Liver

  • Created by: farahh24
  • Created on: 06-09-18 14:32
View mindmap
  • Liver
    • Functions of the Liver
      • Carbohydrate metabolism
        • When blood sugar is too high, the liver produces insulin. This instructs the body to convert glucose into glycogen
        • When blood sugar is too low, the liver produces glycogen. This instructs the body to convert glycogen into glucose.
      • Protein metabolism
        • Hepatocytes are responsible for producing most of the body's plasma.
          • This plasma is used for transamination - the process of converting low demand amino acids into amino acids with higher demands
      • Detoxification
        • Hepatocytes produce a large number enzymes that break down toxins
          • For example, hydrogen peroxide is broken down by catalase into water and oxygen
          • For example, ethanol is broken down by  ethanol dehydrogenase into ethanal, by removing a hydrogen.
            • Ethanal is broken down by ethanal dehydrogenase into ethanoate, which can be used in respiration
              • The co-enzyme NAD is used in this process. It's original purpose is to oxidise fatty acids for respiration.
                • However, if too much alcohol is ingested, the co-enzyme prioritises breaking ethanol down into ethanoate. Fatty acids are instead converted into lipids, and build up in the liver.
                  • The lipids are stored in the hepatocytes. This affects their ability to produce proteins efficiently. Eventually, the nucleus will be destroyed to make more room for the lipids. This means the cells can no longer reproduce.
      • Deamination
        • Protein are hydrolysed by proteases into amino acids, which are then absorbed from the small intestine and into the liver.
          • Excess amino acids are deaminated by removing the amine group. The amine group becomes ammonium, which enters the ornithine cycle, and the remainder of the amino acid becomes keto acid, which aids respiration
            • The Ornithine Cycle
    • Cirrhosis
      • Healthy liver tissue is replaced with scarred tissue. This may be caused by:
        • Alcoholic fatty liver disease
          • This means bile cannot reach the lower intestine, toxins in the blood cannot be broken down, _____________
        • Alcoholic hepatitis
        • Liver cirrhosis
  • Untitled

Comments

No comments have yet been made

Similar Biology resources:

See all Biology resources »See all Health, illness and disease resources »