Beginning of Essay
The first topic that was covered by this chapter was the excretion of wastes by the Renal system. The first step that occurs in the kidney deals with the nephron, which is the functional unit of the kidney. In the glomerulus the formation of urine begins with th ....

Middle of Essay
.... Active reabsortion is used to recapture glucose, proteins, amino acids and other nutrients. Water and chloride ions are passively reabsorbed by the establishment of osmotic and electrochemical gradients. Both the Loop of Henley and collecting duct are used to establish these osmolar gradients. The tubule has a brush border that will absorb proteins and polypeptides through pinocytosis. These molecules are sometimes catabolised and converted into amino acids. and returned to the blood. Sometimes the accumulation of these proteins can lead to renal toxicity A second process that occurs in the tubules is tubular secretion. This is another mechanis ....