Anatomy Exam 4

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Identify and describe the collecting tubules, collecting ducts, and papillary ducts.

-DCT connects to collecting tubules which drain into the larger collecting duct -Passes through the center of a renal pyramid -Collecting ducts make final changes to the concentration of the filtrate -Collecting ducts merge into the papillary ducts which empty into minor calyxes. -No further adjustment to filtrate = URINE

Describe the pathway of sperm from the seminiferous tubules to the external urethral orifice of the penis.

1. Seminiferous Tubule 2. Rete Testis -> Efferent Ductules 3. Head, Body, Tail of Epididymis 4. Ductus Deferens 5. Ejaculatory Duct 6. Prostatic -> Membranous -> Spongy Urethra Parasympathetic Activation •Erection •Smooth muscles in the arterial walls relax •Arterial vessels dilate •Arterial vessels and vascular channels within the corpora cavernosa and corpus spongiosum become engorged with blood Sympathetic Activation •Emission •Sperm mixed with semen by peristaltic actions of smooth muscle in the: •Ductus deferens •Seminal glands •Prostate •Bulbo-urethral glands •Ejaculation—powerful contractions of ischiocavernosus and bulbospongiosus push semen toward external urethral orifice Semen •Transit time from seminiferous tubules to ejaculate •about two weeks

1. Identify the specific segments and related flexures of the large intestine. a. Know which segments are retroperitoneal and which are intraperitoneal

CECUM •Blind sac 1st portion of large intestine •In RLQ •Chyme exits ileum through ileocecal valve into cecum •Vermiform appendix projects inferiorly from the cecum APPENDIX •Thin hollow sac lined with lymphatic nodules •Appendix may harbor beneficial bacteria that help colon function THE COLON •Begins at ileocecal valve and ascends superiorly in RLQ •As it approaches inferior surface of liver, colon bends at right colic flexture and extends horizontally to the left as the transverse colon •Near spleen, colon bends inferiorly at left colic flexure •Descends inferiorly on left side of abdomen as •Bends again at sigmoid flexure & continues medially as sigmoid colon RECTUM •Muscular tube that expands to store feces prior to defecation •Final few cm of rectum = anal canal •stratified squamous epithelium •Anal columns & anal sinuses - pressure of fecal matter passing causes mucus secretion from anal sinuses •Involuntary internal anal sphincter •Voluntary external anal sphincter •Generally closed, but must relax for defecation a. Both cecum & appendix are intraperitoneal •Ascending colon is retroperitoneal •Transverse colon is intraperitoneal Descending colon (retroperitoneal) •Sigmoid is intraperitoneal & terminates at rectum (Retroperitoneal)

Compare and contrast the anatomy of the male urethra versus the female urethra. Compare and contrast the locations, innervation and functions of the internal urethral sphincter and external urethral sphincter.

Female Urethra single function: to transport urine from urinary bladder to exterior lumen lined with stratified squamous epithelia at external urethral orifice in female perineum Male urethra •passageway for urine and semen •three segments: prostatic urethra, membranous urethra, spongy urethra •prostatic urethra •extends through prostate gland inferior to male bladder •most dilatable portion •lined by transitional epithelium •membranous urethra •shortest and least dilatable portion •from inferior prostate gland through urogenital diaphragm •surrounded by muscle fibers forming external urethral sphincter •spongy urethra •longest part of male urethra •encased in cylinder of erectile tissue in penis, corpus spongiosum •extends to external urethral orifice •Histology along these segments progresses from psuedostratifed columnar > stratified columnar > stratified squamous epithelium

1. Trace the flow of filtrate through the kidney beginning at the renal corpuscle. a. Understand the layers of the filtration membrane and what substances are filtered from the blood vs. what remains in the blood.

Filtration membrane characteristics: •Porous, thin, negatively charged structure (positively charged ions easily enter) •Formed by glomerulus and visceral layer of glomerular capsule •Composed of three sandwiched layers •to enter filtrate, substance must pass through 5 parts of filtration barrier Filtration Barriers 1. Endothelium surface layer of glomerulus •innermost layer (closest to lumen) •fenestrated, allowing plasma and dissolved substances to be filtered •restricts passage of large structures (e.g., erythrocytes) 2. Glomerular capillary endothelium 3. Basement membrane of glomerulus •porous middle layer •composed of glycoprotein and proteoglycan molecules •restricts passage of large plasma proteins 4. Visceral layer of glomerular epithelium •composed of specialized cells, podocytes •have long secondary processes •wrap around glomerular capillaries •support capillary wall but don't completely ensheathe it •separated by thin filtration slits •restrict passage of most small proteins 5. Subpodocyte space Filtrate includes water, glucose, amino acids, ions, urea, many hormones, vitamins B and C, ketones, and very small amounts of protein Not Filtered Platelets Erythrocytes Leukocyte Large Proteins

Explain the differences between the gastrointestinal (GI) tract and the accessory digestive organs.

GI TRACT - Oral Cavity - Pharynx - Esophagus - Stomach - Small Intestine - Large Intestine - Anus ACCESSORY DIGESTIVE ORGANS -Teeth -Tongue -Salivary Glands -Liver -Gallbladder -Pancreas

Identify male and female homologues of various reproductive system structures (e.g., ovary is homologous to the testis).

Homologues in reproductive system •Structures derived from common developmental structures •Serve similar function in adults Primary reproductive organs = gonads •Ovaries in females; testes in males •Produce sex cells, gametes •unite at fertilization to initiate formation of new individual •occurs during copulation (coitus) Produce large amounts of sex hormones •affect maturation, development, activity of reproductive organs Accessory reproductive organs •e.g., ducts to carry gametes away from gonads •toward site of fertilization (females) •toward outside of body (males)

Describe the major functions of the digestive system.

INGESTION •1st step in the process of digesting & absorbing nutrients •Introduces solid/liquids into the oral cavity MOTILITY •Voluntary and involuntary muscular contractions •Mix & move materials through the gastrointestinal tract SECRETION •Production & release of digestive enzymes, acid & bile that facilitate digestion DIGESTION •Mechanical digestion •Chemical digestion ABSORPTION •Passive movement & active transport of substances from GI tract into blood or lymph ELIMINATION •Expulsion of indigestible & unabsorbed components

1. Explain the difference between an intraperitoneal and a retroperitoneal organ. 2. Identify which digestive system organs are intraperitoneal or retroperitoneal.

