Outline and explain the various homeostatic functions of the liver in mammals

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Deamination; process of removal of an amino group from an amino acid molecule; the process gets rid of excess amino acids in the body; as the body is not able to store them; the amino group combines with hydrogen to form ammonia. Ammonia enters the ornithine cycle; where it is combined with carbon (IV) oxide to form urea; which is excreted in urine through the kidney; 
Heat production; many metabolic activities take place in the liver; releasing heat energy; that is distributed by the blood to other parts of the body; this contributes to thermoregulation; 
Storage of vitamins and mineral salts; Vitamins A, B, D, E and K; are stored in the liver; Amounts of vitamins need to be regulated. 
Worn-out red blood cells, are broken down to yield iron; which is stored in the liver in form of ferritin; this is used later in case of shortage; 
Formation of red blood cells; occurs in the liver of the foetus; 
The liver also breaks down old/exhausted red blood cells; leading to formation of more in the bone marrow to replace the worn-out cells; to enhance oxygen and carbon (IV) oxide distribution; 
Regulation of blood sugar level; liver cells convert excess glucose into glycogen and fats under the influence of insulin hormone; the stored glycogen is however converted back to glucose; when glucose levels are low; by the liver cells; under the influence of glucagon hormone; 
Regulation of plasma proteins; plasma proteins such as prothrombin and fibrinogen are manufactured in the liver using the amino acids found in the liver; they play a major role in blood clotting; that prevents excessive blood loss and infection at the injured area; other plasma proteins produced by the liver such as serum and albumen; contribute to the maintenance of osmotic pressure in the body; 
Non-essential amino acids are also synthesized by the liver; for use by the body; 
Storage of blood; the liver is highly vascularised; hence it is capable of holding a large volume of blood when the blood vessels dilate during hot conditions; when the temperatures are low, the blood vessels constrict under the influence of the endocrine and nervous systems; hence less blood is stored in the liver; this contributes to thermoregulation; 
Detoxification; this is the process where harmful compounds such as drugs and poisons; are converted to less toxic compounds in the liver; toxicity is caused by medication, drugs and microorganisms; the toxic compounds are later excreted in urine; detoxification prevents the accumulation of toxins in body cells; which could lead to death or malfunctioning of the body cells; Max. 20 mks

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