The kidneys are very important organs found not only in humans, but also many other animals. And each person contains two identical and symmetrical kidneys. So the function of the kidney we're going to focus on in the next several lectures. The kidneys basically function in not only in excretion, but also in controlling and regulating the osmolarity of our blood plasma. Now, in this lecture, we're going to focus on the basic anatomy and structure of the kidney. So let's begin by taking a cross section of any one of our kidneys.