L26 - kidney structure & blood filtration

• kidneys • ureter • bladder • urethra

• regulation of water, salts, acid-base balance • removal of metabolic waste • removal of foreign chemicals • gluconeogenesis (formation of glucose) • production of hormones/ enzymes

• erythropoietin (rbc production) • renin (controls bp + na balance) • activates vitamin D (regulates ca)

• outside is capsule • then the cortex • the little shell shapes are medulla • the middle bit is the renal pelvis • the tube thing is the ureter

• each nephron feel into collecting ducts • which feed into ureter • functional unit of kidney

• top half • glomerulus, bowmans capsule • PCT • DCT

• loop of henle • collecting duct

• glomerulus, bowmans capsule • PCT • descending loop of henle • ascending • DCT • collecting duct

• afferent arteriole : blood with waste in • efferent arteriole: clean blood out

• glomerular filtration • tubular secretion • tubular reabsorption

• podocytes surround blood vessels within glomerulus • sieve like structures • allow free passage of small molecules from blood to kidney tubules

• fluid filtered through glomeruli by pressure of flow through blood vessels • regulated by adjusting blood pressure either side of glomerulus • so kindeys maintain water + salt balance

volume of fluid filtered from glomeruli to bowman’s space per unit time

• reducing pressure in glomerulus reduces GFR • constrict afferent vessels • dilate the efferent • reduces water + salt loos through excretion

• increases GFR • constricting efferent vessels • dilating afferent vessels • increases salt + water excretion

40L

no its filtered out but then reabsorbed