abortion-The termination of a pregnancy in
progress.
asexual
reproduction-A type of reproduction involving only
one parent that produces genetically identical offspring by budding or by the
division of a single cell or the entire organism into two or more parts.
assisted
reproductive technology-Fertilization procedures that generally
involve the surgical removal of eggs (secondary oocytes) from a woman’s ovaries
following hormonal stimulation, fertilizing the eggs, and returning them to the
woman’s body.
baculum-A bone that is contained in, and helps
stiffen, the penis of rodents, raccoons, walruses, whales, and several other
mammals.
barrier
methods-Contraception that relies on a physical barrier to block the
passage of sperm. Examples include condoms and diaphragms.
bartholins
gland-Glands near the vaginal opening in a human female that secrete
lubricating fluid during sexual arousal.
birth
control pill-Chemical contraceptives that inhibit
ovulation, retard follicular development, or alter a woman’s cervical mucus to
prevent sperm from entering the uterus.
blastocyst-An embryonic stage in mammals; a hollow
ball of cells produced one week after fertilization in humans.
budding-An asexual means of propagation in
which outgrowths from the parent form and pinch off to live independently or
else remain attached to eventually form extensive colonies.
bulbourethral
glands-One of a pair of glands near the base of the penis in the human
male that secretes fluid that lubricates and neutralizes acids in the urethra
during sexual arousal.
cervix-The neck of the uterus, which opens
into the vagina.
cleavage-The process of cytokinesis in animal
cells, characterized by pinching of the plasma membrane; specifically, the
succession of rapid cell divisions without growth during early embryonic
development that converts the zygote into a ball of cells.
clitoris
-An organ in the female that engorges with blood and becomes erect
during sexual arousal.
cloaca-A common opening for the digestive,
urinary, and reproductive tracts found in many nonmammalian vertebrates but in
few mammals.
coitus-The insertion of a penis into a vagina,
also called sexual intercourse.
conception-The fertilization of the egg by a sperm
cell in humans.
condom-A thin, latex rubber or natural
membrane sheath that fits over the penis to collect semen.
contraception-The prevention of pregnancy.
corpus
luteum-A secreting tissue in the ovary that forms from the collapsed
follicle after ovulation and produces progesterone.
diaphragm-(1) A sheet of muscle that forms the
bottom wall of the thoracic cavity in mammals; active in ventilating the lungs.
(2) A dome-shaped rubber cup fitted into the upper portion of the vagina before
sexual intercourse. It serves as a physical barrier to block the passage of
sperm.
ejaculation-The propulsion of sperm from the
epididymis through the muscular vas deferens, ejaculatory duct, and urethra.
ejaculatory
duct-The short section of the ejaculatory route in mammals formed by
the convergence of the vas deferens and a duct from the seminal vesicle. The
ejaculatory duct transports sperm from the vas deferens to the urethra.
endometrium-The inner lining of the uterus, which
is richly supplied with blood vessels.
epididymus-A coiled tubule located adjacent to the
testes where sperm are stored.
estrous
cycles -A type of reproductive cycle in all female mammals except higher
primates, in which the nonpregnant endometrium is reabsorbed rather than shed,
and sexual response occurs only during mid-cycle at estrus.
estrus-A period of sexual activity associated
with ovulation.
external
fertilization-The fusion of gametes that parents have
discharged into the environment.
fetilization-The union of haploid gametes to produce
a diploid zygote.
fetus-A developing human from the ninth week
of gestation until birth; has all the major structures of an adult.
follicle-A microscopic structure in the ovary
that contains the developing ovum and secretes estrogens.
follicular
cycle-
fragmentation-A means of asexual reproduction whereby
a single parent breaks into parts that regenerate into whole new individuals.
gametes-A haploid cell, such as an egg or
sperm. Gametes unite during sexual reproduction to produce a diploid zygote.
gametogenesis-The process by which gametes are produced
in the mammalian body.
gestation-Pregnancy; the state of carrying
developing young within the female reproductive tract.
glans
penis-The head end of the penis.
gonads-The male and female sex organs; the
gamete-producing organs in most animals.
hermaphroditism
-A condition in which an individual has both female and male gonads
and functions as both a male and female in sexual reproduction by producing
both sperm and eggs.
human
chorionic gonadotropin-A hormone secreted by the chorion that
maintains the corpus luteum of the ovary during the first three months of
pregnancy.
hymen-A thin membrane that partly covers the
vaginal opening in the human female. The hymen is ruptured by sexual
intercourse or other vigorous activity.
internal
fertilization -Reproduction in which sperm are
typically deposited in or near the female reproductive tract and fertilization
occurs within the tract.
in
vitro fertilization -Fertilization of ova in laboratory
containers followed by artificial implantation of the early embryo in the
mother’s uterus.
labia
majora-A pair of thick, fatty ridges that enclose and protect the labia
minor and vestibule.
labia
minora-A pair of slender skin folds that enclose and protect the
vestibule.
labor-A series of strong, rhythmic
contractions of the uterus that expel a baby out of the uterus and vagina
during childbirth.
