Excess cholesterol and phospholipids are eliminated in the bile Liver produces bile which contains water, bile salts and bile acids to help emulsify fat Bile is transported in the bile canaliculi to the bile duct Detoxification: DETOXIFICATION: the conversion of toxic molecules to less toxic or non-toxic molecules. The liver is able to detoxify many compounds Some of these compounds, such as hydrogen peroxide, are produced in the body Some compounds, such as alcohol, may be consumed as a part of our diet Others, such as drugs, may be taken for health reasons or recreational purposes Toxins can be rendered harmless by oxidation, reduction, methylation or combined with another products Liver cells contain many enzymes that render toxic molecules less toxic E.g. catalase, which converts hydrogen peroxide to oxygen and water Catalase has a high turnover number – the number of molecules of hydrogen peroxide that one molecule of it can render harmless in one minute – of 5 million. Detoxification of alcohol: Alcohol, or ethanol, is a drug that depresses nerve activity It contains chemical potential energy, which can be used for respiration It is broken down in the hepatocytes by ethanol dehydrogenase The resulting compound is ethanal This is dehydrogenised further by the enzyme ethanal dehydrogenase The final compound produced is ethanoate (acetate), which is combined with coenzyme A to form acetyl coenzyme A, which enters the process of respiration The hydrogen atoms released in this process are combined with another coenzyme called NAD to form NADH NAD is also required to oxidise and breakdown fatty acids for use in respiration If the liver has to detoxify too much alcohol it has insufficient NAD to deal with the fatty acids These fatty acids are then converted back to lipids and are stored in hepatocytes, causing the liver to become enlarged This is a condition known as ‘fatty liver’ which can lead to alcohol related hepatitis or to cirrhosis This is when the cells of the lover die and scar tissue blocks blood flow The Kidney: Describe, with the aid of diagrams and photographs, the histology and gross structure of the kidney. Describe, with the aid of diagrams and photographs, the detailed structure of the nephron and its associated blood vessels.
Excess cholesterol and phospholipids are eliminated in the bile Liver produces bile which contains water, bile salts and bile acids to help emulsify fat Bile is transported in the bile canaliculi to the bile duct Detoxification: DETOXIFICATION: the conversion of toxic molecules to less toxic or non-toxic molecules. The liver is able to detoxify many compounds Some of these compounds, such as hydrogen peroxide, are produced in the body Some compounds, such as alcohol, may be consumed as a part of our diet Others, such as drugs, may be taken for health reasons or recreational purposes Toxins can be rendered harmless by oxidation, reduction, methylation or combined with another products Liver cells contain many enzymes that render toxic molecules less toxic E.g. catalase, which converts hydrogen peroxide to oxygen and water Catalase has a high turnover number – the number of molecules of hydrogen peroxide that one molecule of it can render harmless in one minute – of 5 million. Detoxification of alcohol: Alcohol, or ethanol, is a drug that depresses nerve activity It contains chemical potential energy, which can be used for respiration It is broken down in the hepatocytes by ethanol dehydrogenase The resulting compound is ethanal This is dehydrogenised further by the enzyme ethanal dehydrogenase The final compound produced is ethanoate (acetate), which is combined with coenzyme A to form acetyl coenzyme A, which enters the process of respiration The hydrogen atoms released in this process are combined with another coenzyme called NAD to form NADH NAD is also required to oxidise and breakdown fatty acids for use in respiration If the liver has to detoxify too much alcohol it has insufficient NAD to deal with the fatty acids These fatty acids are then converted back to lipids and are stored in hepatocytes, causing the liver to become enlarged This is a condition known as ‘fatty liver’ which can lead to alcohol related hepatitis or to cirrhosis This is when the cells of the lover die and scar tissue blocks blood flow The Kidney: Describe, with the aid of diagrams and photographs, the histology and gross structure of the kidney. Describe, with the aid of diagrams and photographs, the detailed structure of the nephron and its associated blood vessels.
excretion.docx