In the human digestive system, food enters the mouth and mechanical digestion of the food starts by the action of mastication (chewing), a form of mechanical digestion, and the wetting contact of saliva. Saliva, a liquid secreted by the salivary glands, contains salivary amylase, an enzyme which starts the digestion of starch in the food; the saliva also contains mucus, which lubricates the food, and hydrogen carbonate, which provides the ideal conditions of pH (alkaline) for amylase to work. After undergoing mastication and starch digestion, the food will be in the form of a small, round slurry mass called a bolus. It will then travel down the esophagus and into the stomach by the action of peristalsis. Gastric juice in the stomach starts protein digestion. Gastric juice mainly contains hydrochloric acid and pepsin. In infants and toddlers gastric juice also contains rennin. As the first two chemicals may damage the stomach wall, mucus is secreted by the stomach, providing a slimy layer that acts as a shield against the damaging effects of the chemicals. At the same time protein digestion is occurring, mechanical mixing occurs by peristalsis, which is waves of muscular contractions that move along the stomach wall. This allows the mass of food to further mix with the digestive enzymes.
Arts and soccer can combine, now that there so many sites in the internet that can provide you soccer drawings. You can find your favorite character in the internet. For example your favorite soccer players, soccer team, cartoon characters, soccer signs or symbols, flags and logos. And parents download some of their child's favorite soccer characters or icons in white background and in black ink. Then their children put some colors on it. Kids are excitingly put some colors on it specially those kids who love soccer. The parents who take great interest to engage their kids in the coloring pages also support in an array of other important elements like assisting in their decision-making, patience, endurance, and creativity. Youngsters' coloring pages on the web, supply a bigger assortment of subject matter than the books in the stores can, and if your kids desire published coloring books you can fire up that printer of yours and make a customized, one of a kind coloring book for your kid. It'll only take a little while to print out many coloring sheets, and these lead to hours of entertainment and brain stimulation for your child. oloring Pages are a great low cost and quick to set up activity for your kids to take part in. For example if your little darling declares that they want to do so, you just fire up the PC and internet connection, browse to a coloring page site and print out some pictures.