Male Reproductive System PDF

1. Production and transport of male sperm cells 2. Production of male hormones like testosterone GONADS: - Male- testis - Female - ovary 1. Scrotum - wrinkled sac containing testis, epididymis, and vas deferens - dartos muscle - regulates testicular temperature -...

1. Production and transport of male sperm cells 2. Production of male hormones like testosterone GONADS: - Male- testis - Female - ovary 1. Scrotum - wrinkled sac containing testis, epididymis, and vas deferens - dartos muscle - regulates testicular temperature - cold temperature- testis gets closer to the body - warm temperature- testis hangs loosely - spermatogenesis requires 2-3 °C lower than body temperature 1. Body- made up 3 erectile tissues a. corpora cavernosa - 2, dorsolateral, vascular spaces b. corpus spongiosum - contains spongy urethra 2. Root-proximal a. bulb- expanded proximal portion of corpus spongiosum. Covered by bulbospongiosum b. crura- proximal tapered parts of corpora cavernosa. Covered by ischiocavernosum - expanded distal end of corpus spongiosum - distal terminal urethra is expanded called fossa navicularis - prepuce and frenulum 1. Testis - intra-abdominal during fetal life - descends and covered by tunica vaginalis from peritoneum - deep covering tunica albuginea - divides the testis into lobules - each lobules contains seminiferous tubule 1. Spermatogenic cells - grow and mature to form mature sperm cells 2. Sertoli cells/sustentacular cells - support and protect sperm cells 3. Interstitial cells of leydig - secrete testosterone - located in between seminiferous tubules A. Epididymis - comma shaped, 4cm long, located posterior to the testis, with ff parts, head, body and tail - tail is continuous with vas deferens Functions: 1. Site of sperm maturation- mobility and capability to fertilize an ovum( 10-14 days) 2. Storage of sperm cells 3. Propel sperm cells to vas deferens - Continuation of epididymis - 45cm long - Passes through the inguinal canal and enter the pelvic cavity - Joins the duct of seminal vesicle to form ejaculatory duct 1. Storage of sperm cells 2. Conveys sperm cell from epididymis to ejaculatory duct and urethra 3. Reabsorbed not ejaculated sperm cells 1. Male urethra 20cm a. Prostatic (2-3 cm) - widest, most dilatable b. Membranous (1 cm ) - traverses urogenital diaphragm, shortest and least dilatable c. Penile (15-20 cm) - longest, traverses corpus spongiosum 1. Prostate gland - located beneath urinary bladder with 5 lobes - surround prostatic urethra - secretes milky, slightly acidic pH 6.5 seminal fluid 1. Citric acid- for ATP energy of sperm cells 2. Acid phosphatase 3. Proteolytic enzyme- breaks down clotting protein - Located postero- inferior to urinary bladder - 5cm long - Convoluted pouch - 60% of semen volume - Secretes fructose 1. Alkaline viscous fluid - neutralizes acidic environment of vagina and male urethra - contains fructose for energy source of sperm cells 2. Prostaglandin - mobility and sperm viability - stimulate smooth muscle contraction of female 3. Clotting protein - coagulate sperm after ejaculation - Located within the urogenital diaphragm on either side of membranous urethra - opens into penile urethra Secretions: 1. Alkaline fluid 2. Mucus- lubricates penis and lining of urethra - volume- 2.5- 5ml with 50-150million sperm cells/ml appro 300-500millions sperm - Slightly alkaline 7.2-7.7 - Contains seminal plasmin destroys certain bacteria - Once ejaculated sperm coagulates in 5min due to clotting protein from seminal vesicle - About 10-20min liquefies due to prostate specific antigen(PSA) and other proteolytic enzymes from prostate 1.Seminal fluid - secretion from glands - prostate gives milky white, seminal vesicle and bulbourethral gland sticky appearance 2. Sperm – 70um, viable in 72hrs Sperm cells A. Head 1. Acrosomes with lysosomal enzymes for penetration of zona pellucida of 2° oocyte 2. nucleus- with 23 chromosomes haploid number B. Mid piece- with mitochondria C. tail- flagella for motility - Enlargement and stiffening of the penis - Due to tactile, visual, auditory, olfactory and imagination reaches erection center in hypothalamus--- sends parasymphathetic nerve impulses into the penis---vasodilatation of helicine arteries into the penis- erection - Powerful expulsion of semen from the urethra to the exterior --- due to sympathetic reflex--- closure of smooth muscle sphinter at the base of urinary bladder- peristaltic contraction of the male reproductive tract - Discharge of small volume of semen before ejaculation - May occur during sleep, nocturnal emission - Due to peristaltic contraction of male reproductive tracts - Undescended testis - 80% will spontaneously descend during 1 year of life - May result to sterility and testicular cancer Circumcision THANK YOU VERY MUCH AND STUDY WELL!