Lecturio 2. Gastrulation and Trilaminar Embryo

Question 1

The process of gastrulation begins with (1)____

The epiblast involutes and creates (2)___

Answer 1

1. the bilaminar embryo.
2. the trilaminar embryo.

Question 2

Epiblast subdivides into ____ (3 categories)

Answer 2

ectoderm, endoderm and mesoderm

Question 3

Epiblast subdivides into ectoderm, endoderm and mesoderm

Set of three different germ cells that differentiate into __

Answer 3

specific and distinct tissues and not others

Question 4

Formation of the Primitive Streak

Bilaminar embryo becomes “polarized” by the ___, where the mouth will form

Answer 4

prechordal plate

Question 5

Formation of the Primitive Streak

Bilaminar embryo becomes “polarized” by the prechordal plate, where ___ will form

Answer 5

the mouth

Question 6

Formation of the Primitive Streak

____ becomes “polarized” by the prechordal plate, where the mouth will form

Answer 6

Bilaminar embryo

Question 7

Formation of the Primitive Streak

Bilaminar embryo becomes ___ by the prechordal plate, where the mouth will form

Answer 7

“polarized”

Question 8

Formation of the Primitive Streak

On the opposite side of the disc, epiblast cells collapse inward to create ____

Answer 8

the primitive streak.

Question 9

Formation of the Primitive Streak

On the opposite side of the disc,___collapse inward to create the primitive streak.

Answer 9

epiblast cells

Question 10

Formation of the Primitive Streak

The tip of the primitive streak is known as the (1)___, surrounded by the (2)___

Answer 10

1. primitive pit
2. primitive node.

Question 11

Formation of the Primitive Streak

IDENTIFY

Answer 11

Question 12

Migration through the Primitive Streak

→ IDENTIFY

Answer 12

Question 13

Migration through the Primitive Streak

Cells from the epiblast involute through the (1)____ to fill the space between the epiblast and hypoblast.

→ This middle layer is the (2)___.

Answer 13

1. primitive streak and pit
2. mesoderm

Question 14

Migration through the Primitive Streak

Cells from the epiblast involute through the primitive streak and pit to fill the space between ___

→ This middle layer is the mesoderm.

Answer 14

the epiblast and hypoblast.

Question 15

Migration through the Primitive Streak

Migrating epiblast cells also replace the hypoblast with a germ layer called the (1)___

→ epiblast layer remains but changes name to become the (2)____

Answer 15

1. endoderm
2. ectoderm

Question 16

Migration through the Primitive Streak

Migrating epiblast cells also replace ___ with a germ layer called the endoderm

→ epiblast layer remains but changes name to become the ectoderm

Answer 16

the hypoblast

Question 17

Migration through the Primitive Streak

Epiblast cells that move through the primitive pit and migrate straight toward the prechordal plate will become ___

Answer 17

the notochordal process.

Question 18

Migration through the Primitive Streak

Epiblast cells that move through the primitive pit and migrate straight toward ___ will become the notochordal process.

Answer 18

the prechordal plate

Question 19

Migration through the Primitive Streak

____ that move through the primitive pit and migrate straight toward ___ will become the notochordal process.

Answer 19

Migrating epiblast cells

Prechordal plate

Question 20

Migration through the Primitive Streak

Notochord cells cannot extend past the prechordal plate as the ectoderm and endoderm there are firmly adherent to each other.

→ This area is now called the ____

Answer 20

the oropharyngeal membrane.

Question 21

Migration through the Primitive Streak

Notochord cells cannot extend past ____ as the ectoderm and endoderm there are firmly adherent to each other. This area is now called the oropharyngeal membrane.

Answer 21

the prechordal plate

Question 22

Migration through the Primitive Streak

Notochord cells cannot extend past the prechordal plate as the ectoderm and endoderm there are firmly adherent to each other. This area is now called the oropharyngeal membrane.

→ A similar area on the other side of the primitive streak is ____

Answer 22

the cloacal membrane. (form the anus,….)

Question 23

Notochord

→ Identify

Answer 23

Question 24

Notochord

Migrating from the epiblast, ____ extends cranially towards the prechordal plate, a hollow notochordal canal is located within.

Answer 24

the notochordal process

Question 25

Notochord

Migrating from the epiblast, the notochordal process extends cranially towards ___,a hollow____ is located within.

Answer 25

• the prechordal plate
• notochordal canal

Question 26

Notochord

→ IDENTIFY?

Answer 26

Question 27

Gastrulation and the Trilaminar Embryo

→ The inferior side of the notochordal process and canal ruptures, creating _____

Answer 27

a notochordal plate.

Question 28

Gastrulation and the Trilaminar Embryo

→ The inferior side of ___ and canal ruptures, creating a notochordal plate.

Answer 28

the notochordal process

Question 29

Gastrulation and the Trilaminar Embryo

→ Identify

Answer 29

Question 30

Gastrulation and the Trilaminar Embryo

→ Identify

Answer 30

Question 31

Gastrulation and the Trilaminar Embryo

→ Identify

Answer 31

Question 32

Gastrulation and the Trilaminar Embryo

The plate then folds together within the mesoderm to form ___

Answer 32

notochord

Question 33

Gastrulation and the Trilaminar Embryo

The plate then folds together within the ___ to form the notochord.

Answer 33

mesoderm

Question 34

Intraembryonic Mesoderm

Notochord forms from cells, enter the mesoderm on (1)____

→ other cells’ fate is determined by their location as they pass through (2)___

Answer 34

1. the midline
2. the primitive streak

Question 35

Intraembryonic Mesoderm

Mesoderm migrate to the cranial and lateral to the prechordal plate to become ___

Answer 35

cardiogenic mesoderm

Question 36

Intraembryonic Mesoderm

Mesoderm migrate to the ___ (2 positions) to the prechordal plate to become cardiogenic mesoderm

Answer 36

1. cranial and lateral

Question 37

Intraembryonic Mesoderm

Mesoderm migrate to the cranial and lateral to ____ to become cardiogenic mesoderm

Answer 37

the prechordal plate

Question 38

Intraembryonic Mesoderm

Cells that enter even more caudally become ___ (4 things)

Answer 38

1. paraxial mesoderm
2. intermediate mesoderm
3. lateral plate mesoderm
4. extraembryonic mesoderm

Question 39

Intraembryonic Mesoderm

IDENTIFY

Answer 39

Question 40

Intraembryonic Mesoderm

IDENTIFY

Answer 40