Lab2 Embryonic Development

Question 0

Embryology involves:

Answer 0

1- growth in cell number (thru mitosis)
2- differentiation of cellular specializations
3- morphogenesis to form functioning organ systems

Question 1

Embryology

Answer 1

Study of development of new individual

Question 2

Fertilization

Answer 2

Sperm+ egg= zygote

Question 3

Cleavage stages

Answer 3

Division of zygote into smaller and smaller cells form….

Question 4

Blastomeres

Answer 4

Identical cells

Question 5

Morula

Answer 5

• “mulberry”

- solid ball of cells (~32 cells)

Question 6

Blastula

Answer 6

• AKA blastocyte

- hollow ball of cells

Question 7

Trophoblast

Answer 7

Becomes chorion which will form fetal side of placenta

Question 8

Intercell mass(ICM)

Answer 8

will form embryo

Question 9

7 days old

Answer 9

Implantation of blastocyte with ICM next to uterine wall

Question 10

Thru day 14

Answer 10

Trophoblast secretes enzymes to allow burrowing into uterine blood supply

Question 11

Last cleavage stage

Answer 11

Uterine mucosa grows over implanted blastocyte

- uterine portions will form placenta

Question 12

Gastrulation

Answer 12

Invagination or enrolling if cells to form 3 germ layers :
1. Endoderm
2. Mesoderm
3. Ectoderm
Basic body plan of organism is now established

Question 13

Fetus

Answer 13

9th week of development thru birth

Question 14

Growth

Answer 14

Increase in size by cell division AKA mitosis and enlargement of individual cells.

Question 15

Ectoderm

Answer 15

Epidermis, nervous system, hair , nails

Question 16

Mesoderm

Answer 16

Skeleton, muscle , connective tissue , blood vessels , dermis of the skin , walls of digestive organs , urinary system

Question 17

Endoderm

Answer 17

Lining of digestive and respiratory tracts

Question 18

Placenta

Answer 18

Forms from uterine tissue and chorion( differentiated from trophoblast) with its chorionic villi

Question 19

Amnion

Answer 19

Forms from ICM to form a fluid- filled chamber around the embryo for protection

Question 20

Umbilical chord

Answer 20

Body stalk that connects embryo to placenta