Mechanical digestion is a process that begins the second the food particles reach the mouth. Teeth initiates mechanical digestion by grinding the food up which is a process called masticating, or simply just chewing.
Chemical digestion is a process when your saliva helps soften the food into a mush-type texture. Salivary amylase enzyme helps digesting the carbohydrates and mucus. This process helps the food particles become smaller to help you swallow.
After swallowing, the food goes through a process which requires chemical and mechanical treatment. Inside the stomach mechanical digestion will help churn the food bolus, whereas the chemical process will mix the bolus with digestive juices released by the stomach lining cells.
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