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Module 15 in the Syllabus

The Reproductive System Images
Image gallery for study with links to larger teaching JPEGs for classroom presentation

Question Drill for The Reproductive System
Conceptual Vocabulary Self-Test

Basic Terms Crossword Puzzle

Basic Puzzle Solution

Conceptual Vocabulary
SpermatozoonA spermatozoon is the haploid cell that is the male gamete. It joins an ovum to form a zygote.
OvaryAn ovary is the egg-producing reproductive organ found in female organisms
UterusThe uterus or womb is the major female reproductive organ. One end, the cervix, opens into the vagina; the other is connected on both sides to the fallopian tubes.
OvumAn ovum is a haploid female reproductive cell or gamete.
SpermatogenesisSpermatogenesis is the process by which male spermatogonia develop into mature spermatozoa.
AcrosomeThe acrosome is an organelle that develops over the anterior half of the spermatozoon's head which contains digestive enzymes including hyaluronidase and acrosin.
GonadA gonad is an organ that makes gametes.
TestosteroneTestosterone is the principal male sex hormone and an anabolic steroid. It is rimarily secreted in the testes of males and the ovaries of females, although small amounts are also secreted by the adrenal glands.
Ovarian follicleOvarian follicles are the basic unit of female reproductive biology, roughly spherical aggregations of cells found in the ovary.
OocyteAn oocyte is a female gametocyte or germ cell involved in reproduction, in other words, an immature ovum.
Luteinizing hormoneLuteinizing hormone is synthesized and secreted by the anterior lobe of the pituitary gland. In the female, an acute rise of LH triggers ovulation. In the male, LH stimulates Leydig cell production of testosterone.
Follicle-stimulating hormoneFollicle stimulating hormone is secreted by the anterior pituitary gland to stimulate the growth of Graafian follicles in women and enhance the production of androgen-binding protein by Sertoli cells in men.
EstradiolLabelled the female hormone but also present in males, estradiol is the major estrogen in humans, not only of critical importance for reproductive and sexual functioning, but also affects other organs.
ProgesteroneProgesterone is a steroid hormone involved in the female menstrual cycle, pregnancy and embryogenesis.
Menstrual cycleThe menstrual cycle is a recurring cycle of physiologic changes under endocrine control necessary for reproduction that occurs in females.
OvulationOvulation is the process by which a mature ovarian follicle ruptures and discharges an ovum.
MenstruationMenstruation is a phase of the menstrual cycle in which the endometrium is shed.
FertilisationFertilization is fusion of gametes to form a new organism of the same species.
AndrogenAndrogen is the generic term for any natural or synthetic compound, usually a steroid hormone, that stimulates or controls the development and maintenance of masculine characteristics in vertebrates.
OogenesisOogenesis is the creation of an ovum, the female process of gametogenesis.
Corpus luteumThe corpus luteum is a temporary endocrine structure in mammals, involved in the production of the progestogens which are needed for the maintenance of a pregnancy.
Follicular phaseThe follicular phase, or proliferative phase, is the phase of the menstrual cycle during which follicles in the ovary mature to climax with ovulation.
ImplantationImplantation is an event that occurs early in pregnancy in which the embryo adheres to the wall of uterus.
Luteal phaseThe luteal phase, or secretory phase, is the latter phase of the menstrual cycle, which begins with the formation of the corpus luteum and ends in either pregnancy or luteolysis.
PlacentaThe placenta is an ephemeral organ present during pregnancy, which develops from the same sperm and egg cells that form the fetus, and functions as a fetomaternal organ for filtration and transfer.
SpermatogoniumA spermatogonium is an intermediary male gametogonium in the production of spermatozoa.
SpermatocyteA spermatocyte is a male gametocyte which is derived from a spermatogonium.
SpermatidThe term spermatid refers to the haploid male gametid that results from division of secondary spermatocytes.
Seminiferous tubulesSeminiferous tubules are located in the testicles, and are the specific location of meiosis, and the subsequent creation of gametes, namely spermatozoa.
OogoniumAn oogonium is an immature ovum. It is a female gametogonium.
FolliculogenesisFolliculogenesis is the maturation of the ovarian follicle, a densely-packed shell of somatic cells that contains an immature oocyte.
MenopauseThe word menopause literally means the permanent physiological, or natural, cessation of menstrual cycles.
EndometriumThe endometrium is the inner membrane of the uterus.
LactationLactation describes the secretion of milk from the mammary glands, the process of providing that milk to the young, and the period of time that a mother lactates to feed her young.
GametidA gametid is a kind of germ cell that results from the meiosis of a gametocyte.
Leydig cellFound adjacent to the seminiferous tubules in the testicle, Leydig cells can secrete testosterone and are often closely related to nerves.
Granulosa cellsA granulosa cell is a somatic cell found closely associated with the developing oocyte within the ovary.
Human chorionic gonadotropinHuman chorionic gonadotropin is a peptide hormone made by the embryo soon after conception and later by the placenta, preventing the disintegration of the corpus luteum and thereby maintaining progesterone levels for pregnancy.
MenarcheMenarche refers to the first menstrual period, or first menstrual bleeding.
Zona pellucidaThe zona pellucida is a glycoprotein membrane surrounding the plasma membrane of an oocyte.
