Lab # 10

1. Lab # 10 The Male Reproductive System Unit 12 (page 199) 1- Describe the anatomy of the internal and external male genitalia. 2- Describe the pathway taken by a sperm cell from its formation to its ejaculation, naming all the passages it travels. 3- Describe the composition of semen. 4- Describe the sequence of cell types in spermatogenesis, and relate these to the stages in meiosis.

2. The Reproductive System Main Reproductive Organs or Gonads Accessory Glands and Organs External Genitalia Duct System They produce secretions and release them into the duct system They produce gametes and hormones It receives and transport the gametes They participate in reproduction

3. The Male Reproductive System Main Reproductive Organs or Gonads Accessory Glands and Organs External Genitalia Duct System Seminal vesicles Epididymis Prostate gland Ductus Deferens Bulbourethral or Cowper’s Gland Ejaculatory Duct Urethra Testis Penis

4. Seminal vesicles Ductus (vas) deferens Ejaculatory duct Urethra Prostate gland Penis Bulbourethral gland Testis Scrotum Epididymis The Male Reproductive System

5. Testis Cremaster muscle Dartos muscle Scrotum 1: Testes and Scrotum It divides the scrotum into two compartments. Scrotal septum They contain the seminiferous tubes, which produce the sperm, and the Leydig’s cells, which produce testosterone. It pulls the testes closer to the body when the temperature decreases. Visceral layer Parietal layer It causes the wrinkling of the scrotum. It provides the proper temperature for normal sperm development. Tunica vaginalis

6. Ductus (vas) deferens Head of the Epididymis Efferent ductules Rete testis Seminiferous tubes Body of the Epididymis Ductus deferens Spermatic cord Blood vessels Nerves Lymphatic vessels (First part of the reproductive tract) They produce the sperm Tail of the Epididymis Visceral layer Tunica vaginalis Parietal layer

7. Route of Sperm from the Testes to the Exterior • Ductus (vas) deferens Urethra Ejaculatory duct Ejaculatory duct Reproductive tract • Ductus (vas) deferens Epididymis Epididymis Efferent ductules • Urethra Efferent ductules Rete testis Rete testis Sperm is produced in the seminiferous tubules Seminiferous tubule

8. Stem cells that divide to produce the spermatocytes. They protect the germ cells, promote their development, and produce the hormone inhibin. Nurse cells (Sertoli cells) Spermatogonia They produce the male sex hormones (androgens). Testosterone is the most important. Interstitial cells (cells of Leydig)

9. Ductus (vas) deferens 1- Monitoring and adjusting the composition of the seminiferous tubule fluid Epididymis Ampulla of the vas deferens 2- Recycling damaged spermatozoa 3- Storing, protecting, and facilitating the functional maturation of the spermatozoa Common ejaculatory duct 4- Transporting sperm to the ductus deferens 2: Epididymis and Ductus Deferens They are involved in the functional maturation, nourishment, storage, and transport of the sperm from testes to outside the body Seminal vesicle They propel the spermatozoa and fluid to the ejaculatory duct by way of peristaltic movement Urethra It carries the fluid and sperm into the urethra

10. Seminal vesicles Prostate gland Bulbourethral gland 3: Accessory Glands They produce bulk of semen, because the seminiferous tubes, and the epididymis only contribute 5% of the volume of the semen Produce a fluid that is viscous and alkaline and contains: 1- Fructose (nourishes the sperm), 2- Prostaglandins ( cause peristalsis in the reproductive tracts), and 3- Fibrinogen (forms a temporary clot in the vagina) It produces a milky and slightly acid fluid, which contains: 1- Seminalplasmin (antibiotic), 2- Acid phosphatase (activates the sperm), 3- Citric acid ( source of energy), and 4- Proteolytic enzymes (help the sperm move more easily by dissolving the substances surrounding it) It produces a thick alkaline mucous, which neutralizes and cleanses traces of acid urine in the urethra, and lubricates the tip of the penis

11. Corpora cavernosa Central artery Root Body Corpus espongiosum Spongy urethra Glans 4: The Penis It is the ejaculatory and copulatory organ that delivers the sperm into the vagina They are erectile bodies, which fill with blood and produce the erection It keeps the urethra open during ejaculation

12. 4: The Urethra Membranous urethra Prostatic urethra Spongy urethra

13. Gametogenesis and meiosis Nurse cells (Sertoli cells) Spermatogonia They protect and promote the development of the germ cell, and produce the hormone inhibin. Stem cells that divide to produce the spermatocytes. They produce the male sex hormones (androgens). Testosterone is the most important. Interstitial cells (cells of Leydig)

21. SPERMIOGENESIS: • It is the last step of spermatogenesis. Each spermatid matures into one spermatozoon (sperm). • They mature attached to the cytoplasm of nurse cells. SPERMIATION: • At spermiation, a spermatozoon loses the attachment to nurse cell and enters the lumen of seminiferous tubule. • From spermatogonial division to spermiation takes about 9 weeks.

26. Urinary bladder Seminal vesicle Prostate gland Ductus (vas) deferens Body of the penis Epididymis Testis Glans Scrotum

27. Urinary bladder Prostate gland Prostatic urethra Common ejaculatory duct Membranous urethra Spongy urethra Urogenital diaphragm Corpora cavernosa Corpus espongiosum

28. Urinary bladder Seminal vesicle Prostate gland Ejaculatory duct Corpus espongiosum Prostatic urethra Urogenital diaphragm Corpora cavernosa Spongy urethra

29. Ductus (vas) deferens Prostate gland Ampulla of ductus deferens Prostatic urethra Membranous urethra Common Ejaculatory duct Corpora cavernosa Urogenital diaphragm Spongy urethra Corpus espongiosum Bulbourethral or Cowper’s gland Epididymis Testis Urinary bladder