Exam 4 - The urinary system, the female reproductive system, and the male reproductive PDF

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The urinary system, the female reproductive system, and the male reproductive system ...

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The Urinary System Organs of the Urinary System: ● 2 kidneys = that filter blood and form urine ● 2 ureters = that transport urine from kidneys to urinary bladder ● Bladder = that temporarily stores urine ● Urethra = transports urine from bladder to exterior of body ○ External opening = “ external urethral orifice

Kidney ●

Size ○ Size of bar of soap ● Location ○ Just above waist ○ Right lower due to liver protected by lower ribs ● Hilus (Hilum) ○ Medial indented region, where ureter exit and vessels and nerves enter/exit ○ Only physical connection to rest of body ○ Inside hilum is a cavity called “renal pelvis” ■ Collects urine before it goes into ureter ■ renal pelvis narrows to form the ureter ● Retroperitoneal ○ Posterior to parietal peritoneum ○ Not in peritoneal cavity Three layers of CT that surrounds Kidneys 1. Renal capsule a. Fibrous CT, innermost, sac around kidney for protection, prevents spread of infection 2. Adipose Capsule ( perineal fat) a. Fat surrounding kidneys, shock absorber, holds kidneys in place laterally and below (middle layer) 3. Renal Fascia a. Sheet of CT that covers kidneys, holds kidney in place from falling forward, prevents spread of infection Renal Ptosis (nephroptosis) ● Kidneys drop down, out of normal position ● Caused by rapid weight loss b/c adipose capsule goes away ● Can obstruct or kink ureter causes urine to back up Hydronephrosis ● Excess urine (water) in kidneys ● causes kidney stones that block ureter ● Decreases the functional tissue in kidneys Internal Anatomy of Kidneys ● Outer cortex = granular appearance ● Inner medulla = has 8-18 triangle shaped “renal pyramids” striped appearance, tips

called “papillae” and point to renal pelvis ● Funnel-like extensions of renal pelvis surround papillae called “renal calyces” ● Urine formed in pyramids - papillae - calyces - renal pelvis - ureter Nephrons ● Functional units of kidneys, where urine is formed ● 1.3 million nephrons in each kidney and born with all of them (get bigger as age) ● 25% = show clinical problems ● Kidney enlarges and does 80% of work of two kidneys ● Composed of glomerulus and renal tubule Glomerulus ● Ball of capillaries, filter blood ● Afferent arteriole ○ Larger than efferent b/c it increases blood pressure for better filtration ● Glomerulus capillary wall is “fenestrated” (has pores in capillary wall) ● Surrounded by capillary basement membrane (filter paper) Renal Tubule ● collectes material filtered out of glomerulus and modifies it so mostly waste products = forms urine 1. Bowman’s capsule a. Cup-shaped structure surrounding glomerulus b. Collects material filtered out of glomerulus called “Filtrate” that eventually becomes urine c. Space between 2 layers is called “capsular space” d. Parietal layer of bowman’s capsule = one later of simple squamous epithelium e. Visceral layer = made of cells called “podocytes” that cling to capillary (glomerulus) f. Each had octopus arms with finger-like projections called “pedicles” which wrap around glomerulus g. B/w pedicles are spaces called “Filtration Slits” 2. Filtration Membrane a. Anything going from glomerulus (blood) into capsular space has to go across: i. Fenestrated (cap wall) ii. Capillary basement membrane iii. Filtration slits b. All three called “filtration membrane” c. Allows filtration based on molecule size (plasma proteins can’t) things in plasma can and becomes part of the filtrate d. Filtrate mirrors what is in plasma minus plasma proteins 3. Convoluted tubules, loop of Henle a. Proximal convoluted tubule b. Distal convoluted tubule c. Loop of Henle d. Collecting Duct = collects urine/filtrate from several nephrons Peritubular Capillaries

