On the top, a series of pictures indicating the various processes involved in fertilization and implantation. They are:

1. Ovulation
2. Fertilization
3. Zygote
4. Two cells
5. Four cells
6. Morula (A solid ball of about sixty four cells)
7. Blastocyst
8. Blastocyst attaches to and then implants into uterine wall

At the bottom, fertilization and implantation occurring inside the human reproductive system is indicated. The various process are indicated using numbers such as one, two, three, four, five, six, seven and eight and the sequence is directed by arrow marks. The parts labeled in the picture are:

1. Ovary
2. Fallopian tube
3. Uterine wall
4. Uterus