LIVER structure and introduction 0.0 / 5 ? BiologyCellular processes and structureA2/A-levelOCR Created by: Steff06Created on: 09-03-16 10:49 What does the liver produce? Important chemicals and bile. 1 of 28 What does the liver breakdown? Toxins and old erythrocytes. 2 of 28 What do hepatocytes do? Carry out metabolic processes. 3 of 28 What does the liver have an important role in? Homeostasis 4 of 28 Where is the liver supplied blood from? Oxygenated blood from the heart and deoxygenated blood from the digestive system. 5 of 28 How does the oxygenated blood from the heart reach the liver? Travels from the aorta via the hepatic artery into the liver. Oxygen is essential for aerobic respiration and to produce ATP. 6 of 28 How does deoxygenated blood from the digestive system reach the liver? Via the hepatic portal vein. 7 of 28 How does blood leave the liver and where does it go? Leaves via the hepatic vein and enters the vena cava. 8 of 28 What carries bile away from the liver and where does it take it to? Bile duct carries bile to the gall bladder where it is stored until required to aid digestion of fats. 9 of 28 What is the liver divided into and what are these subdivided into? Liver divided into lobules which are further divided into cylindrical lobules. 10 of 28 What does each lobule contain? Many vertical rows of hepatocytes arranged around the central blood vessel called the central vein. 11 of 28 Describe the structure of each lobule. Each lobule is a 6-sided structure consisting of specialised epithelial cells called hepatocytes. 12 of 28 How are the lobules arranged? Arranged in irregular, branching, interconnected plates around the central vein. 13 of 28 What are sinusoids and where are they located? Vessels within the hepatic portal vein. 14 of 28 What are sinusoids adapted for? The exchange of materials between the blood flowing through sinusoids and the hepatocytes. 15 of 28 What is the difference between sinusoids and normal capillaries? Sinusoids are wider and have a slower blood flow. The walls are more porous and the are composed of 1 layer of thin cells. 16 of 28 Last question continued... There is no basement membrane and many pores between the cells. Blood flowing through sinusoids is in close contact with surrounding hepatocytes. 17 of 28 What are kupffer cells are where are they located? Fixed phagocytes in the sinusoids. They move around in the sinusoids. 18 of 28 What is the key role of kupffer cells? To break down and recycle old erythrocytes. 19 of 28 What is the product of this breakdown? Bilirubin which is excreted as part of bile and in faeces. 20 of 28 What does the bile duct transport? Bile from the liver to the gall bladder. 21 of 28 What is a main function of the liver? To manufacture bile. 22 of 28 Where are bile canaliculi situated? Running alongside the sinusoids. 23 of 28 What do bile canaliculi do? Carry bile from the centre of the lobule to outside where it enters the branch of the bile duct. 24 of 28 Why do levels of nutrients in the body need to be controlled? So that their levels do not become harmful. 25 of 28 What can excess glucose and excess iron cause? Excess glucose can cause osmotic stress and excess iron can causes iron deposits in tissues. 26 of 28 What can excess vitamin D cause? Elevated calcium levels, anorexia, nausea and kidney failure. 27 of 28 What is wrong with an excess vitamin A? An excess can be fatal. 28 of 28
Comments
No comments have yet been made