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The Reproductive System. Chapter 16. ___________________- primary sex organs - ie . Testes and ovaries _______________________--sex cells produced by gonads as well as gonads secrete sex hormones _______________________________-remaining reproductive structures
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The Reproductive System Chapter 16
___________________-primary sex organs-ie. Testes and ovaries • _______________________--sex cells produced by gonads as well as gonads secrete sex hormones • _______________________________-remaining reproductive structures • Joint purpose of Reproductive system is produce offspring---via sperm in males and ___________ in females Accessory reproductive organs gametes gonads ova
Anatomy of Male Reproductive System • Testes have exocrine-sperm producing- function and endocrine-testosterone producing • Accessory structures in delivery of sperm to exterior or to female
TESTES- Tunica albuginea • Plum shaped---4 cm –sized surrounded by fibrous connective tissue capsule-_____________________________-“white coat” • Extensions of capsule extend into testes and divide into wedge-shaped ______________________each containing 1-4 _____________________________-sperm producing portion lobules Seminiferous tubules
Seminiferous tubules empty into another set of tubules---____________________on each side of testis-sperm travel from rete to enter 1st part of duct system-____________________-hugging external testis • In soft tissue around seminiferous tubules are -__________________-that produce androgens-esp. testosterone---thus different tissue process sperm and then hormones Rete testis epididymis Interstitial cells
DUCT SYSTEM-inc.edididymis,ducusdeferns, and urethra • A.___________________________-highly coiled tube-~6 m-capping superior testis and extends posterolaterally-temporary storage for immature sperm entering from testis • Takes sperm about _____________days to travel epididymis,maturing along the way...and become motile • During ejaculation,epididymis contracts to expel ___________into--_________________________________ 20 epididymis Sperm….ductus deferens
. Ductus Deferens(= vas deferens)-extends upward from epididymis through inguinal canal,to pelvic cavity and arches over superior bladder…enclosed w/ blood vessels and nerves and connective tissue sheath-______________________ and it travels up through inguinal canal Spermatic cord
Loops medially over ureter and goes down posterior bladder-expands as ampulla and empties into _________________--this passes through prostate gland and merges w/ urethra • Main function of ductus deferens is to _________________________ • At ejaculation smooth muscle squeeze sperm forward by ___________________ Propel live sperm from storage-epididymis and distal vas deferns Ejaculatory duct peristalsis
A __________________________________is a contraceptive procedure that ligates-“ties-off” ducusdeferns in part that lies in scrotum---sperm are still produced-but don’t reach body exterior and are phagocytized-rendering male sterile vasectomy
Urethra • From base bladder to tip of penis-terminal feature of male system-carries urine and sperm-however both never travel @ same time---bladder sphincter constricts @ ejaculation preventing this • 3 regions: 1) ______________-surrounded by prostrate • 2)_____________-from prostatic urethra to penis and 3)__________-runs length of penis Prostatic urethra Membranous urethra Spongy (penile)urethra
ACCESSORY GLANDS AND SEMEN -inc. paired seminal vesicles,singleprostate,bulbourethral glands and semen • A.____________________@ base of bladder make ~60% of seminal fluid-secretion rich in _________________which nourish and activate sperm • Each of its duct joins vas deferens on same side to form __________----thus sperm and seminal fluid enter urethra during ejaculation Fructose, vitamin C, proglastins… Seminal vesicles Ejaculatory duct
Prostate-single doughnut –shaped gland-encircles prostatic urethra below bladder • Its glandular , milky secretion helps activate sperm---during ejaculation-fluid enters urethra through several small ducts • Since near rectum,can be palpitated rectally
Older men suffer hypertrophy of gland, strangling urethra-making urination difficult and increases risk of bladder infections-________________ and kidney damage • Treatments include :surgery,drugs or microwaves to shrink prostate,insertion of small balloon to push prostate away from urethra,incineration w/low energy radiation • ___________________-inflammation of prostate-common • _______________-most prevalent cancer in men-slow growing,usually cystitis prostatitis Prostatic cancer
C. _______________________-tiny pea-sized glands posterior to prostate, produce thick,clearmucus draining into penile urethra----is 1st secretion to pass upon sexual arousal ---functions in cleansing urethra of acidic urine and is a sexual lubricant Bulbourethral glands
