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Male Reproductive System. Path and Production of Sperm. Testes - olive size (1-1.5in) Divided into lobules Lobules contain 1-4 seminiferous tubules Between seminiferous tubules are interstitial cells Interstitial cells produce androgens = testosterone
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Path and Production of Sperm • Testes- olive size (1-1.5in) • Divided into lobules • Lobules contain 1-4 seminiferous tubules • Between seminiferous tubules are interstitial cells • Interstitial cells produce androgens = testosterone • Sperm leave S.F.T. to go into epididymus.
Lobules Atrophied Testes: Alcoholism, Mumps Normal
Inside the seminiferous tubules seminiferous tubules Spermatozoa Cells
The path continues…. • Epididymus • 20 ft. coiled on posterior lateral side of testis • Use: temporary storage of immature sperm. • Sperm travel approximately 1 ft a day • Sperm gain ability to swim at the end • When stimulated male epididymus contracts to expel sperm into the vas deference.
The long and windy road… • Vas Deferens • Runs up epididymus into pelvic cavity • Arches over bladder • Empties into ejaculatory duct. • Vasectomy = vas deference is cut or cauterized. • Sperm produced but reabsorbed • Testosterone still produced. Sex drive and characteristics remain the same. Pregnancy & Reproductive Vasectomy
Still traveling…. • Ejaculatory duct- (ejac to shoot forth) • Passes through prostate gland • Merges with urethra • Moves sperm through peristaltic waves.
The road has an end. • Urethra • Sperm are ejaculated through it • Urine and sperm can’t travel at the same time • Bladder sphincter constricts when sperm ejaculates.
Accessory Glands • Seminal Vesicle • 60% of semen • Thick and Yellow • Sugar nourishes • Vitamin C activates sperm • Excretes into the ejaculatory duct
Extra Accessories • Prostate Gland • Chestnut size and shape • Below bladder, anterior to rectum = milky fluid activates sperm • Examined by rectal exam • Problem- • Hypertrophy of prostate strangles the urethra,causes bladder infections and difficulty urinating. • Cures: Balloon method, radiation, drugs
Prostate Location (Right) and enlarged prostate (L). Should be 3-4 cm.
How the problem effects the male urinary system: • Prostate Gland • 3 lobes enlarged • Caused a stone to form in the bladder. Prostate Cancer Biopsy & Removal This one Talks
Even more Accessories… • Bulbourethral Glands • Pea-sized inferior to prostate • Secrete thick clear mucous • 1st secretion. • Jobs • Cleanses urethra and removes acidic traces of urine • Lubricant during sexual intercourse
Semen • Alkaline pH 7.2-7.6 • Neutralizes vaginal pH of 3.5 • Dilutes sperm – increasing sperm motility • Approximately 1 tsp (5ml) of fluid ejaculated with 50-130 million sperm in each ml.
Sperm Production • Spermatogenesis. • Starts in puberty when FSH is secreted by the anterior pituitary. • Primary spermatocytes then go through meiosis. (4 sperm are made) • Takes 64-72 days to make sperm • 23 Chromosomes = Haploid. Spermatogenesis
Infertility • Diagnosed by semen analysis. • Check sperm count, motility, and morphology • Less than 20 million sperm/ml- infertile • Threats to sperm = • Antibiotics- suppress sperm formation • Radiation, pesticides, lead, pot, tobacco, heat Pregnancy & Reproductive Impotence
External Genitalia • Scrotum • Job to decrease temp. to keep sperm viable • Changes in scrotal surface area depending on Temp. • Penis or ‘tail’ • Urethra is surrounded by three tubes of erectile tissue • Fill with blood when excited = erection
Testosterone Production • Interstitial cells- activated by lutenizing hormone (LH) of the pituitary • Produce Testosterone = secondary sex characteristics • Deep Voice from enlarged larynx • Increased hair growth • Heightened skeletal muscle and bone size
Parts of the sperm Acrosome: Cap of the sperm. Has a Lysosome to eat into the egg. Head: Contains DNA/ Chromosomes Midpiece is full of mitochondria to make ATP for sperm movement. Tail: Used to move sperm.