Lecture 2

Question 1

What becomes the embryo?

Answer 1

the epiblast

Question 2

What happens during the fetal period?

Answer 2

growth and maturation of existing organs

Question 3

What is a morula?

Answer 3

contains 16 cells

Question 4

Does the heart pump blood right after organogenesis?

Answer 4

No

Question 5

What are somites?

Answer 5

block-like structures of mesoderm

Question 6

What does the caudal neural tube become?

Answer 6

the spinal cord

Question 7

What is the cytotrophoblast?

Answer 7

individual cells that remain from the trophoblast

Question 8

What is apoptosis?

Answer 8

programmed cell death

Question 9

What is the mesoderm?

Answer 9

a layer of cells that fills in the space between the endoderm and ectoderm

Question 10

What is the pre-embryonic period?

Answer 10

weeks 1-2

Question 11

What does the inner cell mass of a blastocyst become?

Answer 11

embryo

Question 12

How is the neural groove formed?

Answer 12

tissues on the sides of the neural plate fold upward into neural folds

Question 13

What is the endoderm?

Answer 13

A sheet/layer of cells that displaces the hypoblast

Question 14

What is the syncytiotrophoblast?

Answer 14

Breaks down part of the trophoblast that attaches to the uterine wall

Question 15

When does differentiation of cell types begin to happen?

Answer 15

gastrulation

Question 16

What is the primitive streak?

Answer 16

an indentation along the dorsal surface of the epiblast that allows cells to descend through it to create two new layer of cells

Question 17

What is the prenatal period?

Answer 17

first 38 weeks of human development

Question 18

What is body folding?

Answer 18

the embryo begins to acquire a cylindrical shape essentially creating a tube called the primitive gut which is lined by the endoderm.

Question 19

What period does body folding happen

Answer 19

embryonic

Question 20

What is the fetal period?

Answer 20

weeks 9-38

Question 21

Does the heart beat after organogenesis?

Answer 21

Yes

Question 22

What does the trophoblast become?

Answer 22

chorionic membrane and the fetal portion of the placenta

Question 23

What is cleavage?

Answer 23

When a zygote undergoes five or six mitotic cell divisions

Question 24

What happens to the size/mass of the zygote as it goes through cleavage?

Answer 24

Stays the same

Question 25

How is the neural tube formed?

Answer 25

the neural folds converge

Question 26

What is the blastocoel?

Answer 26

fluid filled area in the blastocyst

Question 27

What is organogenesis?

Answer 27

The rudimentary structures of all tissues and organs are established

Question 28

What is an oocyte?

Answer 28

a female egg

Question 29

What is a zygote?

Answer 29

a fertilized egg, single cell

Question 30

What are the primary germ layers?

Answer 30

endoderm, mesoderm, ectoderm

Question 31

What is neurulation?

Answer 31

parts of the central nervous system develop from the ectoderm

Question 32

Where does neurulation happen?

Answer 32

the mesoderm

Question 33

What is the bilaminar disc?

Answer 33

comprised of the epiblast and hypoblast

Question 34

What is the chorion?

Answer 34

cell membrane that surrounds the embryo and fetus

Question 35

What period does gastrulation occur?

Answer 35

embryonic

Question 36

How is the brain formed?

Answer 36

the cephalic neural tube dilates

Question 37

How is the neural plate formed?

Answer 37

ectoderm cells thicken

Question 38

What is the embryonic period?

Answer 38

weeks 3-8

Question 39

What period do lim buds form?

Answer 39

embryonic

Question 40

What is the ectoderm?

Answer 40

cells of the epiblast that have not migrated through the primitive streak. makes ups the outside layer

Question 41

What period does organogenesis occur?

Answer 41

embryonic

Question 42

What period does the primitive streak form?

Answer 42

embryonic

Question 43

What does the mesoderm become?

Answer 43

skeleton, muscles, connective tissue, hear, blood vessels, kidneys

Question 44

What does the endoderm become?

Answer 44

gastrointestinal tract, respiratory tract, urinary tract

Question 45

When does the blastocyst come in contact with the uterine wall and adheres to it?

Answer 45

the end of the first week

Question 46

What is a blastocyst?

Answer 46

next step after morula. contains around 100 cells. starts to an inner cell mass and a trophoblast

Question 47

What is gastrulation?

Answer 47

results win the formation of the primary germ layers

Question 48

What does the neural tube become?

Answer 48

the brain and spinal cord

Question 49

What does the ectoderm become?

Answer 49

nervous system, sensory organs, epidermis, hair, nails

Question 50

What do somites differentiate into?

Answer 50

axial skeleton, skeletal muscle, dermis

Question 51

What period does neurulation occur?

Answer 51

embryonic

Question 52

Where do the epiblast and hypoblast come from?

Answer 52

the original inner cell mass