Intraperitoneal: Completely surrounded by the visceral peritoneum •Stomach, most of small intestine, parts of large intestine Retroperitoneal: Lie directly against the posterior abdominal wall, only anterolateral surfaces covered by peritoneum •Duodenum, pancreas, ascending & descending colon, rectum

1. Describe the major functions of the urinary system. a. Compare and contrast the functions of the kidney with the functions of the urinary tract (ureters, urinary bladder and urethra)

Kidneys •remove waste products from blood and converts filtrate into urine •Formation of calcitriol •Makes final enzyme in calcitriol ( Vitamin D) hormone formation •Increases absorption of calcium from small intestine •Production and release of erythropoietin •indirectly measures oxygen level of blood •secretes erythropoietin (EPO) in response to low blood oxygen •stimulates red bone marrow to increase rate of erythrocyte formation •erythrocytes transport additional oxygen from lungs •Regulation of ion levels and acid-base balance •helps control blood's inorganic ion balance •e.g., Na+, K+, Ca2+ •aids in maintaining acid-base balance (pH) of blood •alters levels of H+ and HCO3- •Regulation of blood pressure •alters amount of fluid lost in urine which helps regulate blood volume •releases renin enzyme which is required for production of angiotensin II (increases blood pressure) •Potential to engage in gluconeogenesis •during prolonged fasting or starvation, kidneys produce glucose from noncarbohydrate sources to help maintain normal blood glucose levels *** In general - the kidneys take care of your blood. Healthy kidneys à healthy blood*** Ureters • transport urine from kidneys to urinary bladder Bladder •expandable muscular sac •stores as much as 1 L urine Urethra •eliminates urine from body

Identify the small intestine and describe its location relative to other body structures.

LOWER GI TRACT •Duodenum, jejunum, ileum •*remember duodenum is UPPER GI •Receives chyme from stomach •Responsible for most of the chemical digestion Most absorption occurs here

1. Describe the specializations of the stomach's tunics compared to the tunics of the rest of the GI tract. a. Relate the specializations of the stomach's tunics (e.g., number of layers of muscle in the muscularis) to the organ's functions. b. Identify and describe the gastric glands, including parietal and chief cells

MUCOSA •Thin - only ~1.5mm at thickest point •3 Significant Features of Stomach Mucosa •Simple columnar epithelium supported by lamina propria •Indented by numerous depressions called gastric pits •Gastric glands extend deep into mucosa from gastric pits •Muscularis mucosae contracts around gastric glands to expel their secretions SUBMUCOSA -Houses arteries, veins, and submucosal nerve plexus MUSCULARIS •Has 3 smooth muscle layers instead of 2 (like rest of GI tract) •Inner oblique layer •Middle circular layer • Outer longitudinal layer •3rd layer assists with churning & blending to mechanically digest bolus •Oblique layer is most developed in the cardia and body regions •Muscularis gets thicker from the body to the pylorus SEROSA b. Surface Mucous Cell - Lines stomach and gastric pit Mucous Neck Cell - At base of gastric pit, secretes acidic mucin Parietal Cells - Secretes intrinsic factor, H ion, and Cl ion Chief Cells - Most numerous cells of gastric gland, secretes Pepsinogen (protein breakdown) & gastric lipase (fat digestion) G- Cells - Enteroendocrine cells, secrete gastrin that stimulates stomach secretions and motility

Define mechanical digestion and chemical digestion. a. Compare and contrast where mechanical digestion and chemical digestion occur in the digestive system.

Mechanical Digestion: The physical breakdown of ingested material by chewing & mixing (No change to chemical structure) -Teeth/Mouth Chemical Digestion: specific enzymes break chemical bonds (Changes large complex molecules into smaller molecules for absorption) -Enzymes/Stomach UPPER GI TRACT- both mechanical and chemical digestion takes place

1. Describe the specializations of the large intestine's tunics (e.g., composition of the muscularis) compared to the tunics of the rest of the GI tract. a. Relate the specializations of the large intestine's tunics (e.g., composition of the muscularis) to the organ's functions.

Mucosa •Simple columnar epithelium + Goblet cells •smooth in contrast to small intestine •No villi •Openings lead internally to the intestinal glands •These secrete mucus to lubricate passage of feces through colon •Lots of lymphatic nodules in the lamina propria of the mucosa Muscularis is 2 layers •Inner circular is continuous •Outer longitudinal is discontinuous & forms the teniae coli

Describe the specializations of the esophageal tunics (e.g., composition of the mucosa and muscularis) compared to the tunics of the rest of the GI tract. a. Relate the anatomical specializations of the esophagus to the organ's functions.

Mucosa = nonkeratinized stratified squamous epithelium •Does NOT absorb nutrients Submucosa = thick with elastic fibers to allow distention of esophagus •Houses mucous glands that provide lubricating mucus •Ducts of these glands open into lumen of esophagus Muscularis = Blend of both smooth & skeletal muscle (unique) •2 muscle layers in superior 1/3 of esophagus are skeletal •Gets swallowed food out of pharynx rapidly before next inspiration •In middle 1/3 of esophagus smooth & skeletal muscle intermingle Inferior 1/3 = smooth muscle

1. Identify and describe the structure of a typical nephron, including the renal corpuscle [i.e., glomerular (Bowman's) capsule and glomerulus], renal tubule [i.e., proximal convoluted tubule, nephron loop (loop of Henle), distal convoluted tubule]. a. Compare and contrast cortical nephrons and juxtamedullary nephrons.

