Male Reproductive Anatomy and Spermatogenesis - Anatomy and Physiology
- Which cells form the blood-testis barrier and nourish developing sperm under the influence of FSH?
- Sustentocytes (Sertoli cells), joined by tight junctions inside the seminiferous tubules.
- How many spermatozoa result from one primary spermatocyte?
- Four. Meiosis I gives two secondary spermatocytes, and meiosis II gives four spermatids that mature into sperm.
- Why are the testes located in the scrotum outside the abdominal cavity?
- Viable sperm production requires a temperature about 3 degrees C below core body temperature.
- In which duct do sperm mature, gain the ability to swim and get stored?
- The epididymis.
- Which cell division converts a primary spermatocyte into two secondary spermatocytes?
- Meiosis I, which reduces the cells from diploid to haploid.
- Which accessory gland surrounds the urethra just below the bladder and secretes a milky fluid containing PSA and citrate?
- The prostate gland.
- After leaving the epididymis, which duct carries sperm up through the inguinal canal toward the ejaculatory duct?
- The ductus (vas) deferens. It joins the duct of the seminal vesicle to form the ejaculatory duct.
- Where in the testis does spermatogenesis take place?
- In the seminiferous tubules.
- What is spermiogenesis?
- The maturation of spermatids into sperm without division: the Golgi forms the acrosome, a flagellum grows and excess cytoplasm is shed.
- Which testicular cells produce testosterone in response to LH?
- Interstitial (Leydig) cells, located between the seminiferous tubules.
- Which accessory gland contributes the largest share of semen volume, including fructose for sperm energy?
- The seminal vesicles, which provide most of the semen volume.
- Which hormone do Sertoli cells secrete to reduce FSH release?
- Inhibin, which acts by negative feedback on the anterior pituitary.