Urinary System - Exam 4 Flashcards
system includes what organs
kidneys, ureters, urinary bladder, urethra, genital organs
function of kidney
removing waste products from the blood & eliminating them as urine
hilium
medial side of each kidney, includes the renal artery, renal vein, lymphatics, nerve supply, & ureter
ureter
carries the final urine from the kidney to the bladder
bladder
store urine until micturition
inner medulla
divided into renal pyramids, terminates in the papilla, renal pelvis space
renal pelvis space
continuation of ureter, major & minor calyces, contractile to propel urine to the bladder
functions of urinary system
regulation of water & electrolyte balance, body fluid osmolality & [electrolyte], arterial pressure, acid-base balance, RBC production, secretion/metabolism/excretion of hormones, gluconeogenesis
regulation of water & electrolyte balance
capacity to alter Na+ excretion in response to changes in [ECF] or [plasma]
regulation of arterial pressure: long term
excrete Na & H2O
regulation of arterial pressure: short term
secreting hormones (renin) that lead to secretion of vasoactive substances (angiotensin II)
regulation of acid-base balance
excrete acids, regulate body fluid buffer stores, eliminate sulfuric acid & phosphoric acid
regulation of RBC production
secrete erythropoietin -> stimulates production of RBC by hematopoetic stem cells in the bone marrow (severe kidney leads to anemia)
regulation of Vitamin D3 production
produce active form of vitamin D (calcitriol, essential for calcium reabsorption by the GI tract, important role in Ca/P regulation)
glucose synthesis
from amino acids and other precursors during prolonged fasting (gluconeogenesis)
nephron
functional unit of the kidney, each nephron capable to form urine (don’t regenerate)
glomerulus
tuft of glomerular capillaries, large amounts of fluid are filtered from the blood, covered by epithelial cells, encases in Bowman’s capsule
tubule
filtered fluid is converted into urine
proximal tubule
cortex, from here fluid moves into loop of henle, each loop has a descending & ascending limb
ascending limb
returns partway back to cortex, thick, macula densa
distal tubule
renal cortex, connecting tubule, cortical collecting tubule & collecting duct, pyramidis
cortical nephrons
outer cortex, short loop of henle
justaglomerular nephrons
20-30%, deep in contex, long loop of henle, long efferent arterioles extend from the glomeruli down into the outer medulla, divide into vasa recta
vasa recta
specialized peritubular capillaries
