WHAT IS THE ROLE OF THE LIVER IN THE MAINTENANCE OF A CONSTANT LEVEL OF MATERIALS IN THE BODY. (20mks))

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 What is the role of the liver in the maintenance of a constant level of materials in the body. (20mks) 
  • Regulation of blood sugar level; under the influence of insulin; and glucagon (hormones). 
  • When there is excess sugar; the hormone insulin stimulates liver cells to convert it to glycogen; some blood sugar is converted to fats for storage; 
  •  When the blood sugar level is below normal: the hormone glucagon stimulates liver cells to convert glycogen to glucose; 
  •  Regulation of amino acids; excess amino acids; are deaminated; by the liver (cells) leading to formation of urea; which is transported by the blood to the kidney; for elimination;  
  • Production of heat: the liver is involved in the thermoregulation due to many metabolic, activities; taking place in the liver cells a lot of heat is generated which is distributed to the entire body; 
  •  Detoxification of toxic substances; (such as drugs and hydroxide peroxide) 
  • Elimination of haemoglobin; and formation of bile; breakdown worn out red blood cells; the bile 
  • salts (sodium tyrocholate and sodium glycocholate); in the bile emulsify fat (in the duodenum)
  •  Storage of blood in its veins; thus regulating the volume of blood circulating in the body 
  •  Elimination of sex hormones after they have performed their functions; storage of vitamin A,  D and B12, some mineral salts; thus regulating their levels in the blood.

 TOTAL 23 MAX 20

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