Nephron: •Microscopic functional filtration unit of kidney •Consists of renal corpuscle and renal tubule •All of corpuscle and most of tubules reside in cortex Renal corpuscle: •Enlarged bulbous region of nephron within renal cortex •Vascular pole- afferent and efferent arterioles attaching to glomerulus •Tubular pole- where renal tubule originates •Composed of glomerulus and glomerular capsule Glomerulus: •tangle of capillary loops - glomerular capillaries •blood entering by afferent arteriole •exits by efferent arteriole Glomerular Capsule: •internal permeable visceral layer overlying glomerular capillaries •external impermeable parietal layer of simple squamous epithelium capsular space between two layers receives filtrate, modified to form urine Renal Tubule: •Reabsorbs useful organic material and ions & >99% of water from the tubular fluid •Secretes waste products into tubular fluid •Made of three continuous parts •proximal convoluted tubule (PCT) •Water, ions, organic nutrients reabsorbed •nephron loop •Descending - water out of fluid •Ascending - Na+, Cl- out of fluid •distal convoluted tubule (DCT) •Further adjusts water and ions under control of hormones Cortical nephrons •have short nephron loop just penetrating medulla •mostly within cortex •85% of nephrons Juxtamedullary nephrons •renal corpuscles adjacent to corticomedullary junction •long nephron loops extending deep into medulla •help establish salt concentration gradient in interstitial space •allow for regulation of urine concentration

1. Define the process of oogenesis (oocyte development) 2. Describe the stages of folliculogenesis (ovarian follicle development) during a typical ovarian cycle

Oogenesis: production of female gametes •Oogonia > primary oocytes > secondary oocytes •Ovarian Cycle: Maturation of support cells (follicles) •Both processes occur simultaneously •six ovarian follicle types at different stages of development are found in cortex 1. Primordial follicle •most primitive type •primary oocyte + single flattened layer of follicle cells •primary oocyte arrested in prophase I of meiosis •1.5 million present at birth •Dormant until puberty •FSH initiates Ovarian Cycle 2. Primary follicle forms from maturing primordial follicle •primary oocyte + layers of cuboidal granulosa cells •secretes estrogen •stimulates changes in uterine lining •Zona pellucida - glycoprotein coated region between granulosa cells & primary oocyte •thecal cells on periphery of follicle •help control follicle development •secrete androgens converted to estrogen by granulosa cells 3. Secondary follicle forms from primary follicle •primary oocyte + many layers granulosa cells Vesicular Follicle (Tertiary/ Graafian) •contain fluid filled space = antrum •serous fluid increases as ovulation nears •Secondary oocyte forced to one side of follicle •has completed meiosis I •arrested in metaphase II •zona pellucida •contains glycoproteins •corona radiata • innermost layer of cumulus oophorus cells •Surround secondary oocyte •one formed per month 5. Corpus luteum formed from remnants of vesicular follicle •after rupture and oocyte expulsion •secretes progesterone •stimulate buildup of uterine lining •prepare uterus for possible implantation of blastocyst 6. Corpus albicans formed from regressed corpus luteum •~12 days post ovulation if pregnancy does not occur •white connective tissue scar •most structures completely resorbed •Marks end of ovarian cycle Oogenesis •Prior to birth •Oogonium > primary oocyte > paused in meiosis I •Puberty •Meiosis I completes > Secondary oocyte > paused in meiosis II •Fertilization •Meiosis II completes > mature oocyte

List and identify the organs that compose the GI tract.

Oral Cavity Pharynx Esophagus Stomach Small and Large Intestine Anus

Contents of upper GI tract

Oral Cavity & Salivary Glands •Mastication •Saliva is secreted in response to food in the oral cavity •Saliva + chewed food = bolus Pharynx •Swallowing of bolus •Mucus in saliva and in superior part of esophagus facilitates swallowing Esophagus •Transports bolus to stomach •Mucus in esophagus lubricates for passage of bolus Stomach •Smooth muscle in stomach mixes bolus with gastric secretions (HCl, digestive enzymes, mucin) •Once mixed, acidic puree is formed called chyme *Upper GI also includes the first part of the small intestine - the duodenum

Describe the location of the major salivary glands (i.e., parotid, submandibular, and sublingual) and their respective ducts.

PAROTID GLANDS •Largest salivary glands •Located anterior & inferior to ears, partially overlying masseter •Produce 25-30% of the saliva; only serous secretions •Saliva travels through parotid duct to the vestibule of the oral cavity (near 2nd upper molar) SUBMANDIBULAR GLAND •Inferior to floor of oral cavity & medial to body of mandible •Produce 60-70% of saliva; serous & mucous secretion •Submandibular duct moves saliva from glands through a papilla in floor of oral cavity on either side of the lingual frenulum SUBLINGUAL GLAND •Inferior to the tongue, medial & anterior to the submandibular salivary glands •Multiple tiny sublingual ducts extend from each gland to inferior surface of the oral cavity •Only make ~3-5% of the saliva; serous and mucous secretion

Define peristalsis and segmentation

Peristalsis: Alternating contraction of inner & outer muscles to propel materials Segmentation: Back & forth kneading motion by the circular inner layer of muscle. Lacks a directional movement. Blends ingested materials with GI tract secretions

1. Identify and describe the gross anatomy, microscopic anatomy and functions of the female reproductive system structures, including the: a. Ovaries. b. Uterine (fallopian) tubes. c. Uterus. d. Ligaments of the female reproductive system (including the broad ligament and its components, ovarian ligament, suspensory ligament of the ovary, and round ligament of the uterus). d. Vagina. e. External genitalia (including the mons pubis, labia majora, labia minora, clitoris, and greater vestibular glands). f. Mammary glands.

