Pregnancy

What are the 3 main functions of estrogen in fertilization?

Thins cervical mucus, increases cilia, promotes uterine contractions

Steps of the acrosomal reaction

• Sperm approaches corona radiata using chemotaxis

• Proteolytic enzymes release from acrosome

• Enzymes digest path through outer layers

• Sperm binds to oocyte membrane and initiates fusion

What are the 2 mechanisms to prevent polyspermy?

Oocyte membrane block and cortical reaction

What forms around the embryo to provide protection and support for its growth?

amniotic sac

What chemical signals guide sperm to the egg during chemotaxis?

egg and surrounding cells

The chorion forms the outer layer of the

placenta

Which hormone stimulates the corpus luteum to continue producing progesterone and estrogen?

hCG

what is the normal birth position called?

vertex position

Progesterone levels rise steadily throughout pregnancy, while estrogen plateaus after the

first trimester

During cleavage, the zygote divides into a morula then a

blastocyst

Embryonic portion

Embryoblast -> Chorion || Chorionic villi with embryonic capillaries

Maternal portion

Decidua Basalis || Blood-filled lacunae (intervillous spaces)

What effect do estrogen and progesterone have on mammary glands during pregnancy?

prepare for lactation

Embryonic period

major organ systems develop

fetal period

organs mature further

what is the primary role of the acrosomal reaction?

Sperm penetration of egg

Through which structures does maternal blood flow into the placenta?

uterine arteries

Which cells become the main hormone manufacturers during pregnancy?

Syncytiotrophoblast