Human Anatomy and Physiology Chapter 16-The Reproductive System Notes

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Human Anatomy and Physiology Chapter 16-The Reproductive System Notes

·  ______-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

·  Zygote becomes embryo and then fetus

I.  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

1.  TESTES-

·  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

·  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

2.  DUCT SYSTEM-inc. edididymis,ducus deferns, 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--______

B. 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

·  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 ______

·  A ______is a contraceptive procedure that ligates-“ties-off” ducus deferns in part that lies in scrotum---sperm are still produced-but don’t reach body exterior and are phagocytized-rendering male sterile

C. 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

3.  ACCESSORY GLANDS AND SEMEN-inc. paired seminal vesicles,single prostate,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

B. 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

C. ______-tiny pea-sized glands posterior to prostate,produce thick,clear mucus draining into penile urethra----is 1st secretion to pass upon sexual arousal ---functions in cleansing urethra of acidic urine and is a sexual lubricant

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______-

·  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

4. 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 by 3 elongated areas of ______that fill w/ blood during arousal-causing rigid erection

II.  Male Reproductive Functions

A.  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

·  @ 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,then secondary sprematocytes pushed toward tubule of lumen

·  Spermatids NOT functional sperm-nonmotile and excess cellular baggage

·  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

·  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:______-maybe producing 2 headed and/or multi-tailed sperm

B.  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

III.  FeMALE REPRODUCTIVE ANATOMY

·  function in producing gametes(ova) and nurture/protect developing fetus

·  ______primary reproductive organs-both exocrine and endocrine in nature

A.  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

·  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

B.  DUCT SYSTEM-uterine tube,uterus and vagina

1.  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

·  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,so fertilization 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!

·  Because fallopian tubes and ovaries are not physically continuous,this makes this area vulnerable to infection,such as bacterta of Gonorrhea…maybe causing ______which can cause scarring and closing of tubes

2.  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

·  ______-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)

·  ______-common in women 30-50-risks factors inc. cervical inflammation,STDs,multiple pregnancies,promiscuity/detected w/Pap smear/slow growing ,usually

3.  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

C.  External genitalia=vulva

·  mons pubis-fatty,rounded area overlying pubic symphysis-hair after puberty

·  laterally are 2 skin flods w/hair-labia majora (encloses vestibulewhich 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 ischial tuberosities

IV.FEMALE REPRODUCTIVE FUNCTIONS AND CYCLES

A.  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 tissueand 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

·  @ 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 bodies

·  Follicle development to the point of rupture takes about 14 days with ______occurring at just about this time

·  Ovulation occurs at the response to ______LH

·  Secondary oocyte is still surrounded by follicle cell capsule now called______(“radiating crown”)…abdominal pain can accompany this-mittelschmerz

·  1 developing follicle dominates each month/mature follicles not ovulated are overripe and deteriorate

·  Besides triggering ovulation each month,LH aso causes ruptured follicle to turn into corpus luteum(Both c.luteum and maturing follicle produce hormones)

·  If ovulated, secondary oocyte is penetrated by sperm in fallopian tube,THEN oocyte undergoes______making another polar body and ovum

·  ….its 23 chromosomes are combined w/23 of sperm in fertilized egg

·  If not fertilized, deteriorates

·  Polar bodies deteriorate

·  Sperm v. egg:-sperm relies mostly on surrounding for nutrients,while—egg larger and______-stocked w/ nutrients

B.  Uterine (Menstrual) Cycle

·  receptive to implantation only briefly---~ 7 days after ovulation

·  events of ______are cyclic changes that endometrium goes through monthly in response to ovarian hormone changes

·  Anterior pituitary ______hormones FSH and LH regulate Ovarian estrogen and progesterone

·  Typically cycle is 28 days w/ovulation occurring midway

·  3 stages:

1)______--superficial functional layer of thick endometrium is sloughed off-accompanied by 3-5 days bleeding---passing out vagina as menstrual flow/average blood loss 50-150mL(1/4-1/2 cup)….By day 5 ovarian follicles begin to produce estrogen

2)______---is stimulated by estrogen levels to cause basal layer of endometrium to regenerate ,glands form w/in and endometrial blood supply increases…endometrium restores to velvety,thick and well vascularized—ovulation @ end of this phase in response to LH

3)______-progestrone levels have risen(by corpus luteum) and act on estrogen charged endometrium and increase blood supply more/also increasing size of endometrial glands and begin supplying nutrients into uterine cavity to sustain an embryo until implanted

·  If fertilization does occur,embryo produces hormone similar to LH-causes ______

·  If fertilization does NOT occur,c. luteum degenerates and LH levels drop…This causes vessels supplying endometrium to go into spasms and kink—causing endometrial cells-deprived of O2 –to die ….setting stage for next menses

·  Cycle can vary from 21-40 days ,but time of ovulation is usually @ 14-15 days

C.  HORMONE PRODUCTION BY OVARIES

·  Begin @ puberty

·  Follicle cells of growing follicles produce______-causing the appearance of secondary sex characteristics :enlargement of fallopian tubes, vagina and external genitalia ;development of breasts ;axillary and pubic hair ;increased fat in hips and breasts and in general; Widening and lightening of pelvis; Onset of menses

·  Estrogen also has metabolic effects---ex-maintaing blood cholesterol(high HDL) and help Ca2+ uptake

·  Other ovarian hormone is ______made by c.luteum as long as LH is present in blood…stopping 10-14 days after ovulation/helps establish menses w/estrogen,but does NOT contribute to secondary sex traits…plays a role in pregnancy by inhibiting contraction of endometrium and prepares______(source of progesterone in pregnancy is placenta)

ovulation

V.MAMMARY GLANDS

·  In both sexes ,but has normal functions in female---being important only once reproduction is accomplished—stimulated to increase size by estrogen

·  Are actually modified sweat glands and part of integument ,in that sense….and anterior to pectoral muscles

·  ______-center pigmented area w/protruding nipple

·  Internally has 15-25 lobes radiating around nipple/lobes are padded and separated by connective tissue and fat

·  Within each lobe are smaller ______w/clusters of alveolar glands that ______-produce milk into lactiferous ducts opening via the nipple to the outside

·  ______-2nd most common cause of death in American women---1 in 8 developing this condition….~10% hereditary and half traced to BRCA 1 and 2 gene/80% of women w/ gene contract cancer---other risk factors inc. early menses,late menopause,estrogen replacement therapy….Breast cancer is signaled by change in skin texture ,puckering and nipple leakage…can be detected by self examination and by ______-X-rays that reveal tumors too small to feel(<1 cm.)