Primary reproductive organs •ovaries Accessory reproductive organs •uterine tubes, uterus, vagina, clitoris, external genitalia, mammary glands a. Ovaries •Site of oocyte production and sex hormone release •Paired, oval organs •Within pelvic cavity lateral to uterus •Slightly larger than an almond in an adult •Anchored by cords and sheets of connective tissue Mesovarium •double fold of peritoneum attaches to each ovary at hilum Broad ligament •drape of peritoneum hanging over uterus •attached to ovary via mesovarium Ovarian ligament •anchors ovary to posterior aspect of broad ligament •superior portion of round ligament of the uterus Suspensory ligament -attaches to lateral edge of each ovary -projects superolaterally to pelvic wall ovarian artery, vein, and nerves housed here Cortex Germinal epithelium •simple cuboidal epithelial layer surrounding ovary Tunica albuginea •deep to germinal epithelium •dense connective tissue capsule •Oocytes are made in cortex (outer region) Medulla •deep to cortex •areolar connective tissue •contains blood vessels, lymph vessels, nerves b. Uterine Tubes (Fallopian tubes) -Extend laterally from both sides of uterus toward ovaries -Covered and suspended by mesosalpinx -Infundibulum •free, funnel-shaped, lateral margin of tube •numerous fingerlike folds, fimbriae •enclose ovary only at the time of ovulation -Ampulla •expanded region of tube medial to infundibulum •fertilization typically occurs here -Isthmus •region of tube extending medially from ampulla -Uterine part of tube •extends medially from isthmus •penetrates wall of uterus c. Uterus •Pear-shaped muscular organ -Lumen •connects to uterine tubes superolaterally •connects to vagina inferiorly •Angled anterosuperiorly across superior bladder •anteverted •may shift to posterosuperior position in older woman •retroverted = projected toward rectum -Implantation site for blastocyst -Supports, protects, nourishes developing embryo •forms vascular connection that develops into placenta -Ejects fetus at birth -Contracts and sheds lining if oocyte not fertilized -Receives blood from uterine arteries (branches of internal iliac) -Fundus •broad superior region between attachments of uterine tubes -Body •middle region, major part of the organ •composed of thick wall of smooth muscle -Isthmus •narrow constricted inferior region •superior to cervix -Cervix •narrow inferiormost part of uterus •projects into the vagina •Internal os •superior opening of cervical canal •Cervical canal •narrow channel within cervix •connects to vagina •External os •inferior opening of cervix into vagina •covered by nonkeratinized stratified squamous epithelium Support •Muscles of pelvic floor •pelvic diaphragm and urogenital diaphragm •hold uterus and vagina in place •help resist intra-abdominal pressure on pelvis Round ligaments •extend from lateral uterus and traverse inguinal canal •attach to labia majora Layers •Perimetrium •outer serosa, continuous with broad ligament •Myometrium •thick middle tunic of three layers of smooth muscle •Endometrium •Internal glandular epithelium •simple columnar epithelium and underlying lamina propria •compound tubular glands, uterine glands •more superficial functional layer beginning at puberty •grows from basal layer under influence of estrogen and progesterone •sheds during period d. Vagina •Thick-walled fibromuscular tube •Forms inferiormost region of female reproductive tract •Connects uterus with outside of body •Functions as birth canal •Receives penis during intercourse •Passageway for menstruation Mucosa •nonkeratinized stratified squamous epithelium •highly vascularized lamina propria •produces acidic secretion helping to prevent infection Muscularis •has outer and inner layers of smooth muscle •Continuous with uterine myometrium e. External Genitalia •Vulva (entire region of external genitalia) •Mons pubis •expanse of skin and subcutaneous tissue •immediately anterior to pubic symphysis •covered in pubic hair in postpubescent females •Labia major •paired thickened folds of skin and connective tissue •homologous to scrotum in male •covered with pubic hair in adulthood •contain numerous sweat and sebaceous glands •Labia minora •paired folds internal to labia major •highly vascular areolar connective tissue •devoid of hair •sebaceous glands and melanocytes •Vestibule •Area surrounded by labia minora •Vaginal entrance •Vestibular glands •Homologous to male bulbourethral gland •Secrete lubricating mucus •Clitoris •small erectile body in anterior region of labia minora •homologous to penis •has many specialized sensory nerve receptors for pleasure •has body, corpora cavernosa, crus, glans •Covered by prepuce f. Mammary Glands •Located within anterior thoracic wall in pectoral fat pads •Composed of tubuloalveolar exocrine mammary glands •Secretory product, breast milk •contains proteins, fats, lactose sugar for infant nutrition Nipple •contains multiple tiny openings of the excretory ducts •transport breast milk Areola •pigmented ring around the nipple •uneven surface due to sebaceous glands, areolar glands •often darker in woman who has given birth (parous) •lighter in woman who hasn't (nulliparous) Suspensory ligaments •fibrous connective bands supporting breast •extend from skin & attach to deep fascia overlying pectoralis major •Subdivided into lobes •Further subdivided into lobules •contain secretory units, alveoli •produce milk in lactating female •become more numerous and larger during pregnancy •drained by tiny ducts •Lactiferous ducts •larger channels of merged ducts, draining single lobe •expands to form lactiferous sinus, where milk stored Sympathetic: T10 Spinal segment Parasympathetic: Vagus nerve

1. Identify and describe the gross anatomy, microscopic anatomy, and functions of the male reproductive system structures, including the: a. Testes. b. Epididymis. c. Spermatic cord. d. Ducts [including ductus deferens, ejaculatory duct, and urethra]. e. Accessory glands [including seminal glands (seminal vesicles), prostate gland, and bulbourethral (Cowper's) glands]. f. External genitalia (including the scrotum and penis).

