Kidney Anatomy and Function PDF

# The Kidney ## Anatomy of the kidney - **Renal capsule:** prevents infection - **Adipose capsule:** cushions the kidney and helps attachment to the abdominal wall - **Renal fascia:** provides an anchor (is on outer layer of dense fibrous tissue) - **Pyramids of the Medulla:** - Renal columns...

# The Kidney ## Anatomy of the kidney - **Renal capsule:** prevents infection - **Adipose capsule:** cushions the kidney and helps attachment to the abdominal wall - **Renal fascia:** provides an anchor (is on outer layer of dense fibrous tissue) - **Pyramids of the Medulla:** - Renal columns - Pyramids - Collecting ducts - **Ureter:** - **Calyces:** collect urine - **Pelvis:** funnels urine into ureter - **Cortex:** ready brown ## The kidney's relation to other organs - **Aorta:** about 1/4 of all your blood goes through the kidneys in a minute - **Renal artery:** - **Renal vein:** - **Inferior vena cava:** - **Hilium:** - **Paired ureters:** take urine from the kidneys to the bladder - **Urinary Bladder:** provides temporary storage of urine until it's excreted. - **Urethra:** transports urine from the bladder to outside ## The Nephron - **Aorta:** - **Renal artery:** - **Nephron:** - **Glomerulus:** - **Afferent arteriole:** ## Details of the nephron - **Bowman's capsule:** cup-shaped end of the tubule that surrounds the glomerulus - **Glomerular capillaries:** allows filtrate to pass into the capsule (filtration) - **Renal capsule:** - **Peritubular capillaries:** low pressure, porous capillaries for tubular reabsorption - **Proximal convoluted tubule:** porous cells, 90% of water reabsorbed in PCT - **Loop of Henle:** water & useful substances are moved into capillaries by osmosis - **Distal convoluted tubule:** - **Collecting duct:** empty into the minor calyx ## Functions of the kidney - **Nephrons:** kidneys have a million nephrons - **Tubular secretion of:** creatinine, uric acid, urea, water ## Homeostasis and the kidney - **When plasma osmolarity increases:** - Osmoreceptors in the hypothalamus become irritated - Release ADH from the posterior pituitary gland into the blood - **ADH (control)** - drinking quenches thirst - **Mucosa of mouth, throat, stomach, and intestines become moist (end)** - control of fluid volume - **Lower BP** - control of blood pressure - **Renin:** renin, angiotensin, aldosterone: sodium + water - **From DCT:** increase fluid volume - **Increase BP** - **ADH causes nephrons to become more porous (more holes):** - **More H2O into surrounding capillaries:** less urine is produced! - **So more water moves out of the tubules and into the peritubular capillaries:** raising/decreasing osmolality