28

What is used to classify the various neurons in the body?

Answer 28

both structural and functional features

Question 29

On the basis of the number of processes extending from the cell body, how are neurons classified?

Answer 29

-multipolar -bipolar -unipolar

Question 30

On the basis of function, how are neurons classified?

Answer 30

-sensory -association -motor

Question 31

Neuroglia

Answer 31

specialized tissue cells that support neurons, attach neurons to blood vessels, produce myelin sheath around axons, and carry phagocytosis

Question 32

Neuroglia in the CNS

Answer 32

-astrocytes -oligodendrocytes -microglia -ependymal cells

Question 33

Neuroglia in PNS

Answer 33

-neurolemmocytes -schwann cells -satellite cells

Question 34

Functions of astrocytes

Answer 34

-microfilaments for strength -blood brain barrier -regulate growth -maintain chemical environments -learning and memory

Question 35

Oligodendrocyte function

Answer 35

myelin sheath

Question 36

Microglial cells functions

Answer 36

phagocytes

Question 37

Ependymal cells functions

Answer 37

circulate cerebral spinal fluid

Question 38

Neuroglia cells functions

Answer 38

-schwann cells (myelin sheath) -satellite cells (exchange material between neuronal cell bodies and interstitial fluid)

Question 39

A multilayered lipid and protein covering

Answer 39

myelin sheath

Question 40

What produces the myelin sheath?

Answer 40

Schwann cells and oligodendrocytes

Question 41

Where is myelin sheath found?

Answer 41

it surrounds the axons of most neurons

Question 42

What does myelin sheath do?

Answer 42

it electrically insulates the axon and increases the speed of nerve impulse conduction

Question 43

What produces myelin sheath in the PNS?

Answer 43

schwann cells

Question 44

Neurolemma

Answer 44

the outer nucleated cytoplasmic layer of the Schwann cell

Question 45

What does the neurolemma do?

Answer 45

aids in regeneration in an injured axon by forming a regeneration tube that guides and stimulates regrowth of an axon

Question 46

What forms myelin sheaths for CNS axons?

Answer 46

oligodendrocytes -no neurolemma formed -no regrowth after injury occurs

Question 47

What is white matter composed of?

Answer 47

aggregations of myelinated processes

Question 48

What is gray matter composed of?

Answer 48

nerve cell bodies, dendrocytes, and axon terminals or bundles of unmyelinated axons and neuroglia

Question 49

How do excitable cells communicate?

Answer 49

action potentials or graded potentials

Question 50

Difference between action potentials and graded potentials

Answer 50

-action potentials allows communication over short and long distances -graded potentials is short distances only

Question 51

Gated ion channels respond to...

Answer 51

voltage changes, ligands, and mechanical pressure

Question 52

Voltage-gated channels respond to...

Answer 52

a direct change in the membrane potential

Question 53

Ligand-gated channels respond to...

Answer 53

a specific chemical stimulus

Question 54

Mechanically gated ion channels respond to...

Answer 54

mechanical vibration or pressure