Welcome to this lesson today on chewing and swallowing. Today, you will be learning about the processes of chewing and swallowing as they are involved in food digestion. Specifically, you will learn about:
The actions of the mouth are the first step in digestion and involve the chewing and swallowing of food. Within the mouth we have two forms of digestion that are occurring, mechanical digestion and chemical digestion. Both are happening in your mouth at the same time to help break down food as the first step in digestion before it reaches the stomach. We're going to take a look at what the difference between these two types of digestion are and where they occur in the mouth.
Mechanical digestion is the digestive process that physically breaks down food. Mechanical digestion occurs by physical movements of various digestive organs. In your mouth, an example of mechanical digestion would be when you are chewing and your teeth physically break the food down.
Chemical digestion also occurs in your mouth and is when chemicals break down the food. Chemical digestion in your mouth is carried out by enzymes and enzymes play a role throughout your whole digestive system in chemical digestion.
One specific enzyme in your mouth that's very important is called salivary amylase. Salivary amylase is an enzyme secreted by your salivary glands within your mouth that help break down starches in the foods that you eat into simple sugars.
As you're chewing food, your tongue will push the food against your palate, which is also known as the roof of your mouth, and mix it with saliva. Once the mouth is done mechanically and chemically digesting the food, it is then swallowed; the chewed ball of food that is swallowed is called a bolus.
As food is swallowed, it will move down toward your stomach via peristalsis. Peristalsis is characterized by wave-like contraction of the muscles of the digestive tract that propels food throughout it, including the esophagus. Your esophagus will contract just above the bolus and push it downward. Then, a new contraction will go above it again and push it downward farther.
Peristalsis also acts in other parts of the digestive system as well aside from the esophagus. Peristalsis is also how your intestines push food through your digestive tract.
So this lesson has been an overview on chewing and swallowing and their role in digestion. Specifically, you looked at the role of the mouth, the differences between mechanical and chemical digestion, and the role of the peristalsis.
Keep up the learning and have a great day!
Source: THIS WORK IS ADAPTED FROM SOPHIA AUTHOR AMANDA SODERLIND
The physical breakdown of food into smaller pieces.
The chemical breakdown of food by enzymes or chemicals.
Glands in the mouth which release saliva to aid in the chemical digestion of foods while you chew.
An enzyme found in saliva that chemically breaks down starches into single sugars.
The ball of chewed food that is swallowed.
Also known as the "roof" of your mouth; The tongue presses food against the palate and mixes it with saliva to break it down before swallowing.
Covers the larynx during swallowing to prevent food or liquids from entering the lungs.