Primary reproductive organs •Testes Accessory reproductive organs •Ducts and tubules leading from testes to penis •Accessory glands Penis a. Testes •Relatively small organs housed within the scrotum •Produce sperm and androgens •Covered anteriorly and laterally by a serous membrane •tunica vaginalis •has outer parietal layer and inner visceral layer •separated by a cavity filled with serous fluid Tunica albuginea •thick fibrous capsule covering the testis •deep to visceral layer of tunica vaginalis Septa •internal projections of tunica albuginea •subdivide internal space into 250 lobules Mediastinum testis •thickening of tunica albuginea projecting into interior testis •contains blood vessels, ducts, lymph vessels, nerves Seminiferous tubules •extremely convoluted and elongated (~80cm long) •up to four per lobule •contain nondividing support cells, Nurse Cells (Sertoli cells) •help nourish developing sperm •release hormone inhibin when sperm count is high •inhibits FSH secretion and regulates sperm production •Maintain blood-testis barrier to prevent autoimmune destruction of sperm •contain dividing germ cells continuously producing sperm Interstitial spaces •spaces surrounding seminiferous tubules Interstitial Endocrine Cells (Leydig cells) •reside in interstitial spaces •stimulated to produce androgens by luteinizing hormone •most common = testosterone •vast majority released from interstitial cells •(small amounts secreted by adrenal cortex) b. Epididymis •Comma-shaped structure •Composed of internal duct and external covering of connective tissue •Head on superior testis surface •Body and tail on posterior surface of testis •Internally contains long duct of epididymis •4-5 meters long •lined with pseudostratified columnar epithelium with stereocilia •Stores sperm until fully mature •Sperm first entering epididymis: •look like mature sperm •can't move like mature sperm •if expelled too soon, not motile •if ejected too late = old sperm degenerate •~2 weeks to pass through epididymis c. Spermatic Cord •multilayered structure traveling from abdomen to testis •contains blood vessels and nerves supplying each testis •Smooth muscle = cremaster •Contraction raises scrotal sac closer to body •Testicular artery •branch from abdominal aorta •resides within spermatic cord •Pampiniform plexus •plexus of veins surrounding testicular artery •precools arterial blood prior to reaching testes d. Ducts Within Testis •Transport and store sperm as they mature Rete testis •interconnected channels in mediastinum testis •receive sperm from seminiferous tubules •lined by simple cuboidal epithelium •short microvilli covering luminal surface •merge to form efferent ductules Efferent ductules •connect rete testis to epididymis •lined with ciliated columnar epithelia •propel the sperm toward epididymis •nonciliated columnar epithelia •absorb excess fluid secreted by seminiferous tubules •drain into epididymis Ductus Deferens •Sperm enter ductus deferens after leaving epididymis •Thick-walled tube traveling •within spermatic cord through inguinal canal •within pelvic cavity, separating from other cord components •posteriorly along superolateral bladder •Enlarges and forms AMPULLA as approaches prostate •Unites with proximal seminal vesicle to form ejaculatory duct Ejaculatory Duct •Terminal portion of the reproductive duct system •pseudostratified ciliated columnar epithelium •Conducts sperm and component of seminal fluid toward the urethra •Opens into the prostatic urethra •Transports semen outside of the body Urethra e. Accessory Glands Seminal Glands •Elongated hollow organs on posterior urinary bladder lateral to ampulla of ductus deferens •Medial portion merges with ductus deferens to form ejaculatory duct •Secretes alkaline seminal fluid with fructose and prostaglandins •fructose provides nourishment to sperm •prostaglandins promotes widening of external os of cervix ~60% of semen volume Prostate Gland •Compact organ immediately inferior to bladder •20-30% of semen volume •Secretes prostatic fluid •rich in citric acid, •seminalplasmin, antibiotic combating urinary tract infection •PSA, enzyme to help liquefy semen following ejaculation Bulbourethral Glands (Cowper's) •Paired glands located within urogenital diaphragm •Each with short duct projecting into base of penis •enters spongy urethra •produce clear, viscous, alkaline mucus •protects urethra •serves as lubricant during intercourse f. External Genitalia Scrotum •Skin-covered sac between thighs •Provides a cooler environment •needed for sperm development and maturation •Homologous to labia majora in female •Contains ridgelike seam at midline, raphe •Scrotum wall = layer of smooth muscle (dartos) Contraction = wrinkling of scrotal surface Penis •Root •internally attached portion of penis •forms bulb and crus of penis •bulb attaching penis to bulbospongiosus muscle •crus attaching penis to pubic arch •Body •elongated portion made of erectile tissue •Glans •tip of penis •contains external urethral orifice •Prepuce (foreskin) •circular fold of skin •skin attached to raised edge of the glans •Three cylindrical erectile bodies within penis body •Paired corpora cavernosa •located dorsolateral •terminate in shaft of penis •Corpus spongiosum •ventral to them in midline •contains spongy urethra continuous within the glans

Define the processes of spermatogenesis and spermiogenesis

Spermatogenesis •process of sperm development •occurs within seminiferous tubule •begins during puberty with significant levels of FSH and LH Spermatogonia •diploid cells near base of seminiferous tubule •surrounded by cytoplasm •divide by mitosis into new spermatogonium and primary spermatocyte Primary spermatocyte •diploid undergo meiosis Secondary spermatocyte •produced by primary spermatocyte during meiosis I •haploid •relatively closer to seminiferous tubule lumen Spermatid •formed when secondary spermatocytes complete meiosis II •Haploid •near seminiferous tubule lumen Spermiogenesis •final stage of spermatogenesis •spermatid becoming mature spermatozoa = sperm •excess cytoplasm shed and nucleus elongates •acrosome cap, forms over nucleus •contains digestive enzymes to help penetrate secondary oocyte Describe the stages of spermatogenesis in the seminiferous tubule •tail formation from organized microtubules in cell •midpiece region containing mitochondria and centriole •stay in epididymis for period to become fully motile

1. Identify and describe the internal divisions of the renal tissue, including cortical and medullary structures. a. Distinguish histologically between the renal cortex and the renal medulla.

TISSUE LAYERS SUPPORTING KIDNEY: Innermost to Outermost Fibrous (renal) capsule •Dense irregular CT adhered to external surface of kidney •Maintains kidney's shape, protects from trauma & pathogen penetration Perinephric fat •adipose connective tissue external to fibrous capsule •provides cushioning and support for kidney Renal fascia •Dense irregular CT external to perinephric fat •Anchors kidney to surrounding structures Paranephric fat •outermost layer of adipose tissue surrounding kidney •provides cushioning and support for kidney

Identify the location, structures and cells of the juxtaglomerular apparatus and discuss its significance.

The Juxtaglomerular Apparatus •(JGA) Sits between distal convoluted tubule and vascular pole of renal corpuscle •Important structure in regulating blood filtrate formation •Macula densa cells (located in DCT) •Na+ sensor •Juxtaglomerular cells •Renin production •Extraglomerular mesangial cells (Sit in "V" of afferent and effernt arterioles) •Produces two hormones: •Renin: will increase blood pressure •Erythropoietin: involved in erythrocyte production

Be able to outline the steps of the urine storage reflex and the urine voiding reflex

The Urine Storage Reflex •1- Detrusor muscles relaxed •Allows bladder to expand •2- Internal urethral sphincter is contracted (sympathetic innervation, T11-L2) •3 - External urethral sphincter contracted (somatic innervation, S2-S4) Urine Voiding Reflex •1- 200-300 ml urine in bladder, baroreceptors activated by distended wall •2 - Baroreceptors signal through visceral sensory neurons to micturition reflex center in pons •3 - Micturition center signals through parasympathetic nerves along spinal cord to pelvic splanchnic nerves (S2-S4) •4 - This parasympathetic stimulation causes detrusor to contract, internal urethral sphincter to relax. •*At this point sensory axons relay need to urinate to cerebral cortex

Describe the compositions, locations and functions of the cardiac (inferior esophageal) sphincter and the pyloric sphincter.

