The urinary system or the renal system is responsible to help us to maintain in the state of homeostasis. The kidneys are the major organ in the urinary system that regulate the balance of fluid volume, stabilize the pH level, regulate the ion concentration in the plasma, perform reabsorption of useful nutrients, and also eliminate waste, toxin, and harmful byproducts from our system in the form of filtrates and later on being processed as urine. And within the kidneys, the nephron, which is the functional unit of the kidneys, consists of renal corpuscle made up by glomerulus and the Bowman’s capsule and the tubular passageways, where the filtration, reabsorption, and secretion occur to form the urine. The purpose of this experiment is to observe and determine how different drinks affect the urinary system in term of the pH level, urine volume, and specific density of the urine. In order to make hypothesis to each of the measurements; three significant hormones should be introduced because of their function to regulate the renal system, and they are the antidiuretic hormone (ADH), Aldosterone, and the Atrial natriuretic peptide (ANP). ADH is a protein hormone that is being synthesized in the hypothalamus and secreted by the posterior pituitary gland in response to the increase of the blood osmolality. Releasing of the ADH can increase the water absorption, so it will decrease the formation of urine. Another hormone called the ANP is released by the heart when being triggered by the increase of the sodium concentration in the plasma. Atrial natriuretic peptide can increase the excretion of sodium and water, and the production of the urine will increase as the consequence. Last but not least, the third hormone that plays the role in regulating the function of the urinary system is the aldosterone from the adrenal gland. It is triggered by the decrease of the sodium level in the plasma. It stimulates the reabsorption of sodium and water, and therefore; lowering the production of urine. After having a basic knowledge of the anatomy and the functions of the renal system, and also the hormones that regulate nephron, hypothesis can now be made regrading to the four experimental groups in this experiment which are the non-drinking group, and the individual group who has ingested water, coke, and gatorade after being dehydrated for 5 hours, so all participants will be at the same base-line.?The urine volume (flow rate) is the first thing that will be measured within the four different groups. The hypothesis of this first measurement is that the Gatorade group will have the highest urine flow rate or expect urine volume. One of the reasons for this prediction is due to the property of the Gatorade, which it is containing the highest concentration of sodium when comparing to coke and water. Before the ingestion of any substances; all participants are being at the same base-line, which is dehydrated. And as the result of the dehydration; ADH and Aldosterone hormones is elevated due to the increase of the blood osmolarity and the decrease of the plasma sodium concentration. On the other hand, ANP level will increase due to the decrease of the sodium level. However, after the ingestion of the Gatorade, the osmolarity of the plasma will become hypo-osmotic due to the electrolytes in the Gatorade, which will cause the plasma volume and the blood pressure to rise. As the blood pressure and plasma volume increase, it creates the distension to the heart atrial chamber which causes the release of the atrial natriuretic peptide hormone to increase the excretion rate of sodium. And since the excretion of excess sodium will also lead to the excretion of water due to osmosis; therefore, more urine production will be achieve which causes the urine flow rate or urine volume to be the highest. Another factor to be considered when making hypothesis to the urine flow rate in this experiment is that glucose level will also contribute to the increasing level of the urine volume because water is one of the products that is being generated when there is a breakdown of the glucose molecule, and since coke has the highest concentration of glucose comparing to Gatorade and water, it can interfere with the hypothesis or the result in turn of which drinking group will have the highest urine volume.?Solute concentration or the specific density is the second data that is collected in this experiment. The hypothesis of this second measurement is that the non-drinking group will have the highest solute concentration in the urine. The non-drinking group maintains dehydrated throughout the entire experiment causing the plasma volume and the blood pressure to decrease. Decreasing of the blood pressure will lead to lower filtration rate due to lesser amount or frequency of blood is being reached to the glomerulus for diffusion to occur with the Bowman’s capsule. This will cause the blood osmolarity to increase significantly. Osmoreceptor cells in the hypothalamus will be activated due to the increasing level of blood osmolarity. Then the antidiuretic hormone will be released from the posterior pituitary and transported to the kidney, and causing the collecting duct to be permeable to water. Lastly, due to the high osmosis in the medulla region of the kidney, water will move outfrom the collecting duck to the region with greater osmotic pressure or higher concentration of solute since ADH has enhanced the permeability of the collecting ducts to the water molecules resulting with the higher reabsorption of water; therefore, the non-drinking group will have the highest solute concentration or specific density because their urine has the lowest urine flow rate or urine volume but greater concentration of solute. ?The last hypothesis about the acidity or pH level of urine is that the non-drinking group will have the most acidity pH level.Non- drinking group will have the most acidity urine because it has much higher concentrated urine. As the explanation from the solute concentration or the specific density experiment; dehydration will inhibit the release of ANP because of the decreasing level of sodium in plasma, and it will enhance the release of ADH. As the result, reabsorption of water will increase due to the ADH hormone increases the permeability of collecting duct to water molecules. On the other hand, decreasing of the release of ANP will limit the secretion of sodium and water causing the specific density of the urine to be much higher than drinking group because specific density is the measurement of the amount of solute within liter of water in the urine. Therefore, although Coke and Gatorade are being considered as acidic drink with the pH range of 2 to 2.5 for coke and 2.5 to 3, it will increase the release of ANP hormone as the result of increasing plasma sodium. ANP hormone from the heart will promote the excretion of sodium, and the water also since excretion of excess sodium is followed by the excretion of water; therefore, the urine will be more diluted given from the above hypothesis that they will have a higher urine flow rate or expected urine volume.