Cud stretched, forming a vacuum in the gullet that sucks the semi-liquid stomach content into the esophagus. From the esophagus it is taken back to the mouth with retro peristaltic movements. When the stomach content, or the cud, arrives in the mouth of the ruminant, it is pushed against the palate with the tongue to remove excess liquid, the latter is swallowed and the solid material is chewed thoroughly so the cattle can extract the minerals present in the cud brought to the surface during rumination. The function of rumination is that food is physically refined to expose more surface area
Chewing gum modern cities, free of gum. Various teams of researchers have developed gum that is less adhesive and degrades within days or weeks. One example, Rev7 Gum, was briefly for sale from 2010 to 2012. Many schools do not allow chewing gum because students often dispose of it inappropriately (leaving it under desks and chairs, behind vending machines, etc.). The chewing may also pose a distraction to class, and the gum might carry diseases or bacteria from other students. The Singapore government outlawed chewing gum in 1992 citing the danger of discarded gum being wedged in the sliding doors of underground