The cardiac sphincter is a thin ring of smooth muscle that helps to prevent stomach contents from going back up into the esophagus. The pyloric sphincter is a ring of smooth muscle that connects the stomach and small intestine. It opens and closes to control the passage of partially digested food and stomach juices from the pylorus to the duodenum •Has 3 smooth muscle layers instead of 2 (like rest of GI tract) •Inner oblique layer •Middle circular layer • Outer longitudinal layer •3rd layer assists with churning & blending to mechanically digest bolus •Oblique layer is most developed in the cardia and body regions •Muscularis gets thicker from the body to the pylorus

Describe the composition and location of the ileocecal valve.

The ileocecal valve is a sphincter muscle situated at the junction of the ileum (last portion of your small intestine) and the colon (first portion of your large intestine). Its function is to allow digested food materials to pass from the small intestine into your large intestine

1. Identify and describe the gross anatomy and location of the ureters, urinary bladder, and urethra. 2. Identify and describe the microscopic anatomy of the ureters, urinary bladder, and urethra.

URETERS •Long endothelial-lined fibromuscular tubes •Conduct urine from kidneys to urinary bladder •Retroperitoneal •Originate from renal pelvis as it exits hilum of kidney •Enter posterolateral wall of base of urinary bladder •Called trigone area of bladder •compressed as bladder distends •decreases likelihood of urine backflowing while emptying MICRO •Wall composed of three tunics •Mucosa of transitional epithelium Impermeable to urine •Muscularis •Inner longitudinal & outer circular smooth muscle •Peristaltic contractions move urine through ureter •Adventitia URINARY BLADDER •Expandable, muscular container •Reservoir for urine •Positioned immediately posterior to pubic symphysis •Anteroinferior to uterus in females •Anterior to rectum and superior to prostate gland in males •Retroperitoneal •superior surface covered with parietal peritoneum •Inverted pyramidal shape when empty •oval shape when full Trigone: •posteroinferior triangular area of bladder wall •formed by imaginary lines connecting ureter openings and urethra •remains immobile as bladder fills and empties •funnel to direct urine into urethra during contraction of bladder wall MICRO Mucosa •innermost layer lining bladder lumen •formed by transitional epithelium •accommodates shape changes with distension •mucosal folds called rugae allow for greater distension Muscularis •three layers of smooth muscle •collectively termed detrusor muscle URETHRA •Epithelial-lined fibromuscular tube •Exits urinary bladder through urethral opening •Conducts urine to exterior of body Internal urethral sphincter: •involuntary, superior sphincter •composed of smooth muscle •surrounds the neck of the bladder •controlled by autonomic nervous system External urethral sphincter: •inferior to internal urethral sphincter •formed by skeletal muscle fibers of urogenital diaphragm •voluntary sphincter controlled by somatic nervous system •learn control of muscle during "toilet training"

1. With respect to the liver: a. Identify the general functions of the liver. b. Identify the liver and describe its location relative to other body structures. c. Identify and describe the individual lobes of the liver. d. Identify and describe the porta hepatis and the structures that enter and exit it. e. Describe the histological components of the classic hepatic lobule. Review the dual blood supply of the liver

a. Main function in digestion is to produce bile (emulsifier) b. Largest internal organ, RUQ immediately inferior to the diaphragm •All but the bare area is covered by a connective tissue capsule & a layer of visceral peritoneum. c. Right, left, quadrate (by gallbladder), caudate lobes d. Porta hepatis = crossbar of H •Site of blood vessels, lymph, nerve & bile duct enter/leave liver e. •Liver CT capsule extends into & divides it into 1000s of polyhedral hepatic lobules •the structural & functional unit of the liver •Each lobule is made of hepatocytes •At the periphery of each lobule is a portal triad •Hepatic duct bile ductule •Branches of hepatic portal vein •Branches of hepatic artery •Has central vein that drains each lobule •Central veins merge to form hepatic vein •Hepatic artery branches from the celiac trunk •Carries oxygenated blood •Hepatic portal vein carries deoxygenated blood from GI tract capillary beds •(~75% of blood in the liver is from the hepatic portal) •Blood from hepatic artery mixes in hepatic lobules with blood from hepatic portal vein and exchange of nutrient/gas occurs

1. With respect to the pancreas: a. Identify the general functions of the pancreas in digestion. b. Identify the pancreas and describe its location relative to other body structures. c. Identify the head, body and tail of the pancreas. d. Identify the major histological components of the pancreas (pancreatic acini and pancreatic islets [Islets of Langerhans]) and discuss their major functions.

a. Right behind stomach. Alpha cells produce glucagon (reigns insulin back into blood when too low) Beta cells produce insulin (Kicks glucose out of blood when too high) d. Acinar cells of pancreas make pancreatic juices: •Pancreatic amylase •Pancreatic lipase •Protein digesting proteases in inactive form •Nucleases digest DNA and RNA

1. With respect to the gallbladder: a. Identify the general functions of the gallbladder. b. Identify the gallbladder and describe its location relative to other body structures.

a. Stores, concentrates & releases bile that was produced by the liver •Bile is then released into the cystic duct on its way to the duodenum b. •Attached to inferior surface of the liver

1. With respect to the biliary apparatus: a. Identify the major functions of the biliary apparatus. b. Identify and describe the location of the biliary apparatus components: left and right hepatic ducts, common hepatic duct, cystic duct, common bile duct, main pancreatic duct, hepatopancreatic ampulla (ampulla of Vater), hepatopancreatic sphincter (sphincter of Oddi), major duodenal papilla. Trace the path of bile and pancreatic juice through through the biliary apparatus

a. To drain waste products from the liver into the duodenum. To help in digestion with the controlled release of bile. b. 1. Left and right hepatic ducts merge to form a common hepatic duct. 2. Common hepatic and cystic ducts merge to form a common bile duct 3. Main pancreatic duct merges with common bile duct at the hepatopancreatic ampulla, which extends into the duodenum. 4. Bile and pancreatic juices enter duodenum at the major duodenal papilla

Trace the path of blood flow through the kidney, from the descending abdominal aorta and renal artery to the renal vein and inferior vena cava

•20-25% of cardiac output (~1 L/ minute) Arteries •Blood delivered to each kidney by 1. Renal artery •arises from abdominal aorta 2. Segmental arteries 3. Interlobar arteries 4. Arcuate arteries 5. Cortical radiate arteries 6. Afferent arterioles NOW IN NEPHRON •After filtration occurs in the nephrons, blood leaves the kidneys via the: following vessels 7. Glomerular capillaries 8. Efferent arteriole 9. Peritubular capillaries and Vasa Recta OUT OF NEPHRON 10. Cortical radiate veins 11. Arcuate veins 12. Interlobar veins •There are no segmental veins 13. Renal vein

Identify and describe the boundaries of the oral cavity.

