Mechanisms in Gastrulation

Question 1

In amphibians (frog),

______ indicates the future dorsal side

Answer 1

grey crescent

Question 2

in amphibians (frog)

the point of entry is the future belly/ ______ side

Answer 2

ventral

Question 3

in amphibians (frog)

the ________ is the future posterior side, usually marking the ____

Answer 3

blastopore, anal area

Question 4

in amphibians (frog)

__________: fertilization/sperm entry

Answer 4

dorsoventral axis

Question 5

in amphibians (frog)

__________: point of invagination and involution

Answer 5

anteroposterior axis

Question 6

in amphibians (frog)

_______: biomarker to developmental stages

Answer 6

Grey crescent

Question 7

in amphibians (frog)

_______: entry of sperm

Answer 7

ventral side

Question 8

in birds

determination of ______ is through the difference in pH and charge - and + charge in the subgerminal space due to Na+ and relatively low pH induces the ventral side

Answer 8

dorsoventral axis

Question 9

in birds

determination of dorsoventral axis is __________ due to Na+ and relatively low pH induces the ventral side

Answer 9

through the difference in pH and charge - and + charge in the subgerminal space

Question 10

in birds

determination of dorsoventral axis is through the difference in pH and charge - and + charge in the subgerminal space due to _______

Answer 10

Na+ and relatively low pH induces the ventral side

Question 11

in birds,

_________ is determined by the hypoblast, where it starts to form is the posterior side

Answer 11

anteroposterior axis

Question 12

in birds,

anteroposterior axis is determined by the _____, where it starts to form is the posterior side

Answer 12

hypoblast

Question 13

in birds,

anteroposterior axis is determined by the hypoblast, where it starts to form is the _______side

Answer 13

posterior

Question 14

Ingression in birds is made possible by coating of_________ on the cell surface

Answer 14

hyaluronic acid

Question 15

during ingression in birds, only _______ cells in the epiblast can ingress

Answer 15

HNK+ (sulfated glucuronic acid)

Question 16

during ingression in birds, only HNK+ (sulfated glucuronic acid) cells in the epiblast can ______

Answer 16

ingress

Question 17

during ingression in birds, only HNK+ (sulfated glucuronic acid) cells in the _______ can ingress

Answer 17

epiblast

Question 18

During ingression in birds, cells change from the _______ unto ______ then into ______

Answer 18

epithelium, bottle-shaped cells, mesenchymal cells

Question 19

in birds
_________ is the delamination of hypoblast

Answer 19

Anteroposterior axis

Question 20

in birds,

______ is formed through the difference in pH

Answer 20

Dorsoventral

Question 21

during dorsoventral formation,
stretching of the chordamesoderm and primitive streak anteroposteriad is due to _________ caused by cells rapidly dividing, intercalating, and spreading

Answer 21

convergent extension

Question 22

during dorsoventral formation,
stretching of the chordamesoderm and primitive streak anteroposteriad is due to convergent extension caused by cells ______, _________, and _________

Answer 22

rapidly dividing, intercalating, and spreading

Question 23

in birds

after the stretching of the chordamesoderm and primitive extension anteroposteriad

• ______will become the notochord

Answer 23

chordamesoderm

Question 24

in birds

after the stretching of the chordamesoderm and primitive extension anteroposteriad

• chordamesoderm will become the notochord
• chordamesoderm ingress in the ______

Answer 24

Hensen’s node

Question 25

in birds, during dorsoventral formation, migrating cells interact with each other through ________

Answer 25

cell adhesion molecules (CAM)

Question 26

what are the three cell adhesion molecules?

Answer 26

cadherins, CAMs of the immunoglobulin superfamily, cells that associate with substance of the extracellular matrix (fibronectin, laminin)

Question 27

true or false cadherins are permanent structures

Answer 27

False (not permanent)

Question 28

the four CAMs of the immunoglobulin superfamily

Answer 28

1.N-CAMs 2. integrins 3. lectins and selectins 4. glycosyltransferases

Question 29

Cells associate with substance of the extracellular matrix such as _______, ________

Answer 29

fibronectin, laminin

Question 30

cadherins are not permanent structures. How do they function?

Answer 30

they mediate binding of non-junctional complexes