Digestion Story

Digestion Story

Hi my name is carby and I’m a carbohydrate. I was just eaten by a human, and I’m gonna take you through the process that unfolded just now. Firstly I ended up in the human’s mouth otherwise known as the oral cavity. Mechanical digestion began as their teeth started to chew me. Saliva was being released by the three pairs of salivary glands we have. Saliva contains an enzyme called salivary amylase which breaks me down, and lubricates me so I’m easier to swallow. The tongue makes me into a bolus and pushes me to the pharynx. As I move to the pharynx I go past a large punching bag shaped object called the epiglottis. The epiglottis acts as a director of the food into the trachea so that no food goes down the windpipe. I now am swallowed and make my way down the esophagus. Peristalsis pushes me down the esophagus in rhythmic contractions. At the bottom of the esophagus I reach the cardiac sphincter. The cardiac sphincter acts as a valve that contracts to prevent acid reflux, and relaxes to allow the travel of food like me. Once I’m in the stomach it begins to churn. The churning along with the release of acid and enzymes breaks me down into even smaller molecules. The stomach is very acidic, and a thick layer of mucous protects the lining of it. The physical digestion in the stomach occurs when it churns periodically to break down food. The chemical digestion in the stomach occurs when acids, and enzymes are released. After being converted to a substance called chyme by HCl, I leave the stomach through the pyloric sphincter. The pyloric sphincter controls the flow of partially digested food from the stomach to the small intestine. Just like the cardiac sphincter, it relaxes to allow me to pass through into the duodenum which is part of the small intestine. An enzyme called pancreatic amylase