Development (section 1)

Question 0

What layer of the trilaminar state does the nervous system from from?

Answer 0

Ectoderm layer

Question 1

What day of gestation is the embryo in its trilaminar state?

Answer 1

16 days

Question 2

What four main structures does the mesoderm differentiate into?

Answer 2

Heart and Circulatory system
Muscle
Bone
Meninges

Question 3

What portion of the ectoderm forms the PNS and CNS?

Answer 3

Neural Plate

Question 4

What structure develops into the nucleus pulposis of the intervertebral discs

Answer 4

the notochord

Question 5

The rostral portion of the neural tube closes by what day?

Answer 5

Day 27

Question 6

What three things of the nervous system does the neural crest form?

Answer 6

Sensory ganglia of spinal and cranial nerves
Postganglionic neurons of ANS
Cells of adrenal medulla

Question 7

What structures does the endoderm differentiate into?

Answer 7

Viscera (digestive system, respiratory system)

Question 8

The caudal portion of the neural tube should close by what day?

Answer 8

Day 30

Question 9

Ectoderm differentiates into what structures?

Answer 9

Nervous system, Adrenal medulla and skin

Question 10

What are the 5 stages of Nervous System development

Answer 10

1. Neurulation
2. Cellular Proliferation
3. Neuronal migration
4. Cytodifferentiation and Axonal Elongation
5. Maturation of Synaptic Contacts and Refinement

Question 11

What are three congenital malformations of the nervous system?

Answer 11

Anencephaly
Spina Bifida
Arnold-Chiari malformation

Question 12

What are the three main categories of Spina bifida?

Answer 12

Spina bifida oculta
Spina bifida with meningocele
Spina bifida with myelomeningocele

Question 13

Which malformation of the nervous system is characterized by a failure of the caudal neurospore to close?

Answer 13

Spina bifida

Question 14

Which malformation is characterized by part of cerebellum and caudal brainstem herniate through the foramen magnum?

Answer 14

Arnold-Chiari malformation

Question 15

What is Spina bifida with myelomeningocele?

Answer 15

Spinal cord and meninges protrude in a saclike cavity on the back over the defect

Question 16

What is Anencephaly?

Answer 16

Failure of rostral neurospore to close

Question 17

What is characterized by having one or more vertebrae malformed and covered by a layer of skin?

Answer 17

Spina bifida oculta

Question 18

What is characterized by having the Meninges protrude in a saclike cavity on the back over the defect.

Answer 18

Spina bifida with meningocele?

Question 19

What is characterized by failure of rostral neurospore to close?

Answer 19

Anencephaly

Question 20

What is characterized by a spinal cord and meninges protruding in a saclike cavity on the back over the defect?

Answer 20

Spina bifida with myelomeningocele

Question 21

Tissue of the neural plate and neural tube can be divided into what three functional layers?

Answer 21

Germinal Zone (Ventricular Zone)
Intermediate Zone
Marginal Zone (cortical plate)

Question 22

What layer of the neural tube is the innermost layer

Answer 22

Germinal Zone (ventricular zone)

Question 23

2 classification of cells in germinal layer

Answer 23

Neuroblasts

Glioblasts

Question 24

How do the neuroblasts migrate out of the germinal zone

Answer 24

They use the glioblasts to help them migrate out

Question 25

Drugs, radiation and genetic mutations may cause what?

Answer 25

Interference with the process of neuron migration

Question 26

What type of malformation reveals pockets of misplaced neurons?

Answer 26

Childhood epilepsy

Question 27

What is radial migration?

Answer 27

Neuronal precursors uses fibers from radial glial cells and their own axons to migrate from germinal zone to brain's outer layers (int. zone and marginal zone).

Question 28

How do glial cells help neurons find correct pathway during migration?

Answer 28

They secrete chemical attractants

Question 29

How are neurons able to migrate on glial cells

Answer 29

Glial cells secrete chemical attractants and neurons have adhesion molecules on their surface that enable them to bind to glial fibers

Question 30

What directions can neurons travel as they migrate?

Answer 30

They can travel radially and tangential (perpendicular). Some neurons migrate in a tangential directions moving from one radial glia to another.

Question 31

What separates the dorsal from ventral neurons during formation of the spinal cord?

Answer 31

Sulcus limitans

Question 32

Alar plate contains what type of neurons?

Answer 32

Sensory and association neurons

Question 33

Can neurons in the alar plate migrate into the basal plate?

Answer 33

No, neurons that are born on one side of the sulcus limitans cannot cross over to the other side.

Question 34

What neurons are found in the basal plate?

Answer 34

Motor neurons

Question 35

Neurons found in Alar plate?

Answer 35

Sensory and association neurons

Question 36

Motor neurons found where during spinal cord migration?

Answer 36

Basal plate

Question 37

Three steps of axon elongation

Answer 37

Growth cone Pathfinding Synapse formation

Question 38

Axon finds its proper target through what four processes?

Answer 38

Contact repulsion Chemo repulsion Contact attraction Chemo attraction

Question 39

What is the growth cone?

Answer 39

Enlargement on the distal end of a growing axon

Question 40

What are the fingerlike extensions on the growth cone called?

Answer 40

filapodia and lamellipodia

Question 41

Why does the axons and neurons need to be fine tuned or pruned?

Answer 41

Because there are more axons/neurons produced than needed resulting in large overlaps

Question 42

What three mechanisms help decide which axon stays and which goes?

Answer 42

Activity (use it or lose it) Neurotrophic factors Intrinsic genetic programs