1. Reproductive System
Male

2. Comparison of Male and Female Reproductive Systems
Spermatogenesis
Occurs throughout life from puberty to ?
Primary sex organ is the testes
Primary male sex hormone is testosterone
Oogenesis
Begins at puberty ends at menopause
Women are born with all the gametes they will ever have
Primary sex organ is the ovary
Several hormones, estrogen, progesterone.

3. Male Reproductive System Principal Structures
Testes
Epididymis
Ductus deferens (vas deferens)
Urethra
Ejaculatory duct
Prostate gland (1)
Seminal vesicle (2)
Bulbourethral gland (2)

4. Male Reproductive System

5. Position of Testes Testes are located in the scrotum
Spermatic cord contains the ductus deferens, as well as several arteries and veins
Contractions of the DARTOS muscle in the scrotum gives the scrotum its wrinkled appearance
The CREMASTER muscle can pull the testes closer to the body, also regulates testes position for optimum sperm production in relation to temperature

6. Male Reproductive System

7. Structure of Testes
Testes are divided into lobules by the tunica albuginea
There are lobules containing 1-3 coiled seminiferous tubules
Sperm production occurs in the seminiferous tubules

10. Spermatogenesis

11. Spermatogenesis Production of sperm
Occurs in the seminiferous tubules of the testes
Stimulated by testosterone - produced by the interstitial cells
Testosterone production is stimulated by luteinizing hormone (LH)

12. Seminiferous Tubules and Interstitial Cells (Leydig cells)

13. Sustentacular cells (Sertoli cells) and Spermatogenesis

14. Spermatogenesis

15. Epididymis Coiled tubules adjacent to the testes Stores sperm
Recycles damaged sperm
Adjusts composition of tubular fluid

16. Ductus Deferens
Sperm carrying tube that begins at the epididymis and ends at the prostate gland
16-18 in long
Runs in the spermatic cord
Joins with the seminal vesicles to form the ejaculatory duct
Epithelial lining of pseudostratified columnar cells with apical sterocilia

17. Histology of the Ductus Deferns

18. Ductus Deferens Epithelial lining

19. Ductus Deferens, Seminal Vesicles, Prostate, and Bulbourethral glands

20. Seminal Vesicles Accessory gland Contribute 60% of the volume of semen
Viscous, whitish-yellow alkaline fluid
Seminal secretion contains fructose
Sperm use this sugar to make ATP
Sperm become motile when mixed with this fluid
Prostaglandins also in the secretion
Promotes widening and slight dilation of cervix to allow sperm entry into the uterus

21. Prostate Gland Small gland at the base of the bladder
Encircles the prostatic urethra as it leaves the bladder
Prostatic fluid contributes 20-30% of the volume of semen
Weakly acidic secretion to protect the sperm in the acidic female vagina.
Seminalplasmin - antibiotic that helps prevent urinary tract infections in males

22. Bulbourethral Glands Located at base of penis
Secrete a thick, sticky, alkaline mucus
Helps neutralize urinary acids

23. Semen Sperm – 20-100 million/ml
Seminal fluid – the fluid component of semen
60% from seminal vesicles
30% from prostate
5% from bulbourethral gland
5% from sustentacular cells and epididymis
Enzymes
Total volume 2-5ml – 99% of the volume of semen is added from accessory glands

24. Composition of semen Sperm – gamete – seminiferous tubules
Mucus – lubricant – bulbourethal gland
Water – liquid medium – all glands
Buffers – neutralize vaginal acid – prostrate, bulbourethral glands
Fructose – nourish sperm – seminal vesicle
Citric acid – nourish sperm – prostate
Vitamin C – nourish sperm – seminal vesicle
Carnitine – nourish sperm – epididymis
Enzymes – clot and liquefy semen – seminal vesicle, prostate
Zinc – fertility? – unknown
Prostaglandins – sperm transport – seminal vesicles

25. Urethra
Prostatic urethra
Membranous urethra
Penile urethra

26. Penis

27. Penis

30. Sildenafil citrate (Viagra)
How stuff works
Sildenafil citrate
(Viagra)