| A | B |
|---|
| Testes | The gamete-producing organs of the male reproductive system. |
| Seminiferous tubules | Tighly coiled tubules within the testes where male gametes are produced. |
| Scrotum | An external sac that holds the testes. |
| Epididymis | A long, coiled tubule that is closely attached to each testis. This is where the sperm matures and gains the ability to swim. |
| Sperm | The male gamete. |
| Vas deferens | A duct that extends from the epididymis. Smooth muscles that line the vas deferens contract to help move sperm along as they exit the body. |
| Semen | A fluid formed from sperm and various exocrine secretions. |
| Penis | The organ that deposits sperm in the female reproductive system. |
| Ejaculation | When semen is forcefully expelled from the penis from contractions of the smooth muscles that line the urethra. |
| Eggs (Ova) | The female gamete. |
| Ovaries | The gamete-producing organs of the female reproductive system. |
| Ovum | A mature egg. |
| Fallopian tube (Uterine tube) | The narrow passageway that leads to the uterus. |
| Uterus | A hollow, muscular organ about the size of a fist. Where the fertilized egg will develop. |
| Cervix | The lower entrance to the uterus. |
| Vagina | A muscular tube that leads to the outside of the female's body. It receives sperm from the penis and is the channel through which a baby passes during childbirth. |
| Vulva | The external structures of the female reproductive system. |
| Labia | Part of the vulva; contains folds of skin and mucous membranes that cover and protect the opening to the female reproductive system. |
| Menstral cycle | A series of changes that prepare the female reproductive system for a possible pregnancy. |
| Follicular phase | When an immature egg completes the first meiotic division. |
| Follicle | A layer of cells that surround an immature egg. |
| Ovulation | The release of an egg from a ruptured follicle. |
| Corpus luteum | When the cells of the ruptured follicle grow larger and fill the cavity. |
| Luteal phase | When the corpus luteum forms and produces large amounts of progestrone and estrogen which thickens the uterine lining. |
| Menstration | The lining of the uterus and blood from ruptured blood vessels are discharged from the vagina. |
| Menopause | When menstration ceases. |
| Gestation | A series of changes that transforms a single cell into a complex organism made of trillions of cells. |
| Morula | A hollow ball of cells resulting from cleavage of the zygote. |
| Blastocyst | A ball of cells with a large, fluid filled cavity. |
| Implantation | The process in which the blastocyst burrows and embeds itself into the lining of the uterus. |
| Pregnancy | The nine-month period of gestation in humans. |
| Trimesters | Three equal periods of pregnancy in humans. |
| Amniotic sac | One of four membranes that help in the development of the embryo. It is fluid-filled and the fluid cushions the embryo from injury and keeps it moist. |
| Chorionic villi | Many small, fingerlike projections that help attach the embryo to the uterus. |
| Umbilical cord | Contains arteries and veins that carry blood between the fetus and the placenta. |
| Human chorionic gonadotropin (HCG) | A hormone that stimulates the corpus luteum to continue producing sex hormones, thus retaining the uterine lining. |
| Fetus | The developing child from eight weeks until birth. |
| Labor | The muscular contractions and other events that lead up to childbirth. |
| Afterbirth | The expulsion of the placenta, amnion, and the uterine lining about 10 minutes after birth. |