● Efferent arteriole breaks into 2nd capillary network, which surrounds renal tubule ● Allows exchange of materials b/w filtrate (renal tubule) and blood (in peritubular caps) ● Long loopy peritubular caps around loop of Henle are called “Vasa Recta” Blood Supply to Kidney ● 1 renal artery bringing blood in and 1 renal vein taking blood out Kidney physiology ● Kidneys filter 1000 - 1200 mL blood per minute ● About 125 mL becomes filtrate Basic Kidney Mechanism 1. Glomerular Filtration a. Blood under high pressure enters glomerulus, some of fluid and small solutes forced across filtration membrane - enters Bowman's capsule as filtrate b. Net Glomerular Filtration pressure = pressure out minus pressure in i. Blood pressure (out) = 55mm ii. Blood Osmotic (in) = 30 mm iii. Blood capsular (in) = 15 mm iv. Net = 10 mm c. Higher BP to push it out due to extra pressure going in d. Gives glomerular filtration rate (GFR) of about 125 mL/min i. Remains same despite changes in systolic pressure between 80-180 mm ii. B/C: 1. Afferent arteriole monitors BP, if BP increases or decreases, afferent arteriole will change diameter to maintain constant glomerular filtration pressure and GFR 2. Distal convoluted tubule monitors rate of filtrate flow thru tubule. If speed of filtrate flow increases or decreases, then distal convoluted tubule releases chemicals - changes diameter of afferent arteriole - maintain constant GFR 3. BUT GFR will decrease if: a. Systolic BP below 80 mm, JGA cannot compensate for BP that low b. Lots of sympathetic stimulation - decrease diameter of afferent arteriole massively - decrease blood in glomerulus 2. Tubular Reabsorption a. Nutrients, etc. removed from filtrate and returned to blood in peritubular cap. b. Requires carrier molecules (transport proteins) for nutrients c. Most nutrients are transported with salt (NaCl-) d. Tubular Maximum (™) = maximum amount of specific nutrient reabsorption per minute e. Depends on # of carrier molecules for the nutrient f. Most nutrients completely reabsorbed b/c ™ much greater than normal physiological levels i. Example: Blood Glucose 1. Tm = 320 mg/ 1000mL

2. Normal blood glucose 80-100 mg/ 1000 mL Diabetic 1. Glucose = 600 mg/ 1000 mL 2. Tm = 320, the other 280 mg/ 1000 mL - urine 3. Obligatory water reabsorption a. Where nutrients or solutes go --- water follows 4. Tubular Secretion a. Secreting waste, excess H, K from blood into filtrate b. Excess water, excess hydrogen (regulate blood pH), excess Na+, K+ c. Acidic transporters = remove acidic substances from blood --- to filtrate d. Basic transporters = take alkaline and puts it in filtrate 5. Water Reabsorption a. Take water out of filtrate and put it back into blood b. Descending loop of Henle is permeable to water but not salt (NaCl-) c. Ascending loop of Henle actively pumps salt out, impermeable to water d. Water goes out of descending limb and goes into peritubular capillary e. As filtrate descends loop of Henle it enters very salty environment -- water leaves filtrate and enters peritubular cap (b/c cap has same salt concentration as filtrate in tubule) f. Filtrate becomes more concentrated inside tubule as water leaves g. As filtrate goes up Ascending limb -- salt is pumped out -- when it reaches top, filtrate is more dilute because so much salt is pumped out h. Salt that is pumped out of filtrate enters peritubular caps i. Collecting duct passes thru medulla with high salt concentration i. Water can be reabsorbed from collecting duct (enters blood in peritubular cap) but volume of water reabsorbed varies with levels of certain hormones: 1. Facultative water reabsorption: cause urine levels to decrease a. Antidiuretic hormone (ADH) i. Causes production of more water channels in collecting duct -- water leaves filtrate and goes into peritubular capillary b. Aldosterone i. Causes the production of sodium pumps in collecting ducts -- sodium is pumped out of filtrate -Cl- and water follow and enter the peritubular capillary Ureters ● Composed of: ○ CT, smooth muscle, mucous membrane (transitional epith) ● Kidney to urinary bladder ● Urine more thru by peristalsis ● Enters underside of bladder, b/c have no sphincter so weight of bladder will close openings ii.

