Which cells, located in the connective tissue between the seminiferous tubules, secrete testosterone?
Leydig cells
✓
Sertoli cells
Spermatogonia
Myoepithelial cells
Correct Answer
Leydig cells
Leydig cells, also called interstitial cells, sit between the seminiferous tubules and release testosterone when stimulated by luteinizing hormone. Sertoli cells line the tubules and support developing sperm rather than making testosterone. Spermatogonia are the stem cells that give rise to sperm. Myoepithelial cells are contractile cells found in glands such as the breast.
Category: Testicular Hormones
Question 2
Sertoli cells secrete which hormone that selectively suppresses FSH release from the anterior pituitary?
Prolactin
Inhibin
✓
Oxytocin
Relaxin
Correct Answer
Inhibin
Inhibin is released by Sertoli cells and provides negative feedback that lowers FSH secretion, so its level reflects spermatogenic activity. Prolactin is an anterior pituitary hormone best known for milk production. Oxytocin is a posterior pituitary hormone that drives uterine contraction and milk ejection. Relaxin is associated with pregnancy and loosening of pelvic ligaments.
Category: Testicular Hormones
Question 3
In which long, coiled duct on the back of each testis do sperm mature and get stored before ejaculation?
Rete testis
Seminal vesicle
Epididymis
✓
Prostate gland
Correct Answer
Epididymis
The epididymis is a tightly coiled tube where sperm gain the ability to swim and are held until ejaculation. The rete testis is a network of channels inside the testis that sperm pass through earlier. A seminal vesicle is an accessory gland that adds fluid to semen. The prostate gland surrounds the urethra and contributes fluid, not storage.
Category: Male Ducts and Glands
Question 4
Which accessory glands contribute roughly 60 percent of semen volume and supply fructose as an energy source for sperm?
Prostate gland
Bulbourethral glands
Testes
Seminal vesicles
✓
Correct Answer
Seminal vesicles
The seminal vesicles produce the largest share of semen, and their fluid is rich in fructose that sperm use to make ATP. The prostate gland adds a smaller volume of fluid that helps semen coagulate and then liquefy. Bulbourethral glands release a small amount of lubricating fluid before ejaculation. The testes produce sperm, which make up only a small fraction of semen volume.
Category: Male Ducts and Glands
Question 5
Which column of erectile tissue in the penis surrounds the urethra and expands at its tip to form the glans?
Corpus spongiosum
✓
Corpus cavernosum
Tunica albuginea
Prepuce
Correct Answer
Corpus spongiosum
The single corpus spongiosum runs along the underside of the penis around the urethra and enlarges distally as the glans. The paired corpus cavernosum columns make up most of the penile bulk but do not surround the urethra. The tunica albuginea is a dense connective tissue covering, not erectile tissue. The prepuce is the fold of skin covering the glans.
Category: Male Ducts and Glands
Question 6
Which region of a sperm cell is packed with mitochondria that supply ATP for movement?
Acrosome
Midpiece
✓
Head
Neck
Correct Answer
Midpiece
The midpiece is wrapped with mitochondria that generate the ATP powering the tail. The acrosome is an enzyme-filled cap over the nucleus used to penetrate the egg's coverings. The head holds the haploid nucleus. The neck is a short connecting region between the head and the midpiece.
Category: Spermatogenesis
Question 7
Which anterior pituitary hormone acts on Sertoli cells to promote spermatogenesis?
Luteinizing hormone
Prolactin
Follicle-stimulating hormone
✓
Gonadotropin-releasing hormone
Correct Answer
Follicle-stimulating hormone
Follicle-stimulating hormone binds Sertoli cells and stimulates them to support sperm production. Luteinizing hormone targets Leydig cells to trigger testosterone release. Prolactin is mainly involved in milk production. Gonadotropin-releasing hormone comes from the hypothalamus, not the anterior pituitary.
Category: Testicular Hormones
Question 8
Primary oocytes formed before birth remain arrested in which stage of meiosis until shortly before ovulation?
Metaphase II
Anaphase I
Telophase II
Prophase I
✓
Correct Answer
Prophase I
Primary oocytes begin meiosis during fetal life and pause in prophase I, resuming only shortly before that oocyte is ovulated, which can be decades later. Metaphase II is where the secondary oocyte pauses after ovulation until fertilization. Anaphase I is a brief stage of the first division with no prolonged arrest. Telophase II occurs only after meiosis II resumes.
Category: Oogenesis and Follicles
Question 9
In which region of the uterine tube does fertilization usually take place?
Ampulla
✓
Infundibulum
Isthmus
Fimbriae
Correct Answer
Ampulla
The ampulla is the wide middle segment of the uterine tube and is the usual site where sperm meet the oocyte. The infundibulum is the funnel-shaped end near the ovary that receives the oocyte. The isthmus is the narrow segment joining the uterus. Fimbriae are fingerlike projections that sweep the oocyte into the tube.
Category: Female Reproductive Anatomy
Question 10
What hormonal event directly triggers ovulation in the middle of the ovarian cycle?
A drop in progesterone
A surge in luteinizing hormone
✓
A rise in inhibin
A surge in prolactin
Correct Answer
A surge in luteinizing hormone
A sharp spike in luteinizing hormone causes the mature follicle to rupture and release the secondary oocyte. A drop in progesterone triggers menstruation rather than ovulation. A rise in inhibin suppresses FSH. A surge in prolactin is linked to milk production, not ovulation.
