Embryology

Question 1

What are teratogens

Answer 1

compounds toxic to embryonic/fetal development

Question 2

How to embryonic cells grow?

Answer 2

1. number of cells
2. size of cells
3. amount of extracellular matrix

(caused by morphogenesis, differentiation, patterning)

Question 3

what is morphogenesis?

Answer 3

any change in shape of individual cells or tissues

Question 4

What is differentiation?

Answer 4

process by which an undifferentiated cell becomes committed to a particular cell lineage.
(becomes blood cells, heart cells, etc.)

Question 5

What is patterning?

Answer 5

establishment of correct orientation or position of preprogrammed subgroups of cells to each other or surrounding tissues.

Usually precedes differentiation or morphogenesis.

Question 6

What is apoptosis?

Answer 6

programmed cell death

Question 7

Fusion of gametes is called a

Answer 7

zygote

Question 8

What is the process called when a zygote undergoes mitotic divisions

Answer 8

cleavage

Question 9

What does the first cleavage produce?

Answer 9

a blastomere
(2 daughter cells)

Question 10

What results of the repeated division of blastomeres?

Answer 10

a morula

Question 11

After the morula compacts, what are the superficial cells called

Answer 11

the trophoblast

Question 12

what does the trophoblast become

Answer 12

extra-embryonic membranes

Question 13

When fluid accumulates, what is the embryo called?

Answer 13

a blastocyst

Question 14

Blastulation results in the formation of…

Answer 14

inner cell mass, trophectoderm, epiblast, and hypoblast

Question 15

The epiblast and the inner cell mass become the

Answer 15

embryo

Question 16

the hypoblast and the trophectoderm

Answer 16

extra-embryonic membranes

Question 17

What is gastrulation?

Answer 17

process of germ layer formation

Question 18

What are the 3 layers of the blastula (after it developed from a single layer)

Answer 18

outer ectoderm
middle mesoderm
inner endoderm

Question 19

What does the ectoderm develop into

Answer 19

epidermis (skin) and neural tissue

Question 20

What does the endoderm become?

Answer 20

lining of gastrointestinal and respiratory tracts

Question 21

What does the mesoderm become?

Answer 21

urogenital, circulatory, and musculoskeletal system

Question 22

What is the primitive streak?

Answer 22

accumulation of epiblast cells on the posterior portion of the embryonic disc. This forms the primitive streak

Question 23

Why is cell signaling important for embryology?

Answer 23

signaling is responsible for cell division, differentiation, etc.

signaling mechanisms must be precise, reproducible and consistent to properly develop

Question 24

What is induction?

Answer 24

Induction is a developmental process in which the fate of a group of cells is determined by interactions with another group of cells.

Depends on: competence and microenvironment.

2 types: Instructive and permissive

Question 25

What is instructive induction?

Answer 25

a cell receives a signal and follows a particular developmental pathway. Without the signal, the cell follows a different pathway

Question 26

What is permissive induction?

Answer 26

a cell is already going down a pathway but needs additional signals to continue on that path.

Question 27

the notochord signals to the _____ (dorsal to the it) to create the ____ _____

Answer 27

ectoderm, neural plate

Question 28

the neural plate creates the _______ which turns into the _____

Answer 28

neural groove, neural tube

Question 29

the neural tube creates the _____ and the neural crest cells create the _____

Answer 29

CNS, PNS

the nervous system is the first system :)

Question 30

When is embryonic development most vulnerable to teratogens?

Answer 30

early-middle when the organs are developing