•Entrance to GI tract •2 distinct spatial regions •Vestibule / Buccal Cavity = space between the gums, lips & cheeks •Oral cavity = bounded laterally by cheeks, anteriorly by teeth, and leads to oropharynx posteriorly PALATE •Superior boundary of the oral cavity •Separates oral cavity from nasal cavity •Hard palate (anterior 2/3) •Palatine processes of maxilla + palatine bones •Prominent transverse palatine folds = rugae •Soft palate (posterior 1/3) & Uvula •elevate to close nasopharynx TONGUE -mixes & compresses food, helps swallowing & speech •Formed from skeletal muscle •Superior surface projections = papillae involved in taste •Lingual tonsils •Attaches to floor of oral cavity by lingual frenulum

Identify and describe the gross anatomic and microscopic structure and function of each of the GI tract tunics: mucosa, submucosa, muscularis (muscularis externa), and serosa or adventitia.

•From Esophagus through Large Intestine the GI tract is a hollow tube MUCOSA : Absorption •Mucous membrane •(1)Simple columnar epithelium (stomach, small & Large intestine) OR stratified squamous epithelium (esophagus) •(2) Lamina propria of areolar CT, small blood vessels, MALT, lymph vessels & nerves •Absorption occurs when substances move through epithelial cells and enter the blood/lymph capillaries found in the lamina propria •Muscularis mucosae - gently "shakes things up" •Thin layer of muscle deep to lamina propria •Contractions of this (1) facilitate secretion from mucosa to lumen & (2) increase contact between materials passing through lumen & the mucosa SUBMUCOSA •Mixture of areolar & dense irregular CT •Relative amount of each type of CT varies with the region of the GI Tract •MALT is found in this region •In the ileum, the lymphatic nodules are called Peyer patches (Appears different in differing regions of GI tract) •Has large blood vessels, lymph vessels & nerves •Houses the !!!!SUBMUCOSAL NERVE PLEXUS!!!! Fine branches of larger nerves + ganglia Innervate smooth muscle & glands of the mucosa & submucosa MUSCULARIS EXTERNA •Two layers of concentric smooth muscle •Inner layer is circumferentially arranged •Outer layer is longitudinally arranged •Between these two layers are axons & ganglia that control their contractions = !!!MYENTERIC NERVE PLEXUS!!! •Myenteric nerve plexus + Submucosal nerve plexus = !!!!enteric nervous system!!! •Inner circular muscle layer thickens to form sphincters (close the lumen in segments of GI tract to control movement into the next segment) •The muscularis mixes & propels contents within the GI tract •Contractions of circular layer constrict lumen Contractions of longitudinal layer shorten the tube •Together these contractions result in •Peristalsis and Segmentation SEROSA/ADVENTITIA •Depending on the location, the outer layer of the GI tract is an adventitia or a serosa •Adventitia - areolar CT; found on organs that reside outside the peritoneal cavity •Serosa - areolar CT, covered by visceral peritoneum and found on organs housed inside the peritoneal cavity

1. Identify the stomach and describe its location relative to other body structures. 2. List the general functions of the stomach.

•Holding sac found in the left upper quadrant of the abdomen •Inferior to the diaphragm •Continues mechanical and chemical digestion •Protein and fat begin to be chemically digested •3-4 L of food/drink enter stomach/day •Ingested nutrients spend 2-6 hours in the stomach •Stomach absorbs small, non-polar substances in contact with its mucosa (Alcohol and Aspirin)

1. List the general functions of the small intestine. 2. Identify the specific segments of the small intestine (i.e., duodenum, jejunum, and ileum), including their relative length.

•Long tube inferior to stomach •from pylorus of stomach to cecum of large intestine •Process ~9-10 L of food, water & digestive secretions/day •Ingested nutrients spend 9-12 hrs in small intestine •Absorbs most of nutrients including dietary vitamins •~6m long (20feet!) in the cadaver, shorter when alive DUODENUM •25 cm (10 inches) long; receives digestive enzymes from the pancreas, bile from the liver and gallbladder JEJUNUM •2.5 m (8 feet) long; most of the digestion and absorption occurs in the jejunum ILEUM •3.5 m (12 feet) long •Junction with large intestine •Ileocecal valve

Compare and contrast the major anatomy of the male and female reproductive systems.

•Means for sexual maturation •Production of special cells for procreation •Responsible for gametogenesis (formation of gametes) •Have obvious differences but share some general characteristics

Describe the composition and functions of saliva.

•Moistens food and helps form bolus •Consists of water, ions, buffers, and salivary amylase •Initiates chemical break down of starch (Salivary amylase) •Allows food molecules to dissolve to stimulate taste receptors •Cleanses oral cavity •Inhibits bacterial growth •Made by 3 pairs of salivary glands •Parotid •Sublingual •Submandibular

1. Describe the specializations of the small intestine's tunics [e.g., circular folds (plicae circulares), villi, and microvilli] compared to the tunics of the rest of the GI tract. a. Relate the specializations of the small intestine's tunics [e.g., circular folds (plicae circulares), villi and microvilli] to the organ's functions.

