Across
- 5. the fusion of sperm and egg nuclei
- 6. layers of cells that provide protection and nourishment to developing egg cell
- 8. protective coat on oocyte
- 12. when sperm cells swim through the corona radiata and attach to receptors on the zona pellucida
- 14. a flexible cordlike structure containing blood vessels and attaching a human or other mammalian fetus to the placenta during gestation
- 15. projections that later form placenta with maternal tissues
- 16. delivers oxygen, nutrients, removes waste, and secretes estrogen and progesterone for maintaining
- 18. developing baby after 9 weeks
- 19. weeks and stages that divide pregnancy (milestones)
- 20. childbirth
- 21. human chorionic gonadotropin, hormone detected in pregnancy test
Down
- 1. the innermost membrane that encloses the embryo
- 2. developing baby
- 3. actual age of the baby
- 4. age of pregnancy, starting from first day of last period
- 7. when blastocyst attaches to endometrium and embedded in the mucosa
- 9. period of time from conception to birth of baby
- 10. tissue layers are formed after blastocyst stage
- 11. stage between zygote and embryo
- 13. single diploid cell, the first cell of baby
- 17. a series of rapid mitotic divisions changing zygote to blastocyst