Week 3

Front 1

what are the main events of week 3

Back 1

primitive streak- which gives rise to 3 germ layers

notochord, neural tube and somites

Front 2

what is gastrulation

Back 2

process by which the bilaminar embryonic disc is converted to a trilaminar embryonic disc

- occurs via the formation of the primitive streak

Front 3

epiblast is renamed as what?

Back 3

ectoderm

Front 4

what does the ectoderm consist of?

Back 4

skin, CNS, PNS, eyes, internal ear, neural crest face, (bones and connective tissue of the face and part of skull)

Front 5

what does the mesoderm consist of ?

Back 5

bones, connective tissue, urogenital system, cardiovascular system

Front 6

what does the endoderm consist of ?

Back 6

gut and gut derivatives (liver, pancreas, lungs, etc), epithelial linings, respiratory and digestive tracts

Front 7

the primitive streak regresses at the end of the__ week and if it doesnt this is called ?

Back 7

4th, sacrococcygeal teratoma - benign tumors

Front 8

__ grows cranially from the primitive pit to the prechordal plate

Back 8

notochordal process

Front 9

what 3 things does the notochord do?

Back 9

1. axis for the development of the axial skeleton

2. induces the formation of the bodies of the vertebrae

3.invertebral discs

4. induces the overlying ectoderm to form the neural plate

Front 10

what forms the neural plate?

Back 10

thickening of ectoderm

Front 11

on what day does the neural plate invaginate to form the __ with ___ on either sidE?

Back 11

18, nerual groove, neural folds

Front 12

the anterior neurospore closes day __

posterior neurospore closes day__

Back 12

25

27

Front 13

neural crest cells form from what?

Back 13

margins or folds

Front 14

what are somites and what do they give rise to (3)?

Back 14

paraxial mesoderm forms paired cube shaped blocks (days 20-30)

vertebrae (sclerotomes)

muscles of neck, body wall and limbs (myotomes)

dermis of scalp, neck and trunk (dermatomes)

Front 15

__ plus __ form the somatopleure (body wall)

Back 15

intraembryonic somatic mesoderm+ectoderm

Front 16

__ + __ = splanchnopleure (gut wall)

Back 16

intraembryonic splanchnic mesoderm + endoderm

Front 17

intraembryonic cavity will give rise to what other 3 cavities?

Back 17

pericardial, pleural and peritoneal

Front 18

the formation of new vascular channels by assembly of individual cell precursors called angioblasts is called ?

Back 18

Vasculogenesis

Front 19

the formation of new vessels by budding and branching from preexistig vessels is called?

Back 19

angiogenesis