Representative Gastrulation Patterns in Bird/Avian (Megalecithal)

Question 1

Megalecithal egg gastrulation

it refers to the point where the blastodisc is sitting on top of yolk

Answer 1

area opaca

Question 2

it is where first blood vessels of the organisms form

Answer 2

area opaca

Question 3

it is an area where light can penetrate and
where the embryo forms

Answer 3

area pellucida

Question 4

Gastrulation in avian egg

true or false
In area pellucida, cells divide and divide than they were spread to opposite sides which corresponds to the future anterior side

Answer 4

False (spreads to one side, future posterior side)

Question 5

in avian egg

_______ and whole cells _________ because the cells are dividing

Answer 5

Primitive streak, elongates

Question 6

_________: like a mountain of cells; will form a groove: moving cells will form the mesoderm and endoderm

Answer 6

Primitive streak

Question 7

___________ gives rise to all parts of the organism

Answer 7

Epiblast

Question 8

all cells that will ingress will form the _________

Answer 8

Hensen’s node

Question 9

What is the order of ingression?

Answer 9

1. pharyngeal cells of foregut
2. prechordal plate/ head mesoderm
3. chordamesoderm that becomes the notochord

Question 10

________ cells of foregut

Answer 10

pharyngeal

Question 11

prechordal plate/________

Answer 11

head mesoderm

Question 12

what becomes the notochord?

Answer 12

chordamesoderm

Question 13

Why is it that the notochord is the last to form?

Answer 13

because Notochord underlies the neural ectoderm

Question 14

All the rest of the mesoderm and endoderm will _________ through the lateral areas of the primitive streak

Answer 14

ingress

Question 15

In frog, all the rest of the mesoderm and the endoderm will ________through the lateral areas of the primitive streak

Answer 15

involute

Question 16

in frog, it is the elongated blastopore

Answer 16

Primitive streak

Question 17

In frog, _______ is like a dorsal lip

Answer 17

Hensen’s node

Question 18

Why is it that there is more movements in the avian egg than the frog egg?

Answer 18

because avian eggs, tho have larger yolk, have separated yolk, while frog’s egg is massive and unified (?)

Question 19

in frog, primitive streak will gradually _______: will ______ fully

Answer 19

shorten, regress

Question 20

In frog,
where the first ________ fell, it indicates the future _____ side of the embryo

Answer 20

hypoblast, posterior side

Question 21

In frog, primitive streak forms in the ________

Answer 21

epiblast

Question 22

in frog,
Hypoblast will be displaced anteriorly and form the _________

Answer 22

germinal placenta

Question 23

_____________: will form the PGCs that will eventually go to the _______

Answer 23

Germ crescent, genital ridge