15& 16- Neural Tube and Neural Crest Cells

Question 1

Ephrin A2

Answer 1

Soluble protein

Question 2

AphA2

Answer 2

Cell surface receptor for Ephrin A2`

Question 3

Semaphorin 3

Answer 3

Repels mechanoreceptor

Attracts NT3 responsive neurons

Question 4

Chemo-Attractants

Answer 4

Bindin of ephrins/netrins to axon growth cone cause F actin activation

Causes cycling between assembly/disassembly and creates microspikes

Question 5

Chemo Repellants

Answer 5

Slit
Semaphorins
Ephrins
Causes actin inactivation- inhibits microspikes

Question 6

Amphioxus NCC Genes

Answer 6

Snail
Pax 3/7 (pre migratory movement)
Zic/Dl x (neural border specifiers)

Question 7

NCC Migration- Permissive Factors

Answer 7

Fibronectin
Laminin

Part of ECM

Question 8

NCC Migration- Positive Chemotaxis

Answer 8

Neuregulins- part of NGF family

Question 9

NCC Migration- Inhibitory Factors

Answer 9

Ephrins

- Mainly repulsion

Question 10

NCC Migration- Negative Chemotaxis

Answer 10

Semaphorins
-Cell surface proteins
Act over small distances

Question 11

Cranial Placodes Form

Answer 11

Cranial nerves
lens of eye
Adenohypophysis
Sensory neurons

Question 12

Epidermal Placodes Form

Answer 12

Hair
Teeth
Feather/Scales
Mammary glands
Glands
Involve mesenchyme and ectoderm interactions

Question 13

Dermal Fibroblasts secrete

Answer 13

Fgf7,10
IGF
EGE
TGF-alpha
Stimulate proliferation

Question 14

Keratin Layers

Answer 14

Stratum corneum (dead skin)
Granular layer
Spinous layer

Question 15

Melanocytes have

Answer 15

MITF

Question 16

Cranial Cartilage Cells have

Answer 16

Sox9

Question 17

All NCC have

Answer 17

Sox 10