4 - embryogenesis, MRP and placentation

Question 1

zygote

Answer 1

fertilised egg

Question 2

early embryogenesis

Answer 2

embryo develops within zona pellucida
blastocyst hatches from the ZP

Question 3

what needs to be stopped in order to allow pregnancy

Answer 3

luteolytic signal

Question 4

what is maternal recognition of pregnancy

Answer 4

process by which an early conceptus signals its presence to the maternal system and prevents lysis of the corpus luteum thus entering a maternal milieu supportive of pregnancy continuation

Question 5

species specific mechanisms of MRP

Answer 5

inhibition of luteolytic factor - pigs, cow, sheep
secretion of luteotrophic factor - humans
no special mechanism - dogs and cats

Question 6

maintenance of progesterone - inhibition of luteolytic factor

Answer 6

regression of CL inhibited by blocking of PGF 2a signal
sheep and cows embryo produces interferon
pigs embryo produce oestradiol