Module 3

1. Module 3

1.10. Page 4

Lesson 2

Module 3—The Male and Female Reproductive Systems

Lesson Summary

In Lesson 2 you investigated the following focusing questions:

What are the essential structures and functions of the female reproductive system?
How do these structures support continuity of the human species?
What is the functional unit of the female reproductive system?

The female reproductive system is designed to produce a very limited number of gametes. The female gonads (ovaries) produce the egg (ovum), the functional unit of reproduction for the female. An egg is further matured inside a follicle, within an ovary. Once matured, the egg, through the process of ovulation, ruptures out of the ovary. Outside of the ovary, the fimbriae pick up the egg and sweep it into the oviduct (Fallopian tube). With the help of cilia and muscle contractions in the oviduct, the egg is transported to the uterus. If a sperm fertilizes the egg in the oviduct, the resulting zygote may implant in the uterus, resulting in the development of a new human life. If a sperm does not fertilize the ovum, the ovum is transported out of the uterus during menstruation with the shedding of the endometrial lining through the cervix and vagina to the outside of the body.

Because only a limited number of gametes are produced, protection of the egg and the developing embryo is critical. Their protection is ensured by internal fertilization and development. The female reproductive system is one-half of the equation that brings a new human life into the world and contributes to the continuation of the human species.

Lesson Glossary

Consult the glossary in the textbook for other definitions that you may need to complete your work.

cervix: the tightly constricted opening from the vagina into the uterus

dysmenorrhea: severe menstrual cramps

egg [ovum (singular), ova (plural), oocyte]: the female gamete that contributes half of the chromosomes to the zygote in sexual reproduction

embryo: the offspring in the period of development from the cleavage of the zygote to the ninth week, when the embryo becomes a fetus

endometrial lining: the lining of the uterus that is thickened monthly to allow implantation of an embryo, and is shed in menstruation if fertilization does not occur

fimbriae: finger-like projections that sweep the ovulated ovum into the oviduct

follicles: specialized cells that surround and nurture the developing ova in the ovary and that secrete estrogen and progesterone

menarche: a female’s first menstrual cycle

menstruation: the monthly shedding of the endometrial lining

ovaries: the paired female gonads that produce eggs and secrete progesterone and estrogen hormones

oviduct (Fallopian tube): the cilia-lined tube of smooth muscle that carries the ovulated egg from each ovary to the uterus

ovulation: the release of the mature ovum from the follicle of the ovary into the oviduct

uterus: the reproductive organ in which embryonic and fetal development occurs

vagina: the muscular tube that leads from the uterus to the external environment

vulva: the external female genital organs

zygote (fertilized egg): a single cell produced by the fusion of the egg and sperm