Fertilization/conception

First cell division occurs ___ hours after chromosome fusion

12

How long will egg wait to be fertilized?

12-24 hours

Conception-

2 cells (egg + sperm) join together to make one cell

Conception is possible every

28 days

Cell division repeats

3 days, every 12-15 hours

Sperm survive up to

5 days

The fertilized egg is called a blastocyst after

5 days, inside the uterus

The journey from vagina to Fallopian tube is

6-7 inches, takes several hours

Blastocyst has

60-70 cells, 4th day

implantation occurs

8 days after fertilization

Blastocyst

Attaches to uterine wall (implantation)

unfertilized egg

Begins to disintegrate + die

Sperm head travels to nucleus of ovum and the

Chromosomes combine

Where is the ova fertilized?

Fallopian tube

Zygote/germinal stage is the

First two weeks post conception

Sperm genetic material is in the

Head

____ out of ____ sperm reach the egg

Hundreds out of millions

Result of egg's death

Large quantities of progesterone sent into blood, cueing uterine lining to be shed

Once sperm as penetrated the egg, it's tail

Separates from the head, dies

identical twins

Single egg, divided + fertilized

Sperm genetic material

Spreads out to form nucleus. M+F nuclei join together

When a sperm breaks through egg wall

The chemical structure of the egg changes to shut out remaining sperm

Zygote

The fertilized egg

Pregnancy in the Fallopian tube

Tubal pregnancy

fraternal twins

Two fertilized eggs

First cell is called the

Zygote

embryo

the developing human organism from about 2 /3 weeks after fertilization through the second month