(I wrote to you more than three types)
There are seven known types of human coronavirus. Four common types (KHUI, OC43, NL63,229E) cause mild to moderate respiratory infection, such as the common cold. There are two types, severe acute respiratory syndrome (SARS-COV) and Middle East respiratory virus syndrome (MERS-COV), that can cause acute respiratory infections. Type VII (nCOV-2019) is the newly discovered novel coronavirus in China.
It also reabsorbs water found in the undigested food
The alimentary canal includes mouth, esophagus, stomach, small intestine, and large intestine. As food passes through the alimentary canal, it is exposed to the different chemical secretions from the organs of the alimentary canal, as well as from other organs, such as liver and pancreas.
First, in the mouth, salivary glands produce saliva which <span>contains enzymes involved in the food digestions. After the food is passed to the esophagus, it produces mucus to help passage of the food. In the stomach, acid and pepsinogen, as well as mucus are produced. All of these secretions help food digestion. Small intestine also produces some digestive enzymes. Further, bile from liver and enzymes from pancreas are secreted via ducts into small intestine. Finally, large intestine secretes mucus for lubrication.</span>