Urinary Bladder ● Composed of: ○ CT, smooth muscle, mucous membrane (transitional epith) ○ Detrusor muscle = temporary storage for urine Urethra ● Urinary bladder to external body ● Composed of: ○ CT and mucous membrane ● Males urethra: ○ 3 parts ■ Prostatic urethra = thru prostate gland (3 cm) ■ Membranous urethra = thru pelvic floor (1cm) ■ Penile (spongy) urethra = varies b/w people ○ 2 sphincters ■ Internal urethral sphincter ● Smooth muscle, base of bladder ■ External urethral sphincter ● Skeletal muscle, in pelvic floor ■ These two are separated by the prostatic gland ● Female Urethra ○ 4 cm long, anterior to vagina ○ External urethral sphincter = skeletal muscle ○ Internal urethral sphincter = smooth muscle Urination (Micturition reflex) ● 200 - 400 mL of urine in bladder ● Stimulates stretch receptors in bladder ● Info sent to spinal cord: ○ Reflexive response = cx detrusor muscle in bladder and relax internal urethral sphincter ○ Info to cerebral cortex = conscious awareness, vol control of exit, urethral sphincter Acidosis and Alkalosis ● pH = measure of H+ (acid) in solution ○ Neutral = 7 ○ pH in blood ■ Normal 7.35 - 7.45 ■ Acidosis = below 7.35 ■ Alkalosis = above 7.45 ● Maintaining normal pH ○ Respiratory system ■ Changes in CO2 levels due to ventilation ■ Change ventilation = changes CO2 levels = changes pH ○ Urinary (renal) system ■ Secretion of reabsorption of:

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H+ = acid HCO3- = base

The Female Reproductive System Organs of Female Reproduction ● 2 ovaries = produce eggs and hormones estrogen and progesterone ● 2 fallopian tubes = site of fertilization (outer ⅔ of tube) and move egg to uterus using cilia and peristalsis ● 1 uterus = retains and nourishes the embryo, has smooth muscle: cx to push fetus out in childbirth ● 1 vagina = receives semen, passageway for menstrual fluid and baby ● External genitals = vulva ● Mammary glands = breast Ovaries ● Almond shaped, 2x size of a almond tho ● Tunica albuginea = white CT around ovary ● Attaches to lateral walls of uterus by ovarian ligament ● Born with all eggs (100,000 to 2 million) ○ Eggs = oocytes that develop in “follicles” (egg + surrounding cells called “granulosa cells”) ● It takes several menstrual cycles to get follicle from one stage to the next and a majority do not survive to the last cycle Fallopian (uterine) Tube ● Isthmus = narrow region where tube joins uterus ● Ampulla = wider area ● Infundibulum = funnel shaped region at end of tube ○ Finger-like extensions of infundibulum called “Fimbriae” ● The tube does not directly attach to the ovary ● Fimbriae to ovulation make sweeping motions to draw egg into tube Clinical importance of tube and ovary not in direct contact: 1. Infection - pelvic inflammatory disease a. Opening into pelvic cavity i. Pelvic inflammatory inflammatory disease = infection extends beyond vagina ii. Causes swelling and scar tissue development (block tube) iii. Adhesions: 1. Internal scar tissue that abnormally joins organs 2. Overtime scar tissue shrinks and kinks tube and sperm cannot get thru 3. Chlamydia = # 1 cause of infertility in women 2. Ectopic Pregnancy a. Pregnancy that implants outside normal place in uterus b. 90% are “tubal pregnancy” due to scar tissue because sperm gets thru but egg is

