| A | B |
|---|
| protective covering of the sperm; contains enzymes | acrosome |
| layers of follicular (ovary) cells that surround the ovum | corona radiata |
| layer of protein & sugar that surrounds the ovum; hardens at fertilization | zona pellucida |
| process arrested in the ovum prior to birth; completed in the ovum after fertilization | meiosis II of ovum |
| entity when binucleate fertilized ovum fuses nuclei | embryo |
| division of cells | cleavage |
| entity consisting of 8 cells | morula or embryo |
| Pregnancy in which embryo remains in the fallopian tube | ectopic |
| first 32 cells of the embryo squeezed into the same volume as the original ovum | compaction |
| hollow embryo entity | blastocyst |
| attachment of embryo in uterine wall | implantation |
| hormone secreted by embryo to prevent menstruation | hCG |
| lining of uterus where embryo burrows in search of nutrients | endometrium |
| layer of disc-shaped embryo that will become the baby's skin, nervous system and hair | ectoderm |
| layer of disc-shaped embryo that will become the baby's digestive system & organs | endoderm |
| layer of disc-shaped embryo that will become the baby's heart, skeleton, kidneys | mesoderm |
| outer layer of chorion that lies in blood-filled cavities of uterus | chorionic frondosium |
| incomplete closure of neural tube at posterior end | spina bifida |
| incomplete closure of neural tube at anterior end | anencephaly |
| completion of embryonic stage | 49 days |
| nuclei of egg & sperm unite in fertilized egg | 12 hours |
| first missed menstrual period | 15 days |
| genitalia begins to differentiate | 50 days |
| first cleavage | 30-36 hours |
| implantation | 8-10 days |
| face plates come together | 34-36 |
| heart begins beating | 21 days |
| fertilized egg | zygote |
| twins that result from 2 separate fertilized eggs | fraternal |
| twins that result from 1 zygote that splits | identical |
| repeated mitotic divisions | cleavage |
| organ comprised of chorionic frondosium & endometrium | placenta |
| fetal urine | amnionic fluid |
| carry oxygen-rich blood from placenta to baby | umbilical vein |
| carries oxygen-deprived blood from baby to placenta | ubilical arteries |
| blood vessel that bypasses the lungs in fetal development by connecting the pulmonary artery to the aorta | ductus arteriosis |
| hole between the right and left atria of fetal heart | foramen oval |
| softening of the cervix | effacing |
| the process of opening the cervix | dilation |
| first stage of labor | dilation/effacing |
| second stage of labor | partuition |
| last stage of labor | placental |
