|MadSci Network: General Biology|
Any elementary book on nutrition, or numerous magazine articles about diet, nutrition, etc. would answer this question. Basically, the process of digestion hydrolyzes proteins into the constituent amino acids, which are then absorbed in the small intestine of all mammals. Amino acids are simple diffusible substances, the "buiding stones" that animals and man will use to reconstruct its own large specific protein molecules, Protein is needed for growth, weight maintenance, repairs tissues including replacing blood plasma and hemoglobin, heals wounds, resists trauma and infection, and fatty degenertation and cirrhosis of the liver are essentially prevented. Poor health and even death can occur without proper protein nutrition.
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