too big c. Fetus never finishes development b/c tube rupture Tubal ligation ● Cutting and tying the tubes to prevent sperm from reaching egg ● Ovaries still work and make hormones ● Still have menstrual cycle Uterus ● Cervix = the neck of the uterus, extends into vaginal orifice ● Vaginal fornix = space b/w cervix and wall of vagina “blind end pockets” ○ Posterior oen is great place for infections to hide ● Cervical os (mouth) ● Cervical canal ● Uterus cavity ● Fundus = upper rounded region ● Body ● “cervical glands” secrete mucus into cervical canal ○ Very thick to keep microbes out ○ Just before ovulation due to increase in estrogen levels, changes mucus to thin and stringy to allow and help sperm up into uterine cavity Uterine Wall ● 3 layers of tissue: ○ Perimetrium = outer layer, serous membrane (visceral peritoneum) ○ Myometrium (middle) = smooth muscle, cx during labor, thickest layer ○ Endometrium (inner) = mucous membrane ■ 2 layers: ● Stratum functionalis = deepest layer, closest to uterine cavity gts thick and spondy to prepare for pregnancy ○ Has spiral arteries and uterine glands (secrete glycogen) ○ Embryo implants in it ○ If NO pregnancy = entire layers it lost in menstrual fluid ● Stratum Basale = next to myometrium and doesn’t undergo changes in response to hormones Ligament and muscular support to the female reproductive organs: 1. Broad ligament a. Serous membrane that draps/folds over reproductive organs and attaches to lateral walls of pelvis (bone) b. Primary Support c. 2 pocket-like areas as the broad ligament folds over organs i. Vesicouterine pouch = b/w uterus and bladder ii. Rectouterine pouch = b/w uterus and rectum 2. Round ligament a. Attaches to the side of the uterus, just below the fallopian tubes b. Travels anterior to the pubic bone c. Attaches to subcutaneous tissue of labia majora (external genitals)

3. Uterine positions a. Anteverted (anteflexed) Uterus = forward tilt of uterus b. Retroverted (retroflexed) uterus = posterior tilt of uterus 4. Uterosacral ligaments a. Go from uterus to sacrum 5. Ovarian ligaments a. Go from lateral wall of uterus to ovaries 6. Skeletal muscles of pelvic floor a. Primary inferior support that form a sling of muscles 7. Prolapsed Uterus a. When uterus slips down out of normal position, often in older individuals due to decrease muscle and multiple births stretched out ligaments Vagina (Birth Canal) ● Smooth muscle, CT, mucous membrane (folds = “rugae”) which allows for stretching ● Vaginal orifice = external opening ○ Has openings to vestibular glands which secrete mucus to keep external genitals moist ■ Increases secretion during sexual arousal for lubrication ● Hyman ○ Mucous membrane which may partially cover vaginal orifice of people who have not had sex External Genitals (Vulva) 1. Mons pubis a. Fatty pad over pubic bone b. Extending posteriorly from mons pubis, 2 skin folds: i. Labia Majora = lateral pair of skin folds; larger, more fat and glands, after puberty = pubic hair ii. Labia Minora = medial pair of skin folds; less fat, fewer glands, and no pubic hair iii. Vestibule = area b/w Labia minora 1. Vaginal orifice = openings to vestibular glands 2. External urethral orifice = openings to paraurethral glands a. Secrete mucus to keep things moist and increases during arousal Clitoris ● Anterior to vestibule ● Homologous to penis ● Made of erectile tissue (fills with blood - enlarges and more firm) ● Partially covered by foreskin (prepuce) ● attaches to pubic bone by “Crura” ● Lots of sensory neurons Female sexual response ● Sexual arousal regulated by parasympathetic NS (feeding and breeding system) ● Increase mucus secretion by paraurethral and vestibular glands

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Erectile tissue in clitoris, vaginal mucosa and nipples fill with blood When parasympathetic stimulation reaches critical point = orgasm = triggers sympathetic and somatic responses ○ Symp response = cx uterine and vaginal smooth muscle ○ Somatic response = cx bulbospongiosus muscle in pelvic floor Menstrual Cycle ● Cyclic hormonal interaction b/w pituitary gland (FSH & LH) and ovaries (estrogen & progesterone) ● Assume 28 day cycle = ovulation day 14 and day 1 is the first day of menstrual bleeding Pregnancy Hormones: ● HGC = produced mostly during first trimester ○ Responsible for morning sickness ○ Pee sticks use this hormone to test for pregnancy ● Placenta produces estrogen and progesterone (2nd and 3rd trimester) Menopause ● Cessation of menstrual cycles ● About 50 years of age ● Ovaries stop responding to FSH and LH ○ Causes no follicles ○ No estrogen ○ No ovulation ● After menopause: ○ Small amount of estrogen from adrenal glands