leydig
cells-A cell that produces testosterone and other androgens and is
located between the seminiferous tubules of the testes.
luteal
phase-That portion of the ovarian cycle during which endocrine cells of
the corpus luteum secrete female hormones.
menopause-The cessation of ovulation and
menstruation.
menstrual
cycle-A type of reproductive cycle in higher female primates, in which
the nonpregnant endometrium is shed as a bloody discharge through the cervix
into the vagina.
menstruation-The shedding of portions of the
endometrium during a uterine (menstrual) cycle.
menustral
flow phase-The shedding of portions of the endometrium during a uterine
(menstrual) cycle.
mytonia-Increased muscle tension.
natural
family planning-A form of contraception that relies on
refraining from sexual intercourse when conception is most likely to occur;
also called the rhythm method.
oogenesis-The process in the ovary that results
in the production of female gametes.
organogenesis-The development of organ rudiments from
the three germ layers.
orgasm-Rhythmic, involuntary contractions of
certain reproductive structures in both sexes during the human sexual response
cycle.
ovarian
cycle-The cyclic recurrence of the follicular phase, ovulation, and the
luteal phase in the mammalian ovary, regulated by hormones.
ovaries-(1) In flowers, the portion of a carpel
in which the egg-containing ovules develop. (2) In animals, the structure that
produces female gametes and reproductive hormones.
oviduct-A tube passing from the ovary to the vagina in invertebrates or to
the uterus in vertebrates.
ovulation-The release of an egg from ovaries. In humans, an ovarian follicle
releases an egg during each uterine (menstrual) cycle.
parthogenesis-A type of reproduction in which females produce offspring from
unfertilized eggs.
parturition-The expulsion of a baby from the mother; also called birth.
penis-The copulatory structure of male mammals.
pheromones-In animals and fungi, a small, volatile chemical that functions in
communication and that in animals acts much like a hormone in influencing
physiology and behavior.
placenta-A structure in the pregnant uterus for nourishing a viviparous
fetus with the mother’s blood supply; formed from the uterine lining and
embryonic membranes.
pregancy-The condition of carrying one or more embryos in the uterus.
prepuce-A fold of skin covering the head of the clitoris and penis.
proliferative
phase-That portion of the uterine
(menstrual) cycle when the endometrium regenerates and thiA gland in human
males that secretes an acid-neutralizing component of semen. ckens.
prostate
gland-A gland in human males that
secretes an acid-neutralizing component of semen.
regeneration-The regrowth of body parts from pieces of an organism.
rhythm
method-A form of contraception that
relies on refraining from sexual intercourse when conception is most likely to
occur; also called natural family planning.
scrotum-A pouch of skin outside the abdomen that houses a testis;
functions in cooling sperm, thereby keeping them viable.
secretory
phase-That portion of the uterine
(menstrual) cycle when the endometrium continues to thicken, becomes more
vascularized, and develops glands that secrete a fluid rich in glycogen.
semen-The fluid that is ejaculated by the male during orgasm; contains
sperm and secretions from several glands of the male reproductive tract.
seminal
vesicles-A gland in males that
secretes a fluid component of semen that lubricates and nourishes sperm.
seminiferous
tubules- A gland in males that
secretes a fluid component of semen that lubricates and nourishes sperm. A
highly coiled tube in the testis in which sperm are produced.
sequential
hermaphroditism-A
reproductive pattern in which an individual reverses its sex during its
lifetime.
sexual
reproduction -A type of
reproduction in which two parents give rise to offspring that have unique
combinations of genes inherited from the gametes of the two parents.
spermatheca-A sac in the female reproductive system where sperm are stored.
spermatogenesis-The continuous and prolific production of mature sperm cells in
the testis.
testes-(plural, testes) The male reproductive organ, or
gonad, in which sperm and reproductive hormones are produced.
trimesters-In human development, one of three 3 month-long periods of
pregnancy.
trophoblast-The outer epithelium of the blastocyst, which forms the fetal part
of the placenta.
tubal
ligation-A means of sterilization
in which a woman’s two oviducts (Fallopian tubes) are tied closed to prevent
eggs from reaching the uterus. A segment of each oviduct is removed.
urethra-A tube that releases urine from the body near the vagina in
females and through the penis in males; also serves in males as the exit tube
for the reproductive system.
uterine
cycle-The changes that occur in the
uterus during the reproductive cycle of the human female; also called the
menstrual cycle.
uterus-A female organ where eggs are fertilized and/or development of the
young occurs.
vagina-Part of the female reproductive system between the uterus and the
outside opening; the birth canal in mammals; also accommodates the male’s penis
and receives sperm during copulation.
vas
deferens-The tube in the male
reproductive system in which sperm travel from the epididymis to the urethra.
vasectomy-The cutting of each vas deferens to prevent sperm from entering
the urethra.
vasocongestion-The filling of a tissue with blood, caused by increased blood flow
through the arteries of that tissue.
vestibule-The cavity enclosed by the labia minora; the space into which the
vagina and urethral opening empty.
vulva-Collective term for the female external genetalia.
zygote-The diploid product of the union of haploid gametes in conception;
a fertilized egg.