•Mucosa & Submucosal layer of small intestine are arranged as circular folds •Decrease in density as you progress from duodenum to ileum •Increase surface area for absorption & act as speed bumps to slow chyme down as it passes through •In addition to the circular folds, the mucosa layer is also folded into microscopic fingerlike projections called villi •muscularis mucosae is shorter in circumference than the epithelial and lamina propria layers internal to it. •Villi + Circular Folds = greatly increased surface area for absorption & secretion Each villus contains: •Arteriole •Rich capillary network for nutrient absorption •Venule •Lacteal (Lymphatic capillary receiving chyme) •Simple columnar epithelial cells of the villi also have microvilli on their apical surface •embedded with enzymes to complete chemical digestion = brush border enzymes

1. Identify and describe the gross anatomical regions of the stomach (i.e., cardia, fundus, body and pylorus).

•Muscular J-shaped organ •Large convex lateral surface = greater curvature •Smaller concave superomedial surface = lesser curvature 1- Cardia = small narrow superior entryway •Where cardia meets esophagus is the cardiac orifice 2 - Fundus = dome shaped region lateral and superior to cardia. •Contacts diaphragm with its superior surface 3- Body = largest region of stomach, inferior to cardiac orifice & fundus 4 - Pylorus = narrow medially directed funnel shaped pouch •Terminal region of stomach •Opens into duodenum at pyloric orifice, which is surrounded by the pyloric sphincter 5 - Gastric Folds = Only seen in an empty stomach •Allow great expansion of stomach when it fills with food & drink

1. Identify the esophagus and describe its location relative to other body structures. 2. List the general functions of the esophagus.

•Normally collapsed, muscular tube •~25 cm long (10 inches) in an adult •Begins at the level of the cricoid cartilage & continues into the thorax •Anterior to vertebral bodies until it passes through the esophageal hiatus of the diaphragm and connects to the stomach (Only ~1.5 cm is in the abdominal cavity) Superior esophageal sphincter: PREVENTS CHOKING •Ring of circular smooth muscle at superior end •Where esophagus & pharynx meet •Closed during inhalation Inferior esophageal sphincter: PREVENTS ACID REFLUX •Ring of circular smooth muscle at inferior end •With stronger diaphragm muscles helps prevent backflow of stomach contents (reflux) into the esophagus

Identify gastric folds (rugae) and discuss their functional significance..

•Only seen in an empty stomach •Allow great expansion of stomach when it fills with food & drink

Explain the gastrocolic and defecation reflexes relative to movement through the large intestine.

•Peristaltic movements = weak & sluggish, don't propel forward at rate in small intestine •Haustral churning = after haustrum fills, its distension stimulates contraction of the muscularis layer •Increases churning & propels material to next haustra Reflexes of Motility: The Gastrocolic Reflex •Initiated by distension of the stomach •Leads to a mass movement within the large colon •Mass movements = powerful contraction of the teniae coli •Move feces toward the rectum •Contraction wave begins in middle of transverse colon & moves material through descending & transverse colons & rectum •Occur 2-3x/day - usually after a meal Conscious control over defecation usually occurs after 3yrs of age Involves the Valsalva maneuver & relaxation of the external anal sphincter 1. Rectum contents stimulate baroreceptors in the rectal wall. 2. Sensory input initiated by baroreceptors in the rectum is relayed to the spinal cord 3. Motor output along parasympathetic axons is altered. 4. Increased motor output to smooth muscle of rectum; rectum contracts, squeezing the contents. Decreased motor output to internal anal sphincter causes sphincter relaxation 5. The conscious decision to defecate is controlled by the cerebral cortex. External anal sphincter relaxes and Valsalva maneuver is initiated, eliminating the feces

Identify and describe the functions of the teniae coli, haustra, and omental appendices (epiploic appendages).

•Teniae coli = thin longitudinal bundles of smooth muscle •Cinch the colon into sacs called haustra •Lobules of fat hang off of the exterior of the haustra = omental appendices

Identify and describe the external structure of the kidney, including its coverings, the renal hilum and renal sinus, and identify all structures included in the renal sinus

•Two symmetrical, bean-shaped organs •Concave medial border •Hilum: where vessels, nerves, ureter connect to kidney •Lateral border convex •Adrenal gland resting on superior aspect of kidney •Retroperitoneal, anterior surface covered by parietal peritoneum •Left kidney between level of T12 and L3 vertebrae •Right kidney inferior to left kidney to accommodate liver •Both only partially protected by rib cage •vulnerable to forceful blows to inferior region of back •Two regions of functional tissue (parenchyma) •Outer RENAL CORTEX and inner RENAL MEDULLA •RENAL COLUMNS •extension of cortex projecting into the medulla •Creates RENAL PYRAMIDS that have a striped appearance RENAL PYRAMIDS •8-15 pyramids in adult kidney •wide base at external edge of medulla, meeting cortex •termed corticomedullary junction •medial apex termed RENAL PAPILLA •RENAL LOBE components •renal pyramid and portions of adjacent renal columns •renal cortex external to base •RENAL SINUS •medially located urine drainage area •organized into minor calyces, major calyces, renal pelvis •MINOR CALYXES •funnel-shaped structures associated with renal pyramids •merge to form MAJOR CALYX •RENAL PELVIS •formed from merged major calyces •merges at medial edge of kidney with ureter •renal arteries, veins, lymph vessels, nerves, fat in space around pelvis

Review and understand the sympathetic, parasympathetic, and somatic innervation of the bladder and urethral sphincters.

•Urinary bladder •has sympathetic, parasympathetic, somatic innervation •Sympathetic axons •cause contraction of internal urethral sphincter •inhibits contraction of detrusor muscle and micturition •Urine Storage •Parasympathetic division •contraction of detrusor and relaxation of internal urethral sphincter •stimulates micturition •Urine Voiding •Pudendal nerve of somatic nervous system •innervates external urethral sphincter •contracts to prevent urination

Identify the large intestine, its general function, and describe its location relative to other body structures.

•Wider, significantly shorter than small intestine •Small intestine transfers ~1 L of digested material into the large intestine/day •The large intestine absorbs water and electrolytes •Primarily Na+ and Cl- ions •Only ~100ml of water is present in the feces as it is eliminated from the large intestine •Watery chyme enters large intestine & is solidified and compacted into feces •~ 6.5 cm in diameter •~1.5m (5ft) long •Origin is at ileocecal junction •Terminates at anus •3 major regions •Cecum •Colon Rectum


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