The kidneys are two bean shaped blood filtering organs. The kidney’s primary function is the elimination of waste from the bloodstream through the production of urine.
Homeostasis thing that kidneys do:
- maintain volume of extracellular fluid
- maintain ionic balance in extracellular fluid
- maintain pH and osmotic concentration of the extracellular fluid.
- excrete toxic metabolic by-products such as urea, ammonia, and uric acid
They are located on the sides in the retroperitoneal space
In adult humans are a kidney is about 12 centimeters in length.
The kidneys receive blood from renal arteries, and blood exits into the paired renal veins
each kidney is attached to a ureter, a tube that carries excreted urine into the bladder.
kidneys use nephrons
there are over 1 million nephrons in each kidney which act as filters
The kidneys filter needed materials and waste. Needed materials go back into the bloodstream; unneeded materials become urine and are expelled through the urethra.
excess wastes crystallize as kidney stones. they grow and can become painful irritants that may require surgery or ultrasound treatments. Some stones are small enough to be forced into the urethra