Quadrants and regions of abdomen in the context of Tenderness (medicine)

The liver is a major metabolic organ exclusively found in vertebrates, which performs many essential biological functions such as detoxification of the organism, and the synthesis of various proteins and various other biochemicals necessary for digestion and growth. In humans, it is located in the right upper quadrant of the abdomen, below the diaphragm and mostly shielded by the lower right rib cage. Its other metabolic roles include carbohydrate metabolism, the production of a number of hormones, conversion and storage of nutrients such as glucose and glycogen, and the decomposition of red blood cells. Anatomical and medical terminology often use the prefix hepat- from ἡπατο-, from the Greek word for liver, such as hepatology, and hepatitis.

The liver is also an accessory digestive organ that produces bile, an alkaline fluid containing cholesterol and bile acids, which emulsifies and aids the breakdown of dietary fat. The gallbladder, a small hollow pouch that sits just under the right lobe of liver, stores and concentrates the bile produced by the liver, which is later excreted to the duodenum to help with digestion. The liver's highly specialized tissue, consisting mostly of hepatocytes, regulates a wide variety of high-volume biochemical reactions, including the synthesis and breakdown of small and complex organic molecules, many of which are necessary for normal vital functions. Estimates regarding the organ's total number of functions vary, but is generally cited as being around 500. For this reason, the liver has sometimes been described as the body's chemical factory.

The umbilical region is one of the nine regions of the abdomen. It is the region that surrounds the area around the umbilicus and is placed approximately halfway between the xiphoid process and the pubic symphysis. This region of the abdomen contains part of the stomach, the head of the pancreas, the duodenum, a section of the transverse colon and the lower aspects of the left and right kidney. The upper three regions, from left to right, are the left hypochondriac, epigastric, and right hypochondriac regions. The middle three regions, from left to right, are the left lumbar, umbilical, and right lumbar regions. The bottom three regions, from left to right, are the left inguinal, hypogastric, and right inguinal regions.