Nervous System I

Question 1

What are the functions of the nervous system?

Answer 1

receives environmental stimuli from receptors, transmits information to effectors, regulates internal environment, storage site for information

Question 2

What are the two subdivisions of the nervous system?

Answer 2

central nervous system, peripheral nervous system

Question 3

what two systems is the peripheral nervous system divided into?

Answer 3

the somatic nervous system, and autonomic nervous system

Question 4

what does the CNS contain?

Answer 4

brain and spinal cord, enclosed by bone

Question 5

what does the PNS contain?

Answer 5

cranial nerves and spinal nerves

Question 6

what is a neuron?

Answer 6

the basic functional unit of the nervous system

Question 7

What is the soma? what does it contain?

Answer 7

the cell body of a neuron, contains nucleus and metabolic machinery

Question 8

What is the function of dendrites?

Answer 8

receive neurotransmitters from other neurons at synapses, transmits information to cell body via graded potentials

Question 9

what is an axon?

Answer 9

long cytoplasmic process that transmits action potentials over long distances (up to one meter)

Question 10

what are telodendria?

Answer 10

terminal branches of axon (ending in terminal button) that release at synapses

Question 11

what are action potentials?

Answer 11

nerve impulses

Question 12

What are the three types of neurons?

Answer 12

bipolar, unipolar, multipolar

Question 13

What is the structure of bipolar neurons? give an example.

Answer 13

soma located near the middle of the axon.
e.x. retinal neurons

Question 14

What is the structure of unipolar neurons? give an example.

Answer 14

soma lies off to one side of the axon
e.x. sensory neurons

Question 15

What is the structure of multipolar neurons? give an example.

Answer 15

soma lies very close to dendrites (e.x. motor neurons)

Question 16

What is the function of afferent (sensory) neurons?

Answer 16

carry impulses from receptor cells to the CNS (pain or thermal receptors etc.)

Question 17

what is the function of efferent (motor) neurons?

Answer 17

carry impulses from the CNS to effectors (muscles or glands)

Question 18

what is a nerve?

Answer 18

cord like structure containing many axons within the PNS

Question 19

Nerves are surrounded by _________

Answer 19

epineurium (connective tissue layer)

Question 20

bundles of axons are surrounded by ________

Answer 20

perineurium (connective tissue layer)

Question 21

axons are surrounded by _________

Answer 21

endoneurium (connective tissue layer)

Question 22

what is a tract?

Answer 22

bundle of axons connecting different parts of the CNS

Question 23

what is a ganglion? give an example

Answer 23

a cluster of neural cell bodies of the PNS (dorsal root ganglion)

Question 24

what is the nucleus? give an example

Answer 24

a cluster of neural cell bodies of the CNS (thalamus)

Question 25

The spinal cord occupies the ____________ canal of vertebrae

Answer 25

vertebral (neural)

Question 26

Where does the spinal cord begin?

Answer 26

foramen magnum of the skull

Question 27

where does the spinal cord end in humans?

Answer 27

lumbar region (L1-L2) continues as collection of spinal nerves

Question 28

__________ and _________ rootlets emerge from spinal cord

Answer 28

dorsal and ventral

Question 29

spinal nerves exit the spinal cord via the ___________ foramina then divide into the_________ and ________ rami

Answer 29

intervertebral, dorsal, ventral

Question 30

what is metamerism?

Answer 30

segmentation

Question 31

Spinal nerves exhibit _________. a specific spinal nerve innervates specific __________ and __________

Answer 31

metamerism, myotomes, dermatomes

Question 32

What does gray matter consist of?

Answer 32

neuronal cell bodies

Question 33

what does white matter consist of?

Answer 33

myelinated axons that form ascending (sensory) and descending (motor) fiber tracts

Question 34

what is the spinothalamic tract?

Answer 34

one of many ascending tracts originating the the spinal cord and extending to the brain

Question 35

what is the function of the spinothalamic tract?

Answer 35

transmits information to the brain about pain, temperature, pressure, and crude touch

Question 36

axons of the spinothalamic tract ______ to the other side of the spinal cord

Answer 36

decussate

Question 37

1st order sensory neuron axons from skin receptors enter the ________ of the spinal cord and synapse with 2nd order sensory neurons (spinothalamic tract cells) in the ________

Answer 37

dorsal root, dorsal horn

Question 38

axons travel up the brainstem as ___________ tract to the thalamus

Answer 38

spinothalamic

Question 39

what is the corticospinal tract?

Answer 39

one of many descending tracts originating in brain and extending to the spinal cord

Question 40

neuronal cell bodies in the motor cortex of the corticospinal tract send axons _______ through the _______ and ________

Answer 40

down, brain stem, spinal cord

Question 41

most axons of the corticospinal tract ________ to the opposite side in the __________

Answer 41

decussate, medulla

Question 42

upper motor axons of the corticospinal tract synapse with the lower motor neurons in the ________ of spinal cord

Answer 42

ventral horn

Question 43

axons of lower motor neurons of the corticospinal tract innervate ________ muscles

Answer 43

voluntary

Question 44

what is the function of somatic motor nerves?

Answer 44

motor to skeletal muscles

Question 45

what is the function of somatic sensory nerves?

Answer 45

sensory from general cutaneous receptors and proprioceptors of skeletal muscles, tendons, joints, vision, and hearing

Question 46

what is the function of visceral motor nerves?

Answer 46

motor to smooth muscle, cardiac muscle, and glands

Question 47

what is the function of visceral sensory nerves?

Answer 47

sensory from receptors in viscera, taste, and olfaction

Question 48

T/F? Lampreys have both dorsal and ventral roots that do not unite to from the spinal nerve

Answer 48

true

Question 49

_________ rami from multiple adjacent spinal nerves combine to form _________ in gnathostomes

Answer 49

ventral, plexuses

Question 50

_________ rami of C __, __, __, form the _______ nerve that innervates the diapraghm

Answer 50

ventral, 3, 4, 5, phrenic

Question 51

what is a meninx?

Answer 51

single layer of meninges

Question 52

what are the meninges?

Answer 52

protective layer surrounding the brain and spinal cord

Question 53

fishes have ________ meninx

Answer 53

primitive

Question 54

amphibians, reptiles, and birds have 2 meninx layers the _________ and _________

Answer 54

dura mater, pia mater