D. Semen-milky white, somewhat sticky mixture of sperm and gland secretions ;transport medium for nutrients and chemicals that protect and aid in movement of sperm • Sperm have little cytoplasm or stored nutrients so __________________ is energy fuel • pH ~ 7.2-7.6 helps neutralize acidic vagina(3.5-4.0)-protecting sperm(sperm are sluggish in acidic environment) • ________________-antibiotic chemical destroying certain bacteria • Hormone_______________-…………………………. fructose seminalplasmin relaxin
Semen cont’d • Enzymes to enhance sperm motility • Substances to inhibit female reproductive immune response • Male infertility---causes include obstruction of duct system, hormone imbalance , environmental estrogens ,pesticides, too much alcohol….often _________________is checked to analyze sperm count, motility, and morphology,semen volume ,pH, fructose amount…sperm count should not be below 20 million /mL Semen analysis
EXTERNAL GENITALIA-ie. Scrotum and penis • Scrotum-divided sac of skin outside abdominal cavity, normally hangs loosely, rendering testes temperature below body temp.( @ ~ 5.4 degrees lower)-necessary for healthy sperm production ,changes in scrotal surface area help maintain temp—example -wrinkles as pulls toward body during external cold temp’s • Penis-delivers sperm-consists of shaft ,glans penis tip and prepuce or foreskin-loose skin covering-often removed at circumcision/Internally-spongy urethra SURROUNDED by 3 elongated areas of _______________________that fill w/ blood during arousal-causing rigid erection Erectile tissue
Male Reproductive Functions • Spermatogenesis=sperm production-begins @ puberty and is lifelong • Millions/day • _________________primitive stem cells @ periphery of each seminiferous tubule/rapid mitotic division to build stem cell line….from birth to puberty spermatogonia
Follicle-stimulating hormone Spermatogeneisis cont’d • @ puberty _______________________(FSH) is secreted in increasing amounts by ant. Pituitary gland…from here on out ,each division produces 1 stem cell-type A daughter ---which remains @ tubule periphery to maintain stem population…and 2nd,type B daughter-pushed toward tubule lumen to become primary spermatocyte and will undergo MEIOSIS • Gametes @ this stage are called _______-made by meiosis and have ½ genetic material (2n in humans=23 x 2) • As meiosis occurs ,primary,thensecondary spermatocytes pushed toward tubule of lumen • Spermatids NOT functional sperm-nonmotile and excess cellular baggage spermatids
Spermatogenesis cont’d • During last stage-_______________-excess cytoplasm sloughed off and now have _________________________,equipped w/high metabolism and motility • Sperm head has DNA---essentailly nucleus • Anterior to head is ______________made by golgi and similar to large lysosome---which breaks down @ membrane and releases to help sperm penetrate follicle of egg Mature sperm compacted into 3 regions-head,midpiece and tail Acrosome-helmutlike
Spermatogenesis cont’d • Filaments make long tail from centriloes in midpiece w/mitochondria wrapped around for necessary ATP • All of spermatogenesis-from primary spermatocyte to release of immature sperm takes 64-72 days • Sperm in lumen nonmotile and can’t fertilize….moved by peristalsis from tubules into epididymis---there further maturation and increased motility • Things that can alter sperm formation:________________- Some antibiotics,radiation,lead,somepesticides,marijuana,tobacco, excessive alcohol
Testosterone production • produced by intersitial cells • @ puberty FSH prods sperm production and ________________(LH) is also released by anterior pituitary on from here on out testosterone is produced continuosly,rising levels responsible for secondary sexual characteristics:___________________-testosterone not produced and secondary sex characteristics not produced_____________….castration will cause this or malfunction of interstitial cells…also cause sterility Deeping voice,increased hair all over most of body-esp. axillary and pubic;skeletal muscle enlargement-more muscle mass;increased bone growth and density of bone Luteinizing hormone Sexual infantilism
FeMALE REPRODUCTIVE ANATOMY • function in producing gametes(ova) and nurture/protect developing fetus • _____________________primary reproductive organs-both exocrine and endocrine in nature ovaries
Ovarian follicles Follicle cells OVARIES • Shape of almonds but about twice as large • Internally __________________-each consisting of an immature egg-oocyte-surrounded by 1 or more layers called __________ • As developing egg matures follicle enlarges and produces fluid filled antrum-At this point follicle is called vesicular or _________________follicle,which is mature and ready to released during ____________________. • After ovulation,ruptured follicle is transformed into ___________________--“yellow body”,which degenerates Graafian follicle ovulation Corpus luteum
