Nephrons – Rhymes with Efron The Nephron Filtering cells of the kidney Over 1 million per kidney!! Most in cortex Some extend from cortex to medulla Produce urine Nephrons – Rhymes with Efron 1

Renal Corpuscle 2 parts 1. Glomerulus (part of the blood flow) - high pressure, porous capillary bed - allow solute-rich fluid to pass from blood -into glomerular capsule - under high pressure - forces materials smaller than proteins into the Bowman’s Capsule 2. Bowman’s capsule 3

Blood Vessels of the Nephron and Kidney Glomerulus Fed and drained by arterioles Afferent arteriole—arises from tiny branches of the renal artery, brings blood to the nephron Efferent arteriole—receives blood from the nephron See page 520 figure 15.2c

Efferent arteriole moves out of the Bowman’s capsule and becomes the peritubular capillaries Peritubular capillaries surround the nephron tubule (PCT, Loop of Henle, DCT) Reabsorption occurs here Peritubular capillaries drain into venules and eventually branch into the renal vein

Parts of the Nephron Bowman’s Capsule 1st part of the nephron surrounds the glomerulus Collects “filtrate”

Renal Tube Extending from Bowman’s capsule For absorption of various materials back into the peritubular capillaries Contain microvilli 3 parts 1. Proximal convoluted tubule (PCT) 2. Loop of Henle 3. Distal convoluted tubule (DCT) Bowman’s capsule

Collecting Duct (collecting tubule) Receives urine from multiple nephrons Many collecting ducts run through the medullary pyramids to calyx and finally renal pelvis