Choose one physical digestive process and one chemical digestive process. Briefly describe how each process works, including the body parts where the processes occur and any other organs or substances involved.

Physical Digestive Process: Chewing

Chewing is the first step in the physical digestion process. It occurs in the mouth where the teeth break down food into smaller pieces. This process is also known as mastication. The tongue and saliva also play a role in this process. The tongue helps to move the food around while saliva moistens the food making it easier to swallow. Chewing increases the surface area of the food to allow for more efficient break down by digestive enzymes later in the digestive process.

Chemical Digestive Process: Enzymatic Breakdown

The enzymatic breakdown of food is a key chemical digestive process. This process begins in the mouth with the enzyme amylase (found in saliva) starting to break down complex carbohydrates into simpler sugars. However, the majority of enzymatic digestion occurs in the stomach and small intestine. In the stomach, gastric juice (containing hydrochloric acid and the enzyme pepsin) breaks down proteins. Then, in the small intestine, pancreatic enzymes and bile further break down proteins, fats, and carbohydrates. The end result of this process is the conversion of food into small, nutrient molecules that can be absorbed into the bloodstream.

Physical Digestive Process: Chewing

Chewing is the first step in the physical digestion process. It occurs in the mouth where the teeth break down food into smaller pieces. This process is also known as mastication. The tongue and saliva also play a role in this process. The tongue helps to move the food around while the saliva moistens the food making it easier to swallow. Chewing increases the surface area of the food to allow for more efficient break down by digestive enzymes later in the digestive process.

Chemical Digestive Process: Enzymatic Breakdown

The enzymatic breakdown of food is a key chemical digestive process. This process begins in the mouth with the enzyme amylase (found in saliva) starting to break down complex carbohydrates into simpler sugars. However, the majority of enzymatic digestion occurs in the stomach and small intestine. In the stomach, gastric juice (containing hydrochloric acid and the enzyme pepsin) is released to break down proteins. Then, in the small intestine, pancreatic enzymes and bile (produced by the liver and stored in the gallbladder) further break down proteins, fats, and carbohydrates. The end result of this process is the conversion of food into small, nutrient molecules that can be absorbed into the bloodstream.