Classed as part of the digestive system, the liver's roles include detoxification, protein synthesis and the production of chemicals necessary for digestion.1
This article will cover the main roles of the liver, how the liver regenerates, what happens when the liver does not function correctly and how to keep the liver healthy.
Contents of this article:
Here are some key points about the liver. More detail and supporting information is in the main article.
- The liver is classed as a gland
- The liver carries out more than 500 roles in the human body
- It is the only organ that can regenerate
- The liver is the largest solid organ in the body
- Carbohydrates are broken down and stored as glycogen in the liver
- One of the liver's tasks is to remove toxins from the body
- Alcohol abuse is one of the major causes of liver problems in the industrialized world
- Both yellow fever and malaria affect the liver
- Albumin is produced in the liver and helps prevent blood vessels from becoming "leaky."
Structure of the liver
The liver has a rubbery texture to the touch and appears reddish-brown.
Weighing between 1.44 and 1.66 kg, the liver is reddish-brown in hue with a rubbery texture; it is situated above and to the left of the stomach and below the lungs. The skin is the only organ that is heavier and larger.
The liver is roughly triangular in shape and consists of two lobes, a larger right lobe and a smaller left lobe. The lobes are separated by the falciform ligament - a band of tissue that keeps it anchored to the diaphragm.
A layer of fibrous tissue called Glisson's capsule covers the outside of the liver. This capsule is further covered by the peritoneum, a membrane that forms the lining of the abdominal cavity; this helps hold the liver in place and further protects it from physical damage.
Unlike most organs, the liver has two major sources of blood. Firstly, the portal vein brings it nutrient-rich blood from the digestive system. Secondly, the hepatic artery carries oxygenated blood from the heart.
The blood vessels divide into small capillaries, with each terminating in a lobule. Lobules are the functional units of the liver and consist of millions of hepatic cells (hepatocytes).
Blood is removed from the liver via three hepatic veins.
On the next page, we look at the functions of the liver and its remarkable ability to regenerate.