Excretion is the removal of metabolic waste products from cells.

1. Carbon dioxide
2. Urea

Haemoglobin from old red blood cells is broken down in hepatocytes in the liver into bile pigments. 

The bile pigments are then transported via the bile duct to the gall bladder where they are stored before their removal from the body.

Hepatocytes have large nuclei, a prominent Golgi apparatus, and several mitochondria.

Hepatocytes in the liver convert glucose to glycogen when blood glucose levels increase.

They also convert glycogen back to glucose when blood glucose levels decrease.

Deamination is the removal of an amine group from a molecule.

In the liver, deamination involves the removal of the amine group from excess amino acids to form ammonia.

The remainder of the amino acids can be used in cellular respiration or converted into lipids for storage.

The ornithine cycle is a set of enzyme-controlled reactions during which ammonia reacts with carbon dioxide and is converted into urea.

Urea is then transported to the kidneys to be removed from the body as a part of urine.

1. The liver detoxifies hydrogen peroxide - hepatocytes contain the enzyme catalase that splits hydrogen peroxide into oxygen and water
2. The liver detoxifies alcohol - hepatocytes contain the enzyme alcohol dehydrogenase that breaks down the ethanol to ethanal, which is then converted to ethanoate
3. The liver detoxifies ammonia - the ornithine cycle converts ammonia into urea

Kupffer cells ingest pathogens and other foreign particles, helping to protect against disease.

1. Hepatic portal vein - transports blood with the products of digestion from the intestines to the liver
2. Hepatic artery - transports oxygenated blood to the liver
3. Hepatic vein - transports deoxygenated blood from the liver towards the heart

The blood from the hepatic artery and the hepatic portal vein mixes in the sinusoids, supplying oxygen and nutrients to the hepatocytes.