Ovarian follicle Follicle cells
Ovaries cont’d Ovarian ligaments • Ovulation ~ every 28 days….in older women ovaries are scarred and pitted from release of many eggs • Ovaries secured to lateral pelvis by _________________and medially by ______________and in between held by fold of peritoneum-broad ligament Suspensory ligaments
DUCT SYSTEM-uterine tube,uterus and vagina • Fallopian(uterine) tubes—internal duct system • receive ovulated oocyte and provide fertilization site • each about 4” long,extends medially from ovary to empty in superior uterus • enclosed and supported by broad ligament
Fallopian tubes cont’d • little or no contact between fallopian tubes and ovaries-instead contact @ distal end is by funnel-shaped ____________________that has fingerlike projections-fimbriae that surround ovary-- WHICH create fluidlike current that carries oocyte into fallopian tube---to thus journey to uterus • At this point is where many potential eggs are lost in peritoneal cavity • Cilia and peristalsis move oocyte along to uterus-taking about 3-4 days,but egg is viable ~24 hrs. after ovulation,sofertilization is usually in fallopian tube • To reach oocyte,sperm must swim up through vagina and uterus to fallopian tubes---swimming against a downward beat of Cilia! infundibulum
Fallopian tubes cont’d Pelvic inflammatory disease • Because fallopian tubes and ovaries are not physically continuous,this makes this area vulnerable to infection,such as bacteriaof Gonorrhea…maybe causing __________________which can cause scarring and closing of tubes
Uterus-located in pelvis between bladder and rectum • Hallow/functions to receive,retain,and nourish a fertilized egg • About the size and shape of a pear in women who haven’t been pregnant • Suspended by broad ligament and anchored by round and uterosacral ligaments • _________________=main portion • _________________-superior,rounded region above fallopian tube entrance fundus body
Uterus cont’d • ______________-narrow outlet into vagina below • Wall is thick w/3 layers:1)inner mucosa-________________-At implantation-fertilized egg burrows here/This layer sloughs off during ________________-menstruation every 28 days-- if not fertilized • 2)______________-interlacing bundles of smooth muscle making bulky middle layer-contracts during labor 3) perimetrium-outer serous layer(visceral peritoneum cervix endometrium menses myometrium
__________________________________-common in women 30-50-risks factors inc. cervical inflammation,STDs,multiplepregnancies,promiscuity/detected w/Pap smear/slow growing ,usually Cervical cancer
Vagina-thin-walled tube 3-4”long/between bladder and rectum from cervix to body exterior=birth canal./also organ of copulation • Distally partially enclosed by __________mucosa-which is very vascular and bleeds when ruptured hymen
External genitalia=vulva • monspubis-fatty,rounded area overlying pubic symphysis-hair after puberty • laterally are 2 skin folds w/hair-labia majora (encloses vestibule which houses external urethra opening and vagina)and l.minora • ______________ surround vagina and secretes for distal vagina • Clitoris-small protrusion that is corresponding to penis w/erectile tissue but no reproductive duct • ___________________-between ant. labial folds,anus and ischialtuberosities Greater vestibular glands perineum
FEMALE REPRODUCTIVE FUNCTIONS AND CYCLES • OOGENESIS AND THE OVARIAN CYCLE • Females’ reproductive ability begins at puberty and ends around 50’s(menopause) • In developing female fetus,_________-female stem cells multiply rapidly to increase their numbers,then daughter cells-primary oocytes-push into ovary connective tissue and primary follicle forms around them • By birth,oogonia cease to exist and a lifetime supply of primary oocytes are in place---waiting 10-14 years to undergo MEIOSIS! • @ puberty , ant. Pituitary produces_________FSH-stimulates a small # of primary follicles to grow and mature each month and then ovulation occurs monthly….constituting the _________cycle oogonia Follicle-stimulating hormone ovarian
Oogenesis and ovarian cycle cont’d • @ puberty ~ 250,000 oocytes remain w/ a small # activated each month….appx 500 of the 250,000 ova are released in the limited # of years of fertility • The FSH prods the follicle to enlarge ,accumulating fluid in central antrum/Primary oocyte replicates chromosomes and MEIOSIS occurs-producing 1 ________________and polar body • Follicle development to the point of rupture takes about 14 days with ___ovulation________________ occurring at just about this time • Ovulation occurs at the response to _luteinizing hormone__LH • Secondary oocyte is still surrounded by follicle cell capsule now called_coronaradiata(“radiating crown”)…abdominal pain can accompany this-mittelschmerz Secondary oocyte