Key Terms Chapter 27: The Reproductive System

alveoli

(of the breast) milk-secreting cells in the mammary gland

ampulla

(of the uterine tube) middle portion of the uterine tube in which fertilization often occurs

antrum

fluid-filled chamber that characterizes a mature tertiary (antral) follicle

areola

highly pigmented, circular area surrounding the raised nipple and containing areolar glands that secrete fluid important for lubrication during suckling

Bartholin’s glands

(also, greater vestibular glands) glands that produce a thick mucus that maintains moisture in the vulva area; also referred to as the greater vestibular glands

blood–testis barrier

tight junctions between Sertoli cells that prevent bloodborne pathogens from gaining access to later stages of spermatogenesis and prevent the potential for an autoimmune reaction to haploid sperm

body of uterus

middle section of the uterus

broad ligament

wide ligament that supports the uterus by attaching laterally to both sides of the uterus and pelvic wall

bulbourethral glands

(also, Cowper’s glands) glands that secrete a lubricating mucus that cleans and lubricates the urethra prior to and during ejaculation

cervix

elongate inferior end of the uterus where it connects to the vagina

clitoris

(also, glans clitoris) nerve-rich area of the vulva that contributes to sexual sensation during intercourse

corpus albicans

nonfunctional structure remaining in the ovarian stroma following structural and functional regression of the corpus luteum

corpus cavernosum

either of two columns of erectile tissue in the penis that fill with blood during an erection

corpus luteum

transformed follicle after ovulation that secretes progesterone

corpus spongiosum

(plural = corpora cavernosa) column of erectile tissue in the penis that fills with blood during an erection and surrounds the penile urethra on the ventral portion of the penis

ductus deferens

(also, vas deferens) duct that transports sperm from the epididymis through the spermatic cord and into the ejaculatory duct; also referred as the vas deferens

ejaculatory duct

duct that connects the ampulla of the ductus deferens with the duct of the seminal vesicle at the prostatic urethra

endometrium

inner lining of the uterus, part of which builds up during the secretory phase of the menstrual cycle and then sheds with menses

epididymis

(plural = epididymides) coiled tubular structure in which sperm start to mature and are stored until ejaculation

fimbriae

fingerlike projections on the distal uterine tubes

follicle

ovarian structure of one oocyte and surrounding granulosa (and later theca) cells

folliculogenesis

development of ovarian follicles from primordial to tertiary under the stimulation of gonadotropins

fundus

(of the uterus) domed portion of the uterus that is superior to the uterine tubes

gamete

haploid reproductive cell that contributes genetic material to form an offspring

glans penis

bulbous end of the penis that contains a large number of nerve endings

gonadotropin-releasing hormone (GnRH)

hormone released by the hypothalamus that regulates the production of follicle-stimulating hormone and luteinizing hormone from the pituitary gland

gonads

reproductive organs (testes in men and ovaries in women) that produce gametes and reproductive hormones

granulosa cells

supportive cells in the ovarian follicle that produce estrogen

hymen

membrane that covers part of the opening of the vagina

infundibulum

(of the uterine tube) wide, distal portion of the uterine tube terminating in fimbriae

inguinal canal

opening in abdominal wall that connects the testes to the abdominal cavity

isthmus

narrow, medial portion of the uterine tube that joins the uterus

labia majora

hair-covered folds of skin located behind the mons pubis

labia minora

thin, pigmented, hairless flaps of skin located medial and deep to the labia majora

lactiferous ducts

ducts that connect the mammary glands to the nipple and allow for the transport of milk

lactiferous sinus

area of milk collection between alveoli and lactiferous duct

Leydig cells

cells between the seminiferous tubules of the testes that produce testosterone; a type of interstitial cell

mammary glands

glands inside the breast that secrete milk

menarche

first menstruation in a pubertal female

menses

shedding of the inner portion of the endometrium out though the vagina; also referred to as menstruation

menses phase

phase of the menstrual cycle in which the endometrial lining is shed

menstrual cycle

approximately 28-day cycle of changes in the uterus consisting of a menses phase, a proliferative phase, and a secretory phase

