embryology Flashcards Preview

oral biology and clinical sciences 1 > embryology > Flashcards

Flashcards in embryology Deck (44)
Loading flashcards...
1

what is the name for a fertilised ovum?

zygote

2

what is a morula?

mass of cells

3

how many days in to a pregnancy is a morula formed?

4-6

4

what is a blastocyst?

hollow ball of cells with inner cell mass

5

when during pregnancy is a blastocyst formed?

6-10 days

6

how is the baby and mothers blood mixing prevented?

they are separated by a thin barrier known a the placenta

7

what is the placenta permeable to?

most molecules other than cells

8

when the embryonic inner cell mass forms 2 layers it is referred to?

bilaminar embryo

9

at how many days does the embryo become a bilaminar embryo?

10-12

10

what are the 2 layers of the bilarminar embryo called?

epiblast and hypoblast

11

what us the function of the epiblast in the bilaminar embryo?

gives rise to embryonic ectoderm

12

what us the function of the hypoblast in the bilaminar embryo?

participates in formation of endoderm and extra embryonic mesoderm

13

which twins are formed by splitting before fertilisation?

fraternal

14

which twins are formed from 1 egg?

identical

15

what is gastrulation of the embryo?

it forms an axis and 3 embryonic layers

16

what is the groove formed during gastrulation known as?

primitive streak

17

which 2 layers form the endoderm?

mesoderm and hypoblast

18

which cells form the mesoderm?

ectodermal cells

19

what is the name given to the early 3 layered embryo?

trilaminar embryo

20

what does the primitive streak develop into?

neural tube

21

when does the neural tube develop?

3-8 weeks

22

what is the name given to the development of organs from the 3 basic germ layers?

organogenesis

23

what is one of the 1st organs to form in an embryo?

CNS

24

what embryonic structure forms the CNS?

neural tube

25

what is the name of the 4th embryonic layer?

ectomesenchyme

26

which layer forms the ectomesenchyme?

ectoderm

27

which layer of the embryo is important for the development of the head?

ectomesenchyme

28

when in the development of an embryo does it start to take shape?

4 weeks

29

at which point in the development of a foetus does it have developed organs ?

9 weeks

30

when does an embryo become a foetus?

9 weeks