A & P II - Lab 13 - Fertilization, Embryology & Pregnancy

Fertilization

Sperm’s chromosome combine with an egg to form a zygote

Zygote

First cell of an individual

Clevage

Cells that are copying but not dividing

Gastrulation

When the embryo forms the 3 primary germ layers

Unfertilized eggs

Large dark, spherical cells

2 Cell stage

2 cells

4 Cell Stage

4 cells

8 cell stage

two sets of 4 cells overlapping

16 cell stage

Large clump of cells

32 cell stage (morula)

Darker, larger clump of cells

Gastrula

Larger cell

Archenteron

Large rectangle sticking in the middle of the cell

Blastocyst

Day 4-5

Floats in uterus & internally accumulates fluid, contains trophoblast cells

Embryoblast

Inner cell mass in blastocyst

Trophoblast

Flattened cell around the outside of the cell

Chorionic Villi

Space of capillaries that connect to mother’s blood supply

Amnion

FLuid filled pocket surrounding and buffering the embryo

Chorion

Outermost fetal membrane which helps form the placenta

Yolk Sac

Early source of energy before placenta will develop into the fut

Allantois

Develops into umbilical cord, from a stalk-like projection

Day 1&2

Blastomeres

Day 3&4

Morulas

Day 6

Blastocyst

Day 7-10

Implantation

Day 9

Implanted

Day 16

Embryo

Ectoederm

Nervous System & Epidermis

Mesoderm

Heart Circulatory, Bone, Cartilage & Kidneys

Endoderm

Liver, Pancreas, Lungs, Thyroid, Gallbladder

Ovary

Yellow-tube that connects to fimbrae

Fimbrae

Finger like connections that connect to the ovary

Ampulla

First part of Fallopian tube

Infundibulum

Middle part of Fallopian Tube

Isthmus

Last part of Fallopian tube that connects to fimbriae

Endometrium

Thick red layer lining the uterus

Placenta

Gray part of uterus that surrounds the embryo

Amnion

Inner membrane

Chorion

Outer membrane

Cervix

On the underside of model

Amniotic Sac

In the placentaA

Amniotic Fluid

Around the baby

Umbilical Cord

Connecting to the 

Vagina

On the underside of the 3 month model