AP BIOLOGY

Detailed explanation-1: -The pharynx is a passageway for food and air. A soft flap of tissue called the epiglottis (pronounced: ep-ih-GLAH-tus) closes over the windpipe when we swallow to prevent choking. From the throat, food travels down a muscular tube in the chest called the esophagus (pronounced: ih-SAH-fuh-gus).

Detailed explanation-2: -Mouth. Food starts to move through your GI tract when you eat. When you swallow, your tongue pushes the food into your throat. A small flap of tissue, called the epiglottis, folds over your windpipe to prevent choking and the food passes into your esophagus.

Detailed explanation-3: -The term bolus applies to this mixture of food and solutions until they are passed into the stomach. Once the bolus reaches the stomach, mixes with gastric juices, and becomes reduced in size, the food mass becomes known as chyme.

Detailed explanation-4: -Mechanical digestion in the oral cavity consists of grinding of food into smaller pieces by the teeth, a process called mastication. Chemical digestion in the mouth is minor but consists of salivary amylase (ptyalin, or alpha-amylase) and lingual lipase, both contained in the saliva.

Detailed explanation-5: -The mouth is the entry point for food. The mouth is the entry point for food, but the digestive system often gets ready before the first piece of food even enters our mouth. Saliva is released by the salivary glands into our oral cavity when we smell food.