Exam 3 - Urinary Sys.

Nephron Structures

100

PCT

Absorbs most filtrate and glucose, secretes waste into tubular fluid.

200

Loop of Henlee

Create salinity gradient that allows CD to concentrate urine and conserve water. 

300

DCT

Reabsorb some water and salt, regulated by hormones (aldosterone, ADH, ANP, parathyroid). Contain principal and intercalated cells. Release H+

400

Podocytes

Epithelial cells in the bowman's capsule. Use pedicels to wrap around capillaries and filter blood. (in the glomerulus)

500

Peritubular Capillaries

Receive blood from the efferent arteriole and return water, electrolytes and nutrients from tubular fluid to blood.

Structures

100

Glomerulus

Clump of capillaries that filter blood into filtrate and remove proteins.

200

Vasa Recta

Capillary branching off efferent arteriole. Provides blood supply to medulla but doesn't remove salt and urea.

300

Macula Densa

Patch of sensory cells in nephron loop. When GFR is high, Macula Densa absorbs NaCL and secretes ATP.

400

Juxtaglomerular Cells

AKA Granular cells. Respond to adenosine by constricting afferent arterioles to reduce blood flow and correct high GFR.

500

Mesangial Cells

As Macula Densa absorbs NaCL, cells metabolize ATP into adenosine, which stimulates nearby granular cells.

Hormones

100

Renin

Secreted by granular cells. When Na+ is low, renin acts on Angiotensin in the liver and triggers cascade.

200

Angiotensin

Turned into Angiotensin 1 in liver, then 2 in lungs. Triggers Aldosterone in adrenal gland.

300

Aldosterone

Secreted by adrenal gland. Triggered by low Na+, BP and BV. Kidneys increase Na+ and H2O reabsorption in blood while excreting K+

400

Atrial Natriuretic Peptide

Hormone secreted by atria in response to high BP, and BV. Inhibits RAAS and promotes salt loss and diuresis. Increases GFR.

500

ADH

Inhibits water loss in urine by reabsorbing water to blood via. aquaporin channels. Works with aldosterone to increase blood vol.