12- The roles of the Liver Flashcards
How many lobes does the liver contain
4
Where is the liver located
Located in the upper right hand part of the abdomen behind lower ribs.
What are the 3 main functions of the liver
Metabolism- Control of synthesis and utilisation of carbohydrates, lipids and proteins
Secretory and Excretory Functions- synthesis and secretion of bile and detoxification
Vascular Function- formation of lymph and hepatic phagocytic system
What processes does the liver carry out to maintain blood glucose levels
Glycogenesis
Glycogenolysis
Gluconeogenesis
What is glycogenesis
When excess glucose is taken up by the liver and stored by glycogen
What is gluconeogensis
When hepatic glycogen reserves are depleted, glucose is synthesised from amino acids and non-hexose carbs
What is glycogenolysis
When blood glucose levels decline there is depolymerisation of glycogen to glucose
What does the liver do in terms of lipid metabolism
Convert products of carb metabolism to fatty acids and lipids that can be stored in adipose tissues
Synthesise large quantities of cholesterol and phospholipids.
What happens to protein in the liver.
The amine group is first converted into ammonia which is toxic and then converted to urea.
Urea is non toxic and excreted from the body by the kidneys (a component of urine)
What is transamination
Amine group can also be transferred via transamination to make new amino acids
What is the one protein in plasma that isn’t metabolised by the liver
Immunoglobulins
Where is the majority of liver blood supply received from
Venous- via hepatic portal vein
What do hepatocytes have to remove substances from blood
An array of transporters
What are the 2 main functions of bile
Important for digestion and absorption of fats and fat-soluble vitamins
Many waste products, including bilirubin are secreted into bile and excreted in the faeces
What does amphipathic mean and what does this mean for bile
Contains both hydrophilic and hydrophobic faces
Lipid centre with a hydrophilic outer layer.
