What is the liver?The liver is a large reddish brown solid organ that sits in the upper part of the abdomen, tucked away under the right side of the rib cage. Above it is the heart and the right lung, and it is separated from them by a thin sheet of muscle called the diaphragm. Your liver is probably four to five times the size of your fist.
The liver has two halves or lobes, the right lobe and the left lobe, but the right lobe is larger than the left; roughly the right lobe is 60-65% of the liver. Blood flows into the liver through two large blood vessels that enter it from below – the hepatic artery which brings blood rich in oxygen, pumped out from the heart, and the portal vein which brings blood flowing out of the gut, rich in absorbed food material.
Blood flows out of the top of the liver through three large veins called the hepatic veins, into a big vein called the inferior vena cava or IVC that goes to the heart. Below the liver, where the hepatic artery and the portal vein come in, the bile duct comes out of the liver. Bile made in the liver flows out through this bile duct (which is a thin tube the size of a drinking straw), and goes down to the gut, where it mixes with food. The gall bladder is a small greenish pear-shaped bag that hangs off the bile duct. It stores bile and squeezes it out into the gut at mealtime.