Central Nervous System ( Finals )

Question 1

gives rise to neurons, glial cells (astrocytes and oligodendrocytes), and ependymal cells

Answer 1

Neuroepithelium

Question 2

cells have processes which contact the inner and outer surfaces of the neural tube; they undergo mitotic division

Answer 2

Neuroepithelial

Question 3

loses contact with surfaces of the neural tube and migrate toward the center of the neural tubewall

Answer 3

Neuroblasts and glioblasts

Question 4

are derived from mesoderm associated with invading blood vessels

Answer 4

Microglial

Question 5

Accumulated neuroblasts and glioblasts form what layer?, a zone of high cell density in the wall of the nerual tube

Answer 5

mantle layer

Question 6

that remain lining the neural cavity are designated as what cells?

Answer 6

ependymal cells

Question 7

that remain lining the neural cavity are designated ependymal cells; they form what kind of layer?

Answer 7

ependymal layer

Question 8

Surrounding the mantle layer, a cell- sparse zone where axons of neurons and some glial cells are present is designated the?

Answer 8

marginal layer

Question 9

The mantle layer becomes what matter?

Answer 9

gray matter

Question 10

The mantle layer becomes gray matter and the marginal layer becomes what matter of the CNS?

Answer 10

white matter

Question 11

The lateral wall of the neural tube is divided into?

Answer 11

two regions (plates)

Question 12

A bilateral indentation evident in the neural cavity called?

Answer 12

sulcus limitans

Question 13

A bilateral indentation evident in the neural cavity (the sulcus limitans) serves as a landmark to divide each lateral wall into an?

Answer 13

alar plate (dorsal) and a basal plate (ventral)

Question 14

Midline regions dorsal and ventral to the neural cavity constitute, respectively, what plates?

Answer 14

roof plate and the floor plate

Question 15

This plate contains efferent neurons that send axons into the PNS

Answer 15

basal plate

Question 16

This plate contains neurons that receive input from the PNS.

Answer 16

alar plate

Question 17

Generally, neurons are incapable of ?, so all neurons must be formed during nervous system development

Answer 17

cell division

Question 18

Generally, neurons are incapable of cell division, so all neurons must be formed during nervous system development. However, in hippocampus and olfactory bulb, what persist and can give rise to a small number of new neurons postnatally.

Answer 18

some stem cells or neuroblasts

Question 19

is generally long and often encased in a myelin sheath formed by glial cells.

Answer 19

axon

Question 20

Unstained myelin has what color?

Answer 20

white color

Question 21

This matter refers to CNS regions that have a high density of myelinated axons

Answer 21

White matter

Question 22

This matter has sparse myelinated axons and generally a high density of neuron cell bodies

Answer 22

Gray matter

Question 23

removing excess material to achieve a desired effect

Answer 23

Sculpting

Question 24

To ensure that all targets get sufficient innervation, what development produces an excessive number of neurons along with a profuse, random growth of neuronal processes?

Answer 24

initial neural development

Question 25

What will degenerate and disappear if they fail to contact an appropriate target due to insufficient neurotrophic molecules?

Answer 25

Neuron

Question 26

What molecules are released by target cells to nurture neurons?

Answer 26

Neurotrophic molecules

Question 27

Initially, individual neurons innervate an excessive number of muscle fibers and individual muscle fibers are innervated by a number motor neurons

Answer 27

Neuromuscular Innervation

Question 28

What neurons will innervate only,about 10% of their initial muscle fibers and individual muscle fibers will retain only a single neuromuscular synapse

Answer 28

motor neurons

Question 29

What released more neurotransmitter per terminal branch

Answer 29

survivors (winners)

Question 30

In human prefrontal cortex, synaptic density peaks during what year of age (80K/neuron)?

Answer 30

first year

Question 31

In the human prefrontal cortex, synaptic density peaks during the first year of life at approximately 80,000 synapses per neuron. What stage of life has half that synaptic density?

Answer 31

Adult

Question 32

cranial end of the neural tube forms how many vesicles?

Answer 32

three vesicles

Question 33

cranial end of the neural tube forms three vesicles (enlargements) that further divide into how many primary divisions of the brain?

Answer 33

five primary divisions

Question 34

Caudal to the brain the neural tube develops into?

Answer 34

spinal cord

Question 35

What flexure occurs at the level of the midbrain

Answer 35

midbrain flexure

Question 36

What flexure appears at the junction between the brain and spinal cord (it persists slightly in domestic animals)?

Answer 36

cervical flexure

Question 37

What flexure is concave dorsally (the other flexures are concave ventrally)?

