Human development III

Question 1

in males the 20-week embryo until puberty, they have i

Answer 1

immature spermatogonia

Question 2

primary oocytes are arrested in

Answer 2

prophase of meiosis I

Question 3

in puberty primary oocytes can now develop into secondary oocytes and arrested in

Answer 3

metaphase of meiosis II

Question 4

Day 1-17

Answer 4

early embryonic development

Question 5

the three germ layers of the embryo are formed during the

Answer 5

third week of gastrulation

Question 6

when is implantation completed?

Answer 6

end of the second week after fertilization

Question 7

when is the bilaminer embryonic disc formed?

Answer 7

in implantation

Question 8

when is the late blastocyst is formed

Answer 8

day 12-14

Question 9

The zygote cleaves into _____ for 2-3 days without any ______ in overall size due to the presence of the ______

Answer 9

The zygote cleaves into blastomeres for 2-3 days without any increase in overall size due to the presence of the zona pellucida

Question 10

About day 3-4, it forms a _____ that consists of outer cells that form the ______ and _______

Answer 10

About day 3-4, it forms a morula that consists of outer cells that form the trophoblast and inner cell mass

Question 11

when is the late blastocyst formed?

Answer 11

during days 12-14, about a week after beginning of implantation at day 6-7

Question 12

Day:

eureka moment- membrane fusion/ICSI

Answer 12

-1

Question 13

Day:

fertilization complete- pronuclei fuse

Answer 13

0

Question 14

Day:

2-cell embryo- first embryonic cleavage

Answer 14

1

Question 15

Day:

4-cell embryo

Answer 15

2

Question 16

Day:

8- cell embryo

Answer 16

2.5- 3

Question 17

Day:

Morula- compaction

Answer 17

3-4

Question 18

Day:

Blastocyst- implantation period

Answer 18

5-14

Question 19

Day:

Gastrula

Answer 19

15-17

Question 20

Further cleavages form the ________ at day 4-5 and causes shedding of the _____ within a day or two. This permits the embryo to begin the implantation process

Answer 20

Further cleavages form the early blastocyst at day 4-5 and causes shedding of the Zona Pellucida within a day or two. This permits the embryo to begin the implantation process

Question 21

shedding of the zona pellucida

Answer 21

hatching

Question 22

blastococel forms

Answer 22

to break the zona pellucida

Question 23

blastocyst cavity

Answer 23

blastocel

Question 24

benefits of PGD testing of blastocyst vs blastomeres?

Answer 24

blastomere you can only remove 2 while in blastocyst you can remove multiple

Question 25

inner cell mass can make up a loss of ____ blastocyst cells

Answer 25

10-12

Question 26

At day 6, blastocyst attaches to the _______

Answer 26

endometrium

Question 27

epiblast and hypoblast are part of the

Answer 27

bilaminar disk of a developing embryo

Question 28

what secreted hCG?

Answer 28

blastocyst

Question 29

in the maternal circulation ensures survival of the corpus luteum and its continued production of progesterone

Answer 29

hCG

Question 30

measured in pregnancy tests

Answer 30

hCG

Question 31

endometrial stromal cells produce

Answer 31

PGE2

Question 32

blocks activation of T-cells and natural killer (NK) cells, thus providing immunologic immunity for the embryo

Answer 32

PGE2

Question 33

PGED during which days of implantation

Answer 33

Days 12-14

Question 34

all 3 cell layers come from the

Answer 34

epiblast

Question 35

layer that delaminates to allow endoderm formation “gets.out.of.the.way”

Answer 35

hypoblast

Question 36

gives rise to epiblast and hypoblast

Answer 36

ICM

Question 37

gives rise to placenta and most extra-emryonic tissues

Answer 37

trophoblasts

Question 38

overall early spontaneous abortion rate is

Answer 38

50%

Question 39

early losses keep the rate of congenital malformations at birth to

Answer 39

2-3%

Question 40

major causes of early spontaneous abortion from most common to least

Answer 40

(1) chromosomal abnormalities
(2) cleavage problems
(3) progesterone insufficiency

Question 41

TRUE or FALSE:

it is common to believe that infertility is caused by female issues.

Answer 41

FALSE!!!! both male and female at similar frequencies