Chapter 21: Reproductive System

Reproductive system

The body system responsible for producing offspring and maintaining sexual characteristics.

Gonads

Organs that produce gametes; testes in males and ovaries in females.

Gametes

Reproductive cells; sperm in males and ova (eggs) in females.

Testes

Male gonads that produce sperm and testosterone.

Scrotum

A sac that holds and regulates the temperature of the testes.

Sperm

Male reproductive cells that fertilize a female egg.

Epididymis

A coiled tube where sperm mature and are stored.

Vas deferens

A duct that transports sperm from the epididymis to the urethra.

Seminal vesicles

Glands that secrete a fluid rich in sugar to nourish sperm.

Prostate gland

A gland that produces alkaline fluid to help sperm survive the vaginal environment.

Bulbourethral glands

Glands that secrete a lubricating fluid prior to ejaculation.

Semen

A mixture of sperm and fluids from the male reproductive glands.

Penis

The male external organ that delivers semen into the female reproductive tract.

Ovaries

Female gonads that produce ova (eggs) and secrete estrogen and progesterone.

Ova (egg cells)

Female reproductive cells that, when fertilized, develop into a fetus.

Ovulation

The release of a mature egg from the ovary.

Fallopian tubes

Tubes that transport the egg from the ovary to the uterus; site of fertilization.

Fimbriae

Finger-like projections at the end of the fallopian tubes that help capture the egg.

Uterus

A muscular organ where a fertilized egg implants and develops during pregnancy.

Endometrium

The inner lining of the uterus that thickens in preparation for implantation.

Cervix

The lower, narrow portion of the uterus that opens into the vagina.

Vagina

A muscular canal that receives the penis during intercourse and serves as the birth canal.

Labia

The folds of skin surrounding the vaginal opening.

Clitoris

A sensitive female organ that is part of the external genitalia.

Menstrual cycle

A monthly cycle of changes in the uterus and ovaries that includes ovulation and menstruation.

Menstruation

The shedding of the uterine lining when fertilization does not occur.

Estrogen

A hormone that regulates female sexual development and reproductive functions.

Progesterone

A hormone that prepares the uterus for pregnancy and maintains it if pregnancy occurs.

Testosterone

The primary male sex hormone responsible for male characteristics and sperm production.

Fertilization

The union of a sperm and an egg to form a zygote.

Zygote

A fertilized egg cell that begins development into an embryo.

Pregnancy

The period of development from fertilization to birth.

Embryo

The early stage of human development from implantation to the eighth week.

Fetus

The developing human from the ninth week of pregnancy to birth.

Placenta

An organ that forms during pregnancy to nourish and remove waste from the fetus.

Amniotic sac

A fluid-filled membrane that surrounds and protects the developing fetus.

Labor

The process of childbirth, including uterine contractions and delivery.

Menopause

The natural cessation of menstruation, typically occurring in middle age.

Erectile dysfunction (ED)

The inability to achieve or maintain an erection.

Prostate cancer

A common cancer in older men affecting the prostate gland.

Endometriosis

A condition in which endometrial tissue grows outside the uterus.

Ovarian cyst

A fluid-filled sac on or in an ovary.

Infertility

The inability to conceive after one year of unprotected intercourse.

Contraception

Methods used to prevent pregnancy.