Liver:

A dark reddish organ, the liver is the largest gland of the body. In an adult human, it weighs about 1.5 kg and is the size of a football. The liver lies beneath the diaphragm on the right side of the abdomen. It consists of a larger right lobe and a smaller left lobe.

Gallbladder:

A pear-shaped greenish-yellow sac, the gallbladder lies along the right lobe of the liver on the ventral side.

Secretion of Liver (Bile):

The liver secretes bile, which is stored in the gallbladder. When the gallbladder contracts the bile is released into the duodenum through the common bile duct. Bile has bile salts that keep lipid droplets separate from one another, a process called emulsification. It helps the lipid-digesting enzymes to attack lipids.

Role of Liver indigestion/Functions of Liver:

Besides digestion, the liver carries out several other functions, some of which are summarized here:

1. Removes amino groups from amino acids (de-amination)
2. Converts ammonia to a less toxic form the urea
3. Manufactures most blood plasma proteins e.g., prothrombin and albumin
4. Forms red blood cells in the fetus
5. Destroys the old red blood cells
6. Manufactures blood clotting proteins called fibrinogen
7. Synthesizes non-essential amino acids
8. Converts galactose and fructose to glucose
9. Converts glucose into glycogen and, when required, breaks glycogen into glucose
10. Converts carbohydrates and proteins into fats
11. Carries out the oxidation of fatty acids
12. Forms lipoproteins, cholesterol, and phospholipids
13. Synthesizes vitamin A from carotene, and activates vitamin D
14. Produces heat to maintain body temperature
15. Stores fat-soluble vitamins (A, D, E, and K) and mineral ions, such as iron.
16. Produces antiviral proteins e.g., Interferon