Pt 741 Neuro Chap 5

Front 1

What are the 3 stages of human development and how long do each last?

Back 1

1. Preembryonic- from conception to 2 weeks
2. Embryonic- 2nd -end of 8th week
3. Fetal- end of 8th week until birth

Front 2

What 2 layers does the blastocyst turn into and during what period does this occur in?

Back 2

outer layer and inner cell mass

Front 3

During implantation what does the inner cell mass develop into it? and how many layers does it have?

Back 3

inner cell mass develops into the embryonic disc. it has two layers the ectoderm and endoderm. the mesoderm soon after forms between layers.

Front 4

At what stage are organs formed?

Back 4

during the embryonic

Front 5

What happens to the ectoderm during the embryonic period?

Back 5

becomes sensory organs, epidermis, and nervous system

Front 6

What happens to the endoderm during the embryonic period

Back 6

becomes the gut, liver, pancreas, respiratory system

Front 7

What happens to the mesoderm during the embryonic period?

Back 7

becomes the dermis, muscles, skeleton and excretory and circulatory functions

Front 8

What happens during the fetal period?

Back 8

myelination occurs

Front 9

What is the neural plate, what does it turn into, and at what time period does it do this?

Back 9

the neural plate is a longitudinal thickening of the ectoderm. from days 18-26 the edges of the tube fold to form a neural groove. usually around day 21 the tube is formed when the folds finally touch

Front 10

What is a neuropore?

Back 10

the open ends of the neural tube

Front 11

Which end of the neural tube closes first cervical or caudal?

Back 11

cervical

Front 12

cells next to the neurotube separate to form what? and what do they do?

Back 12

neural crest cells. they are cells that give rise to melanocytes, craniofacial cartilage and bone, smooth muscle, peripheral and enteric neurons and glia

Front 13

at what days does the superior neuropore close and the inferior close?

Back 13

the superior around day 27 and the inferior around day 30

Front 14

On day 26 the tube differentiates into two concentric rings what are they?

Back 14

Inner ring or mantle layer
Outer ring or marginal layer

Front 15

What does the inner ring or mantle layer develop into?

Back 15

gray matter

Front 16

What does the outer ring or marginal layer develop into?

Back 16

white matter axons and glial cells

Front 17

Where does the somite come from?

Back 17

the mesoderm that is adjacent to the neural tube

Front 18

What does the somite differentiate into?

Back 18

Dermatome, myotome and scleratome

Front 19

What does the sclerotome develop into?

Back 19

the vertebrae and the skull

Front 20

The mantle layer further develops into what 2 sections?

Back 20

Ventral and dorsal section

Front 21

The ventral section of the mantle is know as what and becomes what?

Back 21

it is known as the motor or basal plate, and axons from this region to innervate the myotome region

Front 22

The dorsal section of the mantle is also know as what? and becomes what?

Back 22

known as the association plate (alar plate) and becomes dorsal horn in mature spinal cord. this is also where interneurons are created

Front 23

The hindbrain is also know as what?

Back 23

rhombencephalon

Front 24

the midbrain is also known as what?

Back 24

mesencephalon

Front 25

the forebrain is also known as what?

Back 25

prosencephalon

Front 26

What makes up the hindbrain (rhombencphalon)?

Back 26

metencephlon (more superior and rostral)- pons, upper medulla, cerebellum, and 4th ventricles.
myelencephalon (more caudal portion)- lower medulla

Front 27

What makes up the midbrain (mesencephalon)?

Back 27

midbrain and cerebral aqueduct

Front 28

What makes up the forebrain (prosencephalon)?

Back 28

Diencephalon (posterior portion of forebrain)
Telencephalon (anterior portion of forebrain)

Front 29

What does the diencephalon consist of?

Back 29

thalmus, hypothalmus, subthalmus, and epithalmus

Front 30

What does the telencephalon consist of?

Back 30

cerebral hemispheres, basal ganglia, cerebral cortex, lateral ventricles.

Front 31

What is the arnold chiari malformation?

Back 31

it is a condition in which the cerebellum portion of the brain protrudes down into the spinal canal. It may be congenital, associated with other abnormalities including myelomeningocele, syringomyelia, spina bifida

Front 32

what is syringomyelia and what is it associated with?

Back 32

they are cysts of fluid within the spinal cord and is associated with arnold chiari

Front 33

What is spina bifida?

Back 33

it is a neural tube defect involving incomplete development of the brain, spinal cord, and or their protective coverings

Front 34

What are the 3 most common types of spina bifida?

Back 34

myelomeningocele- most severe
meningocele
occulta- most mild

Front 35

What is cranioschisis?

Back 35

failure of proper fusion of the cephalic part of the neural tube which leaves the brain and cranium open. the most extreme case results in anencephaly

Front 36

What holoprosencephaly?

Back 36

the failure of the prosencephalon to divide normally into 2 cerebral hemispheres (telencephalon) and may result in cyclopia

Front 37

What are the interventions used to treat spina bifida?

Back 37

surgery within 72 hrs and then a shunt to help with hydrocephalus and CSF flow

Front 38

when does myelination start and finish

Back 38

begins in 4th fetal month and are completed by the end of the third year of life