Bio 431 Urinary system Exam A+ Pass

Bio 431 Urinary system Exam A+ Pass Regulation of blood volume, osmolarity, & composition Regulation of BP, pH, & blood glucose levels Hormone production Waste & foreign substance excretion Urine transport (ureter), storage (bladder), & release (urethra) - Answer- Function of Kidney, ureters, bladder, & urethra Renal A., Segmental A., Interlobular A., Arcuate A., Cortical Radiate A., Afferent A., Glomerular capillaries, efferent arterioles, peritubular capillaries, peritubular venules, Cortical Radiate veins, Arcuate veins, Interlobular veins, Renal veins - Answer- blood flow of kidney Renal Nerves - Answer- innervate kidneys and ureters regulate blood flow sympathetic Nephrons - Answer- filtering units of the kidney that remove wastes from the blood and produce urine in the millions has renal corpuscle and renal tubule renal corpuscle - Answer- has glomerulus and bowman's capsule glomerulus - Answer- A ball of capillaries surrounded by Bowman's capsule in the nephron and serving as the site of filtration in the vertebrate kidney. fed by afferent arterioles (wider) and drained by efferent arterioles bowman's capsule - Answer- cup-shaped structure of the nephron of a kidney which encloses the glomerulus. visceral layer- podocytes that wrap around the glomerulus parietal layer- forms the space around visceral layer filtrate is collected between these layers mesangial cells - Answer- contractile cells that help regulate glomerular filtration glomerular endothelial cells - Answer- have large fenestrations through which solutes pass Basal lamina - Answer- lies between endothelium and podocytes pedicels - Answer- Filtration slits in the outermost layer of the filtration membrane made by podocytes. mostly protein-free plasma - Answer- filtrate cortical nephrons - Answer- 85% of nephrons; almost entirely in cortex Renal corpuscles are in outer cortex with short loops of Henle Drain blood to peritubular capillaries Create urine with osmolarity similar to blood Juxtamedullary Nephrons - Answer- 15% of nephrons; Next (close to) medulla Renal corpuscles are deep in cortex with long nephron loops Drain blood to peritubular capillaries & vasa recta Enable kidney to secrete very concentrated urine Juxtaglomerular (JG) Apparatus - Answer- Located between ascending loop & the afferent arteriole regulates blood pressure in the glomerulus (autoregulation) Asc. loop contains macula densa cells Aff. arteriole contains smooth muscle cells called juxtaglomerular cells 1.Glomerular Filtration 2.Reabsorption 3.Secretion - Answer- Steps in Urine filtration Excretion rate of solute - Answer- filtration rate of solute + secretion rate of solute − reabsorption rate of solute Glomerular Filtration - Answer- Driven by blood pressure (aka GBHP)& opposed by capsular hydrostatic pressure (CHP) & blood colloid osmotic pressure (BCOP) 150-180 liters of filtrate/day Net Filtration Pressure (NFP) - Answer- the difference between net hydrostatic pressure and net osmotic pressure GBHP-CHP-BCOP Glomerular filtration rate (GFR) - Answer- the amount of filtrate formed by both kidneys each minute 125 ml/min (males) & 105 ml/min (women) High GFR - Answer- substances pass too quickly & are not reabsorbed Low GFR - Answer- nearly all substances are reabsorbed & waste excretion is inadequate Renal Autoregulation Neural Regulation Hormonal Regulation - Answer- regulators that controls GFR Renal Autoregulation - Answer- nephrons adjust their own blood flow and GFR without external (nervous or hormonal) control Myogenic mechanism of Renal Autoregulation - Answer- Smooth muscle cells in afferent arterioles contract in response to elevated blood pressure decrease GFR