Week 8 - Embryonic development and Pregnancy

Identify A

Morula

Identify B

Blastocyst

Identify C

Inner Cell Mass

Identify D

Trophectoderm

Identify E

Blastocoele

What does the crown-rump length growth curve suggest about energy requirements during the first stages of gestation?

Low requirement prior to attachment then high energy needed during logarithmic (exponential) growth phase

What are the functions of the 4 placental membranes?

protection, nutrition, respiration, hormone production

What is the pregnancy recognition signal for cows/sheep/goats?

Interferon Tau

What is the pregnancy recognition signal for pigs?

estrogen

What is the pregnancy recognition signal for horses?

not known, most likely movement of embryo

What is the pregnancy recognition signal for mice?

Prolactin

What is the pregnancy recognition signal for humans?

Human Chorionic Gonadotropin

Which type of placenta is most efficient? Why?

Discoid - fewer layers of tissue for blood to pass through from mother to fetus

Which type of placenta is least efficient? Why?

Cotyledonary (or diffuse) - more layers of tissue that nutrients have to travel between maternal blood and fetal blood

The rugae is what?

Maternal side of the placenta in pigs

The areola is what?

Fetal side of the placenta in pigs

The cotyledon is what?

Fetal side of the placenta in cows

The caruncle is what?

Maternal side of the placenta in cows

What placenta do horses and pigs have?

Diffuse

What placenta do ruminants have?

Cotyledonary

What placenta do carnivores have?

Zonary

What placenta do primates and rodents have?

Discoid