embryonic development by timeline Flashcards Preview

Step 1 > embryonic development by timeline > Flashcards

Flashcards in embryonic development by timeline Deck (16):
1

Day 0

fertilization by sperm

2

Day 3

morula

3

Day 5

blastocyst

4

Day 6

implantation

5

Within 1 week

hCG secretion ebgins after implantation

6

Within 2 week

bilaminar disk (epiblast and hypoblast)

7

Within 3 weeks

gastrulation forms trilaminar disk. Beginning of primitive streak, notochord forms

8

within 3-8 weeks

neural tube formation, organogenesis, high susceptibility to teratogens

9

Week 4

heart begins to beat, upper and lower limb buds begin to form

10

Week 8

fetal movement, fetus looks like a baby

11

week 10

genitalia have differentiated by sex

12

dizygotic

dichorionic, diamniotic

13

0-4 days

dichorionic, diamniotic (fused or separate placenta possible)

14

4-8 days (morula)

monochorionic, diamniotic

15

8-12 days (blastocyst)

monochorionic, monoamniotic

16

>13 days (embryonic disks form

monochorionic, monoamniotic conjoined twins)