Embryology 2.0

Question 1

conceptus

Answer 1

fertilisation to the end of week 3

Question 2

embryo

Answer 2

fertilisation (or week 4) to week 8

Question 3

foetus

Answer 3

week 9 to birth

Question 4

7 phases of embryogenesis

Answer 4

1. gametogenesis
2. fertilisation
3. cleavage
4. gastrulation
5. formation of body plan
6. organogenesis
7. foetal period

Question 5

two potential processes in gametogenesis

Answer 5

oogenesis

spermatogenesis

Question 6

describe the process of fertilisation

Answer 6

sperm binds to the zone pellucida and acrosomal enzymes are released from the sperm allowing it to digest its way into the egg, membranes fuse and the sperm enters the egg

Question 7

describe cleavage (days 1-4)

Answer 7

period of rapid cell division with compaction producing the morula and then blastocyst

Question 8

describe gastrulation (week 3)

Answer 8

formation of the germ layers (ectoderm, mesoderm and endoderm), beginning marked by the primitive streak in epiblasts

Question 9

normal implantation sites

Answer 9

middle or upper dorsal uterine wall

Question 10

what day is implantation complete?

Answer 10

day 9

Question 11

what are epiblasts associated with?

Answer 11

amniotic cavity

Question 12

what are the hypoblasts associated with?

Answer 12

yolk sac

Question 13

what does the ectoderm produce?

Answer 13

skin and nervous system

Question 14

three layers of the mesoderm

Answer 14

paraxial
intermediate
lateral

Question 15

what does the lateral mesoderm split into?

Answer 15

somatic

visceral

Question 16

what does the paraxial mesoderm produce?

Answer 16

axial skeleton

voluntary muscles

Question 17

what does the intermediate mesoderm form?

Answer 17

urogenital system

Question 18

what does the lateral somatic mesoderm form?

Answer 18

lining of body wall and most of dermis

Question 19

what does the lateral visceral mesoderm become?

Answer 19

lining of gut tube, respirator tract, bladder and urethra