Early Human Development

Question 1

What is the name for an immature egg cell?

Answer 1

Oocyte

Question 2

Name the outermost layer of oocytes (immature egg cell)

Answer 2

Corona radiata

Question 3

Name the second outermost layer of oocytes (immature egg cell)

Answer 3

Zona Pellucida

Question 4

Are sperm and egg cells haploid or diploid?

Answer 4

haploid

Question 5

What is the name of the stage where a sperm enters the oocyte? (immature egg cell)

Answer 5

Fertilisation

Question 6

Where does Fertilisation, cleavage of zygote and morula formation occur?

Answer 6

Fallopian Tube

Question 7

What is the name of the stage that happens 1 day after fertilisation?

Answer 7

Cleavage of Zygote (into 2 blastomere cells)

Question 8

What is the name of the stage that happens 4 days after fertilisation?

Answer 8

Formation of Morula

Question 9

What is the name of the stage that happens 5 days after fertilisation?

Answer 9

Formation of Blastocyst

Question 10

Name the three main components of a Blastocyst

Answer 10

Trophoblast, Blastocyst Cavity and Inner cell mass

Question 11

What is the name of the stage that happens 6 days after fertilisation?

Answer 11

Implantation

Question 12

Where does implantation occur?

Answer 12

In the endometrium of the uterus

Question 13

Name the Outer Germ Layer

Answer 13

Ectoderm (Blue)

Question 14

Name the Middle Germ Layer

Answer 14

Mesoderm (Red)

Question 15

Name the Inner Germ Layer

Answer 15

Endoderm (Yellow)

Question 16

Name the two cell types that the trophoblast differentiates into.

Answer 16

Syncytio-trophoblasts and Cyto-trophoblasts

Question 17

When the trophoblasts differentiates, which cell type is loosely packed and invades into the endometrium?

Answer 17

Syncytiotrophoblast

Question 18

blue layer of embryonic disc consists of

Answer 18

Hypoblasts

Question 19

yellow layer of embryonic disc consists of

Answer 19

Epiblasts

Question 20

The Hypoblast and Epiblast cells form the ______ embryonic disc.

Answer 20

bi-lamina

Question 21

Which cell type will eventually form a dome containing the amniotic cavity?

Answer 21

Epiblasts (blue)

Question 22

Which cell type eventually gives rise to the yolk sac?

Answer 22

Hypoblasts (yellow)

Question 23

What is the name of the small cavities that start to form within the Syncytiotrophoblast?

Answer 23

Lacunae Networks

Question 24

What is the provides a source of primordial germ cells?

Answer 24

Yolk sac

Question 25

What 2 types of cells the inner cell mass differentiate into?

Answer 25

Hypoblast and Epiblast

Question 26

Was is the first sign of Gastrulation?

Answer 26

Formation of Primitive Streak

Question 27

How is the Primitive Streak Formed?

Answer 27

Cells from top of Ectoderm burrow down below, this creates a cleft to form in the surface of Ectoderm

Question 28

Primitive streak starts from which end?

Answer 28

Tail End

Question 29

The Notochordal process is formed by cells burrowing through the ___________
and is part of the _______
layer.

Answer 29

Primitive Node and Mesoderm

Question 30

Ectodermal cells above the Notochordal process begin thickening, what is forming?

Answer 30

Neural Plate

Question 31

Describe the structure of Notochordal process

Answer 31

a hollow tube

Question 32

The process of the folding of the neural plate is called

Answer 32

Neurulation

Question 33

Eventually the Notochordal process forms a solid rod called

Answer 33

The Notochord

Question 34

A key function of the Notochord is to

Answer 34

Instruct neighbouring tissue

Question 35

The organ which instructs neurulation and formation of somites is the

Answer 35

Notochord

Question 36

The process of the folding of the neural plate forms the

Answer 36

Neural Tube

Question 37

Once formed, where is the Neural tube?

Answer 37

Seperate from Ectoderm Layer, Floating in Mesoderm

Question 38

What forms during the initial stage of neurulation?

Answer 38

Neural Grooves

Question 39

What forms during the Intermediate stage of neurulation?

Answer 39

Neural Folds

Question 40

How is the neural tube formed during neurulation?

Answer 40

The neural folds meet and fuse together.

Question 41

what type of cells migrates away from the Neural Tube once formed?

Answer 41

Neural Crest Cells

Question 42

Which type of cell eventually gives rise to melanocytes?

Answer 42

Neural Crest Cells

Question 43

Which type of cell eventually gives rise to nerves?

Answer 43

Neural Crest Cells