Answer 37

pontine flexure

Question 38

What becomes central canal lined by ependymal cells

Answer 38

neural cavity

Question 39

growth of alar and basal plates, but not roof and floor plates, results in symmetrical right and left halves separated by what fissure or septum?

Answer 39

ventral median fissure and a dorsal median fissure (or septum)

Question 40

the mantle layer develops into what matter?

Answer 40

gray matter

Question 41

the marginal layer becomes what matter?

Answer 41

white matter

Question 42

alar plates move laterally and the cavity of the neural tube expands dorsally forming a?

Answer 42

fourth ventricle

Question 43

the roof of the fourth ventricle (roof plate) is stretched and reduced to a layer of ependymal cells covered by?

Answer 43

pia mater

Question 44

the roof of the fourth ventricle (roof plate) is stretched and reduced to a layer of ependymal cells covered by pia mater and what develops bilaterally in the roof of the ventricle and secretes cerebrospinal fluid

Answer 44

choroid plexus

Question 45

What plate is positioned medial to the alar plate alar plate and ventral to the fourth ventricle;

Answer 45

basal plate

Question 46

white and gray matter becomes what? In fourth ventricle?

Answer 46

intermixed

Question 47

Adult cerebellum features surface gray matter, called?

Answer 47

cerebellar cortex

Question 48

Adult cerebellum features surface gray matter, called cerebellar cortex, and three pair of ? located deep within the cerebellar white matter

Answer 48

cerebellar nuclei

Question 49

What are the first evidence of cerebellar development; the lips are expansions of the alar plate into the roof plate

Answer 49

bilateral rhombic lips

Question 50

rhombic lips merge medially, forming a?

Answer 50

midline isthmus

Question 51

deep cells migrate (pass the superficial cells) toward the cerebellar surface and becomes what cell of the cerebellar cortex?

Answer 51

Purkinje cells

Question 52

neurons of the superficial layer migrate deeply and becomes?

Answer 52

cerebellar nuclei

Question 53

neuroblasts located laterally in the rhombic lip migrate along the outer surface of the cerebellum, forming an?

Answer 53

external germinal layer

Question 54

populations past one another allows connections to be established between neurons of the respective populations

Answer 54

Migration of neuron

Question 55

Neurons that fail to connect are destined to?

Answer 55

degenerate

Question 56

the neural cavity of the midbrain becomes?

Answer 56

mesencephalic aqueduct

Question 57

alar plates of midbrain form two pairs of dorsal bulges which become?

Answer 57

rostral and caudal colliculi

Question 58

the basal plate of midbrain gives rise to what Cranial Nerves which innervate muscles that move the eyes?

Answer 58

oculomotor (III) and trochlear (IV) nerves

Question 59

midbrain is the rostral extent of what plate?

Answer 59

basal plate

Question 60

What is the part of brain that are derived entirely from alar plate

Answer 60

Forebrain

Question 61

the neural cavity expands dorsoventrally and becomes the narrow?

Answer 61

third ventricle

Question 62

1. What is stretched? and 2. what develop bilaterally in the roof of the third ventricle and secrete cerebrospinal fluid

Answer 62

1. roof plate 2. choroid plexuses

Question 63

the floor of the third ventricle gives rise to the?

Answer 63

neurohypophysis

Question 64

the mantle layer of the diencephalon gives rise to?

Answer 64

thalamus and hypothalamus

Question 65

What nerve develops from an outgrowth of the wall of the diencephalon?

Answer 65

optic nerve

Question 66

bilateral hollow outgrowths become?

Answer 66

right and left cerebral hemispheres

Question 67

bilateral hollow outgrowths become right and left cerebral hemispheres; the cavity of each outgrowth forms what ventricle that communicates with the third ventricle via an interventricular foramen?

Answer 67

lateral ventricle

Question 68

at the midline, the rostral end of the telencephalon forms the? of the third ventricle

Answer 68

rostral wall

Question 69

the mantle layer surrounding the lateral ventricle in each hemisphere gives rise to?

Answer 69

basal nuclei and cerebral cortex

Question 70

cellular migrations that form cerebral cortex: from the mantle layer, cells migrate radially to the surface of the ?, guided by glial cells that extend from the ventricular surface to the outer surface of the cerebral wall

Answer 70

cerebral hemisphere

Question 71

What wave (which becomes the deepest layer of cortex) migrates to the surface of the cortex?

Answer 71

first wave

Question 72

What wave (which forms the next deepest layer of cortex) migrates to the cortical surface, passing through first wave neurons which are displaced to a deeper position?

Answer 72

second wave

Question 73

are established within the cerebral cortex as waves of newly arriving neurons migrate through populations of neurons that arrived earlier

Answer 73

Cell connections