Part one of term paper
In vertebrates, are the two major organs of excretion. Excess water, toxic waste products of metabolism such as urea, uric acid, and inorganic salts are disposed of by in the form of urine. are also largely responsible for maintaining the water balance of the body and the pH of the blood. Kidneys play important roles in other bodily fun ...

Part two of term paper
... tissue. It is believed that the kidney first evolved in the original vertebrates where freshwater organisms needed some means of pumping water from the body. The kidney became adept at reabsorbing glucose, salts, and other materials which would have been lost if simply pumped out of the body by a simple organ. The cut surface of the kidney reveals two distinct areas: the cortex- a dark band along the outer border, about one centimeter in thickness, and the inner medulla. The medulla is di ...