Aldosterone
Diuretics are the class of drug used to regulate the level of fluid in the body. They work by increasing urine production and decreasing the blood volume that must be pumped throughout the body.
Kidneys mostly function to filter the blood of waste. This also allows the kidneys to filter electrolytes to regulate their levels.
removes waste and regulate blood
The adrenal glands
No, excess joint fluid is not removed from the body by the kidneys. Joint fluid, also known as synovial fluid, is produced by the synovial membrane in the joints and is primarily reabsorbed back into the bloodstream through lymphatic vessels. The kidneys primarily filter waste products from the blood and regulate fluid balance in the body.
Potassium
potassium
They help regulate blood pressure (I think)
Kidneys regulate the body's fluid volume, mineral composition and acidity by excreting and reabsorbing water and inorganic electrolytes. This helps balance these substance (which include sodium, potassium, chloride, calcium, magnesium, sulfate, phosphate and hydrogen) in the body and keep their normal concentrations in the extracellular fluid.
The kidneys control pH by secreting or reabsorbing H+ ions.
There are many functions of the kidneys that maintain homeostasis. In addition to filtering wastes, the kidneys use hormones to regulate blood pressure and altering the sodium and electrolyte balances to maintain proper fluid balances within the body. The kidneys help to maintain the internal balance in the body by excreting substances that change that balance. The kidneys also help to maintain water balance.