Nervous System

Question 1

Collection of axons wrapped in connective tissue

Answer 1

Nerve

Question 2

Nerve cell, excitable transmit electrical signals

Answer 2

Neuron

Question 3

Nerve fibers

Answer 3

Axons

Question 4

Functions of nervous system

Answer 4

Sensory input
Integration
Motor output

Question 5

Outside CNS consists of nerves extend from brain and spinal cord

Answer 5

Cranial nerves, spinal nerves, ganglia

Question 6

PNS divided into 2 divisions

Answer 6

Sensory (afferent): signals picked up by sensory receptors throughout the body and carried by nerve fibers of PNS to CNS
Motor (efferent): signals carried away from CNS by nerve fibers of PNS to innervate muscles and glands

Question 7

Motor division is divided into

Answer 7

Somatic: conducts impulses away from CNS to skeletal muscles (voluntary control)
Autonomic: conducts impulses away from CNS to viscera (involuntary control)

Question 8

Autonomic divided into

Answer 8

Sympathetic: fight or flight
Parasympathetic: rest and digest Maintain basic body functions

Question 9

Non-excitable support cells surround neurons

Answer 9

Neuroglia

Question 10

Clusters of nerve cell bodies in CNS

Answer 10

Nuclei

Question 11

Clusters of nerve cell bodies outside CNS

Answer 11

Ganglia

Question 12

Processes branch out from cell body
Receiving signals & direct signals towards cell body

Answer 12

Dendrites

Question 13

Single process arises from cell body
Cone shaped region near cell body

Answer 13

Axons
Axon hillock

Question 14

Site where nerves communicate with one another

Answer 14

Synapse

Question 15

Neuron conducts signals toward a synapse

Answer 15

Presynaptic neuron

Question 16

Neuron transmits signals away from a synapse

Answer 16

Postsynaptic neuron

Question 17

Gap in between presynaptic and postsynaptic

Answer 17

Synaptic cleft

Question 18

Two distinct processes: one dendrite & one axon with a cell body in between

Answer 18

Bipolar neurons

Question 19

Short single process emerges from cell body & divides into an inverted T into 2 long branches
1 branch- central into CNS = central process
Other branch- extends peripherally = peripheral process
Most sensory neurons of PNS are these

Answer 19

Unipolar (pseudounipolar) neurons

Question 20

2 or more dendrites and single axon
Most abundant
All motor neurons are these

Answer 20

Multipolar neurons

Question 21

Lie between motor and sensory neurons
Most are multipolar and found only in CNS

Answer 21

Interneurons

Question 22

Star shaped cells
Most abundant type of glial cel in CNS
Form blood brain barrier, maintain ion and neurotransmitter concentrations

Answer 22

Astrocytes

Question 23

Macrophages of the CNS
Remove debris, damaged tissues, and infectious microorganisms

Answer 23

Microglia

Question 24

Production & circulation of cerebrospinal fluid (CSF)

Answer 24

Ependymal cells

Question 25

Produce myelin Wrap myelin around multiple axons

Answer 25

Oligodendrocytes

Question 26

In PNS, myelinate one segment of one axon

Answer 26

Schwann cells

Question 27

Glial cells in PNS

Answer 27

Satellite cells

Question 28

Lipid rich sheath surrounds axons Insulating layer prevents leakage of electrical current, increasing speed of impulse conduction

Answer 28

Myelin sheaths

Question 29

Gaps in myelin sheath

Answer 29

Nodes of ranvier

Question 30

Nerve impulses jump from cell membrane of one myelin sheath gap to the next, increases speed impulse conduction

Answer 30

Saltatory conduction

Question 31

Composed of cell bodies, dendrites, neuroglia, unmyelinated axons Found in outer portion of brain and in inner portion of spinal cord

Answer 31

Gray matter

Question 32

Myelinated axons Inner portion of brain and outer portion of spinal cord

Answer 32

White matter

Question 33

Ascending axons in white matter of spinal cord

Answer 33

Bring sensory information from PNS to brain

Question 34

Descending axons in white matter of spinal cord

Answer 34

Bring motor information from brain to the body

Question 35

Connective tissue surrounding outside of nerve

Answer 35

Epineurium

Question 36

Connective tissue surrounding a nerve fascicle

Answer 36

Perineurium

Question 37

Bundle of nerve fibers (axons)

Answer 37

Fascicle

Question 38

Connective tissue surrounding an individual nerve fiber

Answer 38

Endoneurium

Question 39

Sensory neurons of PNS transmit sensory information from receptors

Answer 39

To CNS

Question 40

Motor nerves of PNS transmit motor information from CNS

Answer 40

To effector organs

Question 41

Interneurons in CNS gray matter receive sensory information from afferent neuron

Answer 41

And direct a response stimulating a efferent neuron

Question 42

Involuntary rapid motor response to a stimulus

Answer 42

Reflex

Question 43

Chain of neurons responsible for reflexes Has 5 components

Answer 43

Reflex arc Receptor, sensory neuron, integration center, motor neuron, effector

Question 44

Site where stimulus acts located at peripheral end of sensory neuron

Answer 44

Receptor

Question 45

Transmits sensory impulse to CNS

Answer 45

Sensory neuron

Question 46

Consists of 1 or more synapses in gray matter of CNS Directs response from sensory signal

Answer 46

Integration center

Question 47

Transmits motor impulses away from CNS to an effector in periphery

Answer 47

Motor neuron

Question 48

Muscle or gland that contracts or secretes

Answer 48

Effector

Question 49

Reflex only one synapse is present in reflex arc No interneuron Sensory neuron synapses directly on motor Knee jerk reflex

Answer 49

Monosynaptic reflex

Question 50

More than one synapse in reflex arc At least one interneuron Withdrawal reflex

Answer 50

Polysynaptic reflex arc

Question 51

Pain sensed through receptor in skin Sensory information sent to CNS activating interneuron Motor neuron going to forearm flexors is stimulated causing muscle contraction withdrawals hand away from painful stimulus

Answer 51

Withdrawal reflex

Question 52

Autoimmune demyelination’s disease of CNS Lymphocytes destroys myelin & inflammation Scarring of myelin occurs along white matter Vision disturbances, weakness, paresthesias

Answer 52

Multiple Sclerosis

Question 53

Autoimmune disease of PNS Bacterial GI infection & respiratory infections Weakness begins in distal lower extremities & ascends to diaphragm = respiratory failure

Answer 53

Guillain-Barré syndrome