urinary system

• nitrogenous wastes
• toxins
• drugs
• regulate aspects of homeostasis (water balance, acid base balance, blood pressure, vit D activation)

overall water balance (water and sold content in the body remain constant)

equals osmolarity of intracelllular fluid

balancing intake and excretion of sodium with that of water

any chemical compound that produces ions when dissolved in water

help maintain acid base balance and water balance

• kidneys monitor and regulate levels of hydrogen ions and bicarbonate ions in the blood to control blood pH
• H+ byproduct of dietary protein metabolism and accumulates in blood over time

• the stregnth of blood pushing against sides of blood vessels 
• kidneys monitor blood pressure

kidneys produce renin, a hormone which restricts blood vessels and produces concentrated urine (allowing more water to remain in the blood)

• EPO = hormone produced by kidneys to stimulate the production of red blood cells 
• if blood doesn't have enough oxygen, EPo released

• kidneys play role in turning vitamin D into active form Calciferol 
• helps balance calcium and phosphorus levels by controlling the absorption of these minerals 
• Parathyroid hormones (PTH) regulates calcium homeostasis and bone

• T12 to L3
• against dorsal body wall 
• right lower than left 
• adrenal gland on top of kidney

• kidneys
• ureters
• urinary bladder
• urethra

• renal cortex - (90% of blood flow) and all glomeruli found here
• renal medulla - inside of cortex
• renal pelvis - inner collecting tube, turns into ureter

• medullary pyraminds 
• renal columns 
• calyces (cup shaped funnel urine)

• functional unit 
• form urine
• glomerulus 
• renal tubule

each kidney

• one way to measure remaining kidney function 
• process where kidneys filter blood, removing excess wastes in fluid 
• 120ml/min

glomerulus is primary site for filtration

• where glomerular filtrate collects
• filtrate = H2O, glucose, salts, and urea

• blood comes to kidney from renal artery 
• transferred to afferent arteriole
• filtrated in glomerulus 
• filtered carried out by efferent arteriole

2/3 nutrient reabsorption takes place in the proximal convoluted tubule

• water reabsorbed passively (passive transport) 
• descending loop is impermeable to Na

• reabsorbed via active transport (Na, K, Cl) 
• secretion (and reabsorption) of NA and Cl is controlled by aldosterone

• reabsorb Na and H2O 
• secrete K

chemical waste product in the blood that passes through the kidneys to be filtered and eliminated in urine

regulates the osmotic pressure of body fluids by causing the kidneys to increase water reabsorption in the collecting ducts

makes collecting ducts more permeable to water

• in hypothalamus 
• detect changes in osmotic pressure 
• dehydration causes osmotic pressure to increase
• cells are called sensors

• sends message to pituitary gland 
• relsease ADH
• hypothalamus acts as co ordinating center
• PT gland is effector/regulator

• lowers osmotic pressure 
• more concentrated urine

• osmoticreceptors detect changes in osmotic pressure
• causes osmotic pressure to decrease

more common in women because of shorter urethra

• dehydration is major risk for kidney stones
• 80% kidney stones are calcium based

stimulates small intestines for protein synthesis

overactive bladder