Category: Ovarian and Uterine Cycles
Question 11
After ovulation, which structure forms from the ruptured follicle and secretes progesterone?
Corpus albicans
Primary follicle
Corpus luteum
✓
Granulosa layer
Correct Answer
Corpus luteum
The remnants of the ruptured follicle become the corpus luteum, which secretes progesterone and some estrogen during the luteal phase. The corpus albicans is the nonfunctional scar left when the corpus luteum degenerates. A primary follicle is an early developing follicle that has not ovulated. The granulosa layer is part of a growing follicle before ovulation.
Category: Ovarian and Uterine Cycles
Question 12
Which layer of the endometrium is shed during menstruation?
Stratum basalis
Myometrium
Perimetrium
Stratum functionalis
✓
Correct Answer
Stratum functionalis
The stratum functionalis thickens under hormonal influence each cycle and sloughs off during menses when progesterone falls. The stratum basalis is the deeper layer that stays in place and regenerates the functionalis. The myometrium is the smooth muscle layer of the uterine wall. The perimetrium is the outer serous covering of the uterus.
Category: Ovarian and Uterine Cycles
Question 13
During which phase of the uterine cycle does rising estrogen rebuild the endometrium after menses?
Proliferative phase
✓
Menses
Secretory phase
Luteal phase
Correct Answer
Proliferative phase
In the proliferative phase, estrogen from growing follicles stimulates the endometrium to regrow and thicken, ending around ovulation. Menses is the shedding phase. The secretory phase follows ovulation and is driven mainly by progesterone. The luteal phase is a stage of the ovarian cycle, not the uterine cycle.
Category: Ovarian and Uterine Cycles
Question 14
What acellular glycoprotein layer lies directly around the oocyte in a developing follicle?
Corona radiata
Zona pellucida
✓
Theca interna
Tunica albuginea
Correct Answer
Zona pellucida
The zona pellucida is a clear glycoprotein coat secreted around the oocyte, and sperm must pass through it to fertilize the egg. The corona radiata is a layer of granulosa cells outside it. The theca interna is a layer of hormone-secreting cells just outside the granulosa cells, beneath the theca externa. The tunica albuginea is the fibrous capsule of the ovary or testis.
Category: Oogenesis and Follicles
Question 15
Which glands on either side of the vaginal opening secrete mucus that keeps the vestibule moist?
Areolar glands
Sebaceous glands
Greater vestibular glands
✓
Sweat glands
Correct Answer
Greater vestibular glands
The greater vestibular glands, also called Bartholin's glands, release mucus into the vestibule to keep it moist. Areolar glands lubricate the skin around the nipple. Sebaceous glands release oily sebum onto hair and skin. Sweat glands produce sweat for cooling.
Category: Female Reproductive Anatomy
Question 16
Which cells in the mammary gland contract to push milk out of the alveoli toward the nipple?
Alveolar cells
Adipocytes
Granulosa cells
Myoepithelial cells
✓
Correct Answer
Myoepithelial cells
Myoepithelial cells surround the milk-producing alveoli and contract, in response to oxytocin, to move milk into the ducts. Alveolar cells secrete milk but do not eject it. Adipocytes are fat cells that largely determine breast size. Granulosa cells are found in ovarian follicles.
Category: Female Reproductive Anatomy
Question 17
Which gene on the Y chromosome starts the cascade that directs the embryonic gonads to become testes?
SRY
✓
HOX
BRCA1
XIST
Correct Answer
SRY
The SRY gene, the sex-determining region of the Y chromosome, switches on genes for testis development and suppresses female pathways. HOX genes pattern the body axis. BRCA1 is a tumor-suppressor gene involved in DNA repair. XIST is an X chromosome gene involved in X inactivation.
Category: Reproductive Development
Question 18
Which embryonic duct, also called the Wolffian duct, develops into the male duct system under the influence of testosterone?
Paramesonephric duct
Mesonephric duct
✓
Pronephric duct
Vitelline duct
Correct Answer
Mesonephric duct
The mesonephric duct is stimulated by testosterone to form the epididymis, ductus deferens and seminal vesicles. The paramesonephric duct is the Mullerian duct that forms female internal structures and degenerates in males. The pronephric duct belongs to the earliest, transient kidney stage. The vitelline duct connects the embryonic gut to the yolk sac.
Category: Reproductive Development
Question 19
Which hormone secreted by adipose tissue appears to play a strong role in determining the timing of menarche?
Ghrelin
Insulin
Leptin
✓
Melatonin
Correct Answer
Leptin
Leptin is released by fat cells, and adequate levels appear necessary for puberty and the first menstrual period to begin, linking body fat to reproductive timing. Ghrelin is a stomach hormone that stimulates hunger. Insulin is a pancreatic hormone that lowers blood glucose. Melatonin is a pineal hormone tied to sleep and circadian rhythm.
Category: Reproductive Development
Question 20
Which skeletal muscle in the spermatic cord pulls the testes closer to the body when the environment is cold?
Dartos muscle
Bulbospongiosus muscle
Levator ani muscle
Cremaster muscle
✓
Correct Answer
Cremaster muscle
The cremaster muscle is skeletal muscle in the spermatic cord that elevates the testes to conserve heat and relaxes to lower them when warm. The dartos muscle is smooth muscle in the scrotal wall that wrinkles the skin. The bulbospongiosus muscle surrounds the base of the penis and aids ejaculation. The levator ani muscle forms much of the pelvic floor.
Category: Male Ducts and Glands