ChorionThe chorion, which surrounds the embryo and other membranes, consists of two layers: an outer layer formed by the primitive ectoderm or trophoblast, and an inner layer formed by the somatic mesoderm in contact with the amnion.
AmnionThe amnion is a membranous sac which surrounds and protects the embryo.
HyaluronidaseA hyaluronidases is an enzyme released by the acrosome of the sperm cell that degrade hyaluronic acid.
Acrosome reactionThe acrosome reaction is the reaction which occurs in the anterior of the sperm's head as it approaches the zona pellucida.
CapacitationCapacitation is the final step in the maturation of mammalian spermatozoa and is required to render them competent to fertilize an oocyte.
Cortical reactionThe cortical reaction, also known as the zona reaction, occurs when a sperm unites with the egg's plasma membrane, altering the zona pellucida to prevent other sperm from binding to and entering the egg.
Sertoli cellActivated by follicle-stimulating hormone, sertoli cells are 'nurse' cell of the testes, nurturing developing sperm cells within the seminiferous tubules.
InhibinInhibin is a peptide that is an inhibitor of FSH synthesis and secretion, participating in the regulation of the menstrual cycle.
ActivinActivin is a peptide that enhances FSH synthesis and secretion and participates in the regulation of the menstrual cycle.
EpididymisThe epididymis is a narrow, tightly-coiled tube connecting the efferent ducts of each testicle to its vas deferens.
Vas deferensThe vas deferens are muscular tubes surrounded by smooth muscle connecting the left and right epididymis to the ejaculatory ducts.
Bulbourethral glandA bulbourethral gland, or Cowper's gland, is one of two small exocrine glands present in the reproductive system of human males. During sexual arousal each gland produces a clear, viscous secretion known as pre-ejaculate.
ProstateThe prostate is a compound tubuloalveolar exocrine gland of the male mammalian reproductive system.
ViviparousIn a viviparous animal, the embryo develops inside the body of the mother, as opposed to outside within an egg.
EstroneEstrone is an estrogenic hormone secreted by the ovary, the least prevalent of the three estrogens, which also include estriol and estradiol.
ColostrumColostrum is a form of milk produced by the mammary glands in late pregnancy and the few days after giving birth.
Chorionic villiChorionic villi are tiny, finger-like structures that sprout from the chorion, in order to give a maximum area of contact with the maternal blood.
Yolk sacThe yolk sac is the first element seen in the gestational sac during pregnancy, usually at 5 weeks gestation. It is filled with the vitelline fluid.
Advanced terms that may appear in context in MCAT passages
AcrosinAcrosin is a protease released from the acrosome of spermatozoa as a consequence of the acrosome reaction
SpermatocytogenesisSpermatocytogenesis is the male form of gametocytogenesis which involves stem cells dividing to produce a population of cells destined to become mature sperm.
SpermatidogenesisSpermatidogenesis is the creation of spermatids from secondary spermatocytes during spermatogenesis.
SpermiogenesisSpermiogenesis is the final stage of spermatogenesis which sees the maturation of spermatids into mature, motile spermatozoa.
Human placental lactogenHuman placental lactogen, also called human chorionic somatomammotropin, is a polypeptide placental hormone that modifies the metabolic state of the mother during pregnancy to facilitate the energy supply of the fetus.
TrophoblastTrophoblasts are cells forming the outer layer of a blastocyst. They provide nutrients to the embryo and develop into a large part of the placenta.
Androgen binding proteinAndrogen-binding protein is a glycoprotein produced by the Sertoli cells in the testis which binds specifically to testosterone, dihydrotestosterone, and 17-beta-estradiol.
Efferent ductsThe efferent ducts are part of the testis, connecting the rete testis with the head of the epididymis.
DehydroepiandrosteroneDehydroepiandrosterone is a steroid prohormone produced from cholesterol. It is the precursor of androstenedione, which undergoes further conversion to produce testosterone, estrone or estradiol.
AndrostenedioneAndrostenedione is a steroid intermediate fromed from dehydroepiandrosterone in the biochemical pathway that produces the androgen testosterone and the estrogens estrone and estradiol.
AndrosteroneAndrosterone is a steroid hormone with weak androgenic activity, made in the liver from the metabolism of testosterone.
DihydrotestosteroneDihydrotestosterone is a biologically active metabolite of the hormone testosterone, formed primarily in the prostate gland, testes, hair follicles, and adrenal glands by the enzyme 5 alpha-reductase.
Cumulus oophorusThe cumulus oophorus is a mass of cells of the membrana granulos projecting into the cavity of a mature Graafian follicle.
GonadotropeGonadotropes are cells in the anterior pituitary which produce the gonadotropins follicle-stimulating hormone and luteinizing hormone.
AromataseAromatase is an enzyme of the cytochrome P450 superfamily whose function is to aromatize androgens, that is, to selectively increase their aromaticity, producing estrogens.
SyncytiotrophoblastSyncytiotrophoblasts are multinucleated cells found in the placenta of human embryos that form the outermost fetal component of the placenta and massively increase the surface area available for nutrient exchange.
Vitelline veinsThe vitelline veins are veins which drain blood from the yolk sac.
Vitelline circulationVitelline circulation refers to the system of blood flowing from the embryo to the yolk sac and back again.
Vitelline ductVitelline duct

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