Functions of bacterial flora in the human gut

Question

Describe the main functions of bacterial flora in the human gut?

Answer 1

Bacteria which live within the gut contain great significance in digestion. Various polysaccharides such as cellulose, hemicellulose and pectin are not digested by digestive enzymes secreted by the body; rather, they are broken down by enzymes liberated by bacteria of the gastrointestinal tract. The intestinal bacterial flora also makes vital substances for the functioning of bowels facilitating or blocking the absorption of nutrients and stimulating or decreasing peristalsis. Various gut bacteria are the major source of vitamin K for the body and therefore they are necessary for the blood clotting process. In intestinal flora there are utile however as well potentially harmful bacteria. It is predicted that more than 100 trillion bacteria exist in a human gut. Certain bacteria are helpful too as they compete with other species preventing excessive proliferation of such bacteria.