This section, “The Reproductive System,” presents
a discussion of the organs and structures of the
male and female reproductive systems, an
overview of reproductive and sexual health and
disorders, and entries about the health conditions
that involve the male and female reproductive
systems. “The Urinary System” contains entries
about male organs and structures that share uri-
nary and reproductive functions. “Genetics and
Molecular Medicine” contains entries about the
genetics of reproduction. “The Endocrine System”
contains entries about the sex hormones.
Structures of the Female Reproductive System
BREAST fimbriae
nipple UTERUS
areola CERVIX
lactiferous glands VAGINA
lactiferous ducts Bartholin’s glands
OVARIES hymen
ovum labia
FALLOPIAN TUBES CLITORIS
Structures of the Male Reproductive System
PENIS TESTICLES
foreskin SPERM
glans epididymis
meatus VAS DEFERENS
URETHRA PROSTATE GLAND
corpora cavernosa seminal vesicle
corpus spongiosum urethra
SCROTUM
Functions of the Reproductive System
Human reproduction requires participation from
both male and female, each of which contributes
one half the genetic material necessary for human
existence. The cells that carry this material are the
gametes—the OVA, or eggs, from the female half
and the spermatozoa, or SPERM, from the male
half. Determining gender are the sex chromo-
somes, one from each gamete to form the pair
that designates the gender of the new life. Though
gender distinction is apparent at birth, functional
characteristics of gender do not emerge until late
childhood when hormonal shifts initiate the
changes of PUBERTY. At puberty the levels of
androgens and estrogens increase in the body, ini-
tiating the emergence of the secondary sexual
characteristics that mark reproductive maturity.
From a common beginning: embryonic gender
differentiation The glands that both represent and
sustain gender are the gonads—the OVARIESin the
woman and TESTICLES, or testes, in the man. In the
embryo these structures arise from the same base
cells in the mesoderm (the middle layer of germ
cells in the embryo) called the gonadal ridge. Until
seven weeks, the embryo is androgynous (has no
gender characteristics; male and female appear the
same) with rudimentary structures—the genital
tubercle, labioscrotal swellings, and urogenital
groove and folds—that will evolve into gender-
appropriate organs as the embryo develops.
At seven weeks the gonadal ridge organizes
into a two-layer structure. If the genetic composi-THE REPRODUCTIVE SYSTEM
The organs and functions of the reproductive system make possible the creation of new life. Physician specialists who
treat health conditions of the male reproductive system are urologists. Physician specialists who treat health conditions
of the female reproductive system are gynecologists. Health-care providers who provide care during PREGNANCYand
CHILDBIRTHare obstetricians (physician specialists) and midwives (usually registered nurses). Nurse practitioners (reg-
istered nurses with advanced specialized training and credentials) often function as women’s health-care specialists,
providing routine wellness care and treatment for minor reproductive and SEXUAL HEALTHconditions.
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