Friday, July 6, 2012
1. Liver - made up of thousands of lobules.
2. Each lobule - consists of rows of liver cells (hepatocytes).
- channels where blood flows
- from the hepatic artery
- into the hepatic vein.
4. Hepatic vein:
- carries deoxygenated blood + nutrients
- to the heart.
5. Hepatic portal vein:
- carries blood-containing nutrients
- from intestine
- into lobules.
- where bile secreted by the liver cells flows
- into bile duct.
7. Liver performs many important functions, all of which contribute to homeostasis:
i. Carbohydrate + protein metabolism
ii. site of synthesis of lipid (from excess glucose).
iii. detoxification - where drugs, toxins and poisons
(taken in the diet/produced by bacteria)
biochemically broken down + rendered harmless.
iv. production of bile + plasma proteins,
v. storage site of ions, minerals + vitamins
vi. generation of heat
8. In the liver: glucose is oxidized à to CO2 + H2O.
9. In the liver cells (stimulated by insulin)
à excess glucose is converted to glycogen (glycogenesis),
10. When the levels of blood glucose drop
à glycogen is converted to glucose (presence of glycagon).
11. When glycogen ↓ in the liver cells is depleted and glucose↓ level fall
à glucose is made from other non-carbohydrate sources = gluconeogenesis.