After exiting the collecting duct, urine enters the renal pelvis. The renal pelvis is part of the ureter and is found inside the medulla of the kidney. Numerous collecting ducts will pool into the renal pelvis, allowing urine to accumulate. After it exits the kidney (via the renal pelvis), urine enters the ureter where it is pushed towards the urinary bladder. In the bladder, urine is stored until it reaches a maximum threshold pressure and volume. Once this maximum is reached, the individual feels the urge to urinate and the process of urination begins. During urination, the urine is propelled via smooth muscle contraction from the urinary bladder to the urethra, and excreted from the body.

The basement membrane is negatively charged in order to repel other negatively charged substances, specifically proteins. This is important because it ensures that proteins don't enter the filtrate, which is eventually excreted as urine. Old or malfunctioning proteins can be broken down, and their amino acids can often be recycled. Excretion of protein molecules would be extremely unfavorable.

An obstructive kidney stone in a nephron would impact bulk forces and filtration. Specifically, it would affect the hydrostatic pressure in Bowman's capsule. As a result, the glomerular filtration rate would decrease due to increased hydrostatic pressure in the capsule opposing filtration. Consequenty, fluid would be prevented from being filtered out of the kidney.

The papillary duct forms from collecting ducts in the kidney, where it travels to the calyces in the renal pelvis and then out of the kidney (via the ureter) to the bladder. Here, it is stored until micturition (urination).

While internal and external sphincter muscles are used to expel waste, these are located in the anal canal, not the rectum. The rectum precedes the anal canal and serves as storage; it signals the nervous system when it is full and defecation is needed.

Diabetes results from an autoimmune destruction (type I) or dysfunction (type II) of pancreatic beta cells.

The Islets of Langerhans in the pancreas are made of acinar cells, which secrete various essential hormones. Alpha cells secrete glucagon, while beta cells secrete insulin. Delta cells secrete somatostatin and epsilon cells secrete ghrelin. Beta cells are the most abundant acinar cell.

The pancreas has two primary purposes, acting as both an endocrine gland and an exocrine organ. Islets of Langerhans secrete the endocrine factors, while the acinar cells produce the exocrine factors of the pancreas.

The Islets of Langerhans serve to secrete insulin, which promotes the absorption of glucose from the blood into cells throughout the body. The Islets also secrete glucagon, somatostatin, and ghrelin. Pepsin is produced by chief cells in the stomach, while trypsinogen (the zymogen of trypsin) is produced by acinar cells of the pancreas. Bicarbonate is produced in response to secretin secretion by acinar cells in the pancreas.

Essentially, pancreatic hormones are released from the Islets of Langerhans, while pancreatic digestive enzymes are released from the acinar cells.

Digestive precursor molecules are secreted by both the pancreas and chief cells of the stomach. The pancreas secretes trypsinogen, which is later cleaved to the active trypsin. Chief cells in the stomach secrete pepsinogen, which is then cleaved into the active pepsin. These precursor molecules are known as zymogens.

Although it is true that the hepatic artery is a branch or the celiac axis, or trunk, the liver has a dual blood supply in the form of the hepatic artery and the portal vein. The latter structure brings absorbed nutrients from the small and large intestine directly back to liver cells for processing.

The liver is vital in the control of blood glucose levels. It stores excess glucose by creating glycogen via the process of glycogenesis. It can also release glucose into the bloodstream by stimulating gluconeogenesis and glycogenolysis. Glycogenolysis is the process of converting glycogen back to glucose, while gluconeogenesis is the process of making glucose from non-carbohydrates.

Insulin is created in the pancreas, and is released in response to high blood sugar levels. The insulin then stimulates the liver to store glucose as glycogen.