urinary system

• kidneys - Regulates the content of blood plasma to maintain homeostasis
• urinary system - excrete urine as waste
• kidneys - The principal organ of the urinary system which process blood and form urine as a waste to be excreted
• accessory organs: ureters, urinary bladder & urethra
• kidneys - it resemble lima beans
• both located in a retroperitoneal position
• o    Renal Fasciae – anchor the kidney surrounding structure
• o    Renal Fat Pad – heavy cusion of fat
• o    Hilum – concave notch on medial surface
• o    Cortex – outer region
• o    Medulla – inner region
• o    Renal Pyramids – comprise much of the medullary tissue
• o    Renal Columns – cortical tissue dips into the medulla
• o    Calyx – cuplike structure at each renal papilla to collect urine
• o    Renal Pelvi – narrows at it exits the kidney to become ureter
• o    Renal Artery – large branch of the abdominal aorta
• o    Interlobular Arteries – between the pyramids of medulla
• o    Afferent Arterioles – extends to the nephrons
• ureter - About 28 to 34 cm in length
• ureter - ®      Two tubes that actively convey urine
• ureter -®      Open at lateral angles of trigone (floor) of the bladder
• ureter - ®      End of tube close, preventing backflows of urine
• ureter - ®      Females – close to ovaries and cervix
• ureter - ®      Males – close to seminal vesicles
• ureter - ®      Has 3 layers: mucosal lining, muscular middle layer & fibrous outer layer
• urinary bladder - serves as a reservoir for urine
• ®      Muscular, collapisable bag – located directly behind the pubic symphysis
• ®      Lies below the parietal peritoneum – covers only superior surface
• ®      Remainder of bladder surface – covered a fibrous adventitia
• ®      Women – sits on the anterior of the vagina, infront of the uterus
• ®      Men – rests on the prostate
• ®      Detrusor Muscle – muscle layer formed by a network of crisscrossing bundles
• ®      Bundles runs in all directions: circular, oblique & lengthwise
• ®      Bladder is lined with mucous transitional epithelium that forms folds called “rugae”
• ®      Micturition – mechanism of urinating begins with involuntary contractions
• ®      Urination is also called “voiding the bladder or micturition”
• o     Nephrons – make up the bulk of each kidney / functional unit of the kidney
• 1.       Renal Corpuscle – made up of the glomerulus tucked inside the bowman capsule
• a.       Bowman Capsule – cup shaped mouth of the nephron
• bowman capsule - Formed by parietal and visceral walls