Male Reproductive System Reproductive Organs: ● 2 testes = produce sperm and the hormone testosterone ● Accessory glands = produce the fluid portion of semen (semen is fluids plus sperm) ● A duct system to transport semen to the exterior of the body Testes ● Location = scrotum ○ Because the temp in the abdominal cavity is too warm for normal sperm production ○ There is an ideal temp range for optimum sperm production - cooler than the body, but no too cool ● Descent of testes ○ The testes develop in the embryonic abdomen, descend into the scrotum in the 7th month of pregnancy through the inguinal canal (an opening in the abdominal cavity just anterior to the pubic bone ○ Failure of one or more testes to descend is “cryptorchidism” ● Surrounded by white CT covering called “tunica albuginea”

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Inside the testes are the seminiferous tubules where sperm are produced b/w the tubules are interstitial cells that produce testosterone So, sperm are produced in the tubules and testosterone is produced by cells between the tubules Blood supply to Testes ○ Testicular arteries ■ Branch directly from the aorta, travel thru the inguinal canal to reach the testes, carrying oxygenated blood ○ Testicular veins ■ Leave the testes and travel thru the inguinal canal into the abdominal cavity and join with the inferior vena cava. Transports testosterone from testes to rest of body ○ Pampiniform plexus (veins) ■ A network of veins that unites to form each testicular vein ■ These surround the testicular artery, which is bringing blood form the abdominal cavity ■ These absorb heat from the testicular artery, acting as a kind of “heat exchanger”

Scrotum ● Is composed of skin, smooth muscle known as the “Dartos Muscle” and CT ● Temperature regulation in testes ○ Muscles which can move the testes closer to, or further from the body to control temp for optimem sperm production ■ Dartos Muscle = in the scrotum, contraction of the muscle causes wrinkling of the scrotum, drawing testes closer to body, making them warmer ■ Cremaster muscles = are extensions of the internal oblique abdominal muscle, passes thru the inguinal canal, attaches to testes. Cx pulls the testes closer to the body, making them warmer Spermatic cord ● All structures which pass between abdominal cavity and scrotum (testicular artery and vein, vas deferens, cremaster muscles, lymphatic vessels, nerves) are bundled together and enclosed in CT ○ Entire bundle is called “spermatic cord” that passes thru the inguinal canal Spermatogenesis (sperm formation) ● Begins development at outer wall of seminiferous tubules, and as they mature, they move into center (lumen) of the tubule A. Spermatogonia = have 46 chromosomes. At the outer wall of the seminiferous tubule a. These cells divide by mitosis to produce 2 cells, one of which remains at the outer wall of the tubule and the other becomes a primary spermatocyte i. The primary spermatocyte divides by meiosis to produce 4

spermatids, each of which has 23 chromosomes As spermatids mature, they move toward the center of the seminiferous tubule, lose much of their cytoplasm and produce flagellum = then are sperm B. Fully formed sperm have 3 parts: a. Head = contains the nucleus (with DNA, 23 chromosomes) and the “acrosome” which has enzymes to digest the material around the egg so that fertilization can occur b. Midpiece = lots of mitochondria, which produces ATP for the sperm’s long journey thru the female reproductive system c. Flagellum or tail = for swimming, sperm complete their development here, but are not yet mature, cannot swim C. Sustentacular cells = large, columnar shaped cells which extend from wall of seminiferous tubule to lumen - completely surround the developing sperm a. Functions of cells: i. Surround, protect, and nourish the developing sperm ii. Form the blood testes barrier, which protects the sperm from immune system attack (since sperm have only 23 chromosomes, which are not identical to the rest of the body cells, the immune system would see them as “foreign”) iii. Produces a fluid to move sperm out of the tubule because they cannot swim yet iv. Produce androgen binding protein, which keeps some testosterone in the seminiferous tubules, since it is needed for normal sperm production Duct system = transports semen to the exterior of body 1. Epididymis = comma shaped structures on the...