1 Male Reproductive System
2 Basic Anatomy Testes (gonads) Encased within scrotum and stored outside body Scrotum expands and contracts to heat and cool the testes keeping them at a temp. slightly less than body temp This is the optimal temp for sperm formation. Seminiferous Tubules 250 m long network of highly coiled tubes within testes which produce sperm Epididymis Extension of sem. tubules, where the sperm are stored and reach final maturation
Basic Anatomy Penis Delivery mechanism for sperm – also part of urinary tract Vas Deferens Sperm duct – how sperm get from the epidymis to the urethra Urethra shared with urinary tract; allows sperm to move through the penis Several glands will add liquids to the sperm to form semen Seminal Vesicle Injects fructose for energy Prostate Gland Injects an alkaline (basic) fluid which neutralizes acidity of vagina Cowpers Gland Injects a white mucous-like fluid which clumps the sperm together for a short period after ejaculation
Basic Anatomy – The Brain Pituitary Gland Hypothalamus
Basic Hormones GnRH - Gonaditropin Releasing Hormone Secreted by the hypothalamus (at the base of the brain next to the pituitary gland) Causes the pituitary gland to increase production of FSH and LH FSH - Follicle Stimulating Hormone Secreted by the pituitary gland Stimulates the cells in the testes to divide and become sperm Released constantly enabling males to produce around 400 million (estimates vary widely) sperm per day LH - Lutenizing Hormone Secreted by the pituitary gland Stimulates the testes to produce androgens (like testosterone) 5
A Natural Steroid Hormone Testosterone Secreted by the testes it stimulates The development of the penis and testes The deepening of the voice during puberty Muscle size and strength Bone growth and strength Sex drive (libido) Sperm production
What are illegal steroids? Steroids can be natural or synthetic and are often referred to as Anabolic substances – promote growth of skeletal muscle Androgenic substances – promote development of male sexual characteristics. Use of steroids can have severe and lasting side effects: Shrinking of the testicles Reduced sperm count/infertility and impotence Baldness Difficulty or pain in urinating Aggressive behaviors, rage or violence Severe acne Liver disease High cholesterol Anxiety Stunted growth (bones stop lengthening) Who is most likely to use steroids? Most steroid users are males between the ages of 11 and 18