mons pubis

mound of fatty tissue located at the front of the vulva

Müllerian duct

duct system present in the embryo that will eventually form the internal female reproductive structures

myometrium

smooth muscle layer of uterus that allows for uterine contractions during labor and expulsion of menstrual blood

oocyte

cell that results from the division of the oogonium and undergoes meiosis I at the LH surge and meiosis II at fertilization to become a haploid ovum

oogenesis

process by which oogonia divide by mitosis to primary oocytes, which undergo meiosis to produce the secondary oocyte and, upon fertilization, the ovum

oogonia

ovarian stem cells that undergo mitosis during female fetal development to form primary oocytes

ovarian cycle

approximately 28-day cycle of changes in the ovary consisting of a follicular phase and a luteal phase

ovaries

female gonads that produce oocytes and sex steroid hormones (notably estrogen and progesterone)

ovulation

release of a secondary oocyte and associated granulosa cells from an ovary

ovum

haploid female gamete resulting from completion of meiosis II at fertilization

penis

male organ of copulation

perimetrium

outer epithelial layer of uterine wall

polar body

smaller cell produced during the process of meiosis in oogenesis

prepuce

(also, foreskin) flap of skin that forms a collar around, and thus protects and lubricates, the glans penis; also referred as the foreskin

primary follicles

ovarian follicles with a primary oocyte and one layer of cuboidal granulosa cells

primordial follicles

least developed ovarian follicles that consist of a single oocyte and a single layer of flat (squamous) granulosa cells

proliferative phase

phase of the menstrual cycle in which the endometrium proliferates

prostate gland

doughnut-shaped gland at the base of the bladder surrounding the urethra and contributing fluid to semen during ejaculation

puberty

life stage during which a male or female adolescent becomes anatomically and physiologically capable of reproduction

rugae

(of the vagina) folds of skin in the vagina that allow it to stretch during intercourse and childbirth

scrotum

external pouch of skin and muscle that houses the testes

secondary follicles

ovarian follicles with a primary oocyte and multiple layers of granulosa cells

secondary sex characteristics

physical characteristics that are influenced by sex steroid hormones and have supporting roles in reproductive function

secretory phase

phase of the menstrual cycle in which the endometrium secretes a nutrient-rich fluid in preparation for implantation of an embryo

semen

ejaculatory fluid composed of sperm and secretions from the seminal vesicles, prostate, and bulbourethral glands

seminal vesicle

gland that produces seminal fluid, which contributes to semen

seminiferous tubules

tube structures within the testes where spermatogenesis occurs

Sertoli cells

cells that support germ cells through the process of spermatogenesis; a type of sustentacular cell

sperm

(also, spermatozoon) male gamete

spermatic cord

bundle of nerves and blood vessels that supplies the testes; contains ductus deferens

spermatid

immature sperm cells produced by meiosis II of secondary spermatocytes

spermatocyte

cell that results from the division of spermatogonium and undergoes meiosis I and meiosis II to form spermatids

spermatogenesis

formation of new sperm, occurs in the seminiferous tubules of the testes

spermatogonia

(singular = spermatogonium) diploid precursor cells that become sperm

spermiogenesis

transformation of spermatids to spermatozoa during spermatogenesis

suspensory ligaments

bands of connective tissue that suspend the breast onto the chest wall by attachment to the overlying dermis

tertiary follicles

(also, antral follicles) ovarian follicles with a primary or secondary oocyte, multiple layers of granulosa cells, and a fully formed antrum

testes

(singular = testis) male gonads

theca cells

estrogen-producing cells in a maturing ovarian follicle

uterine tubes

(also, fallopian tubes or oviducts) ducts that facilitate transport of an ovulated oocyte to the uterus

uterus

muscular hollow organ in which a fertilized egg develops into a fetus

vagina

tunnel-like organ that provides access to the uterus for the insertion of semen and from the uterus for the birth of a baby

vulva

external female genitalia

Wolffian duct

duct system present in the embryo that will eventually form the internal male reproductive structures