Anatomy and Physiology: Renal Physiology

1) filter blood plasma2) Regulate blood volume:3) Regulate osmolarity of body fluids:4) Secrete homeostatic enzymes and hormones5) Maintains acid-base balance in blood

-separate waste from useful products-eliminate waste (urine) and reabsorb the rest to the plasma

-eliminating excess water, conserving when necessary

-controlling relative amounts of electrolyte and other solutes that are eliminated-#solutes/liter= osmolarity (osmols/L or miliosmols/L)

-Renin to stimulate Renin-Angiotensin mechanism for Na+ and H20 homeostasis-Erythropoietin (EPO) which controls red blood cell count to aid O2 transport in blood"blood doping"

-maintains bicarbonate concentration in plasma

Excretion-The process of separating wastes from body fluids and eliminating them as urine~waste is any substance that is useless to the body or present in excess of the body's needs

-toxins, drugs, hormones (assists liver)-salts(electrolytes), H+, excess H2O-metabolic wastes

Returning water and solutes from the tubular fluid to the blood

Waste substance produced by the body-CO2, H+, nitrogenous wastes

-Toxic waste products of metabolism that contain nitrogen-excess nitrogen in the blood (usually ammonia or urea) can lead to diarrhea, vomiting and shortness of breath~long duration (>few days) of excess levels of nitrogen in blood leads to convulsions, coma, death

-Ammonia-Urea-Uric Acid-Creatinine

NH3 -major source comes from amino acid deamination-very toxic to the body

-liver converts the toxic NH3 to urea because urea is less toxic than ammonia but it is still toxic-elevated blood urea nitrogen (BUN) levels may indicate renal insufficiency

-formed by the metabolism of nucleic acids(DNA and RNA)-crystalizes and becomes gout in joints