Lesson on Human Body – The Mouth for Primary 4

Hello, young learners! Welcome back to Primary 4 Basic Science Technology. In our previous lesson, we learned about Human Body – The Mouth IV. Today, we’re going to learn about the human body, specifically focusing on the mouth and its role in the digestive system.

Objectives

By the end of this lesson, you should be able to:

• Identify and describe the main parts of the alimentary canal.
• Develop an appreciation for the complexity and functionality of the human digestive system.
• Draw and label the alimentary canal.

The Alimentary Canal

The digestive system, also known as the alimentary canal, is a series of connected organs that work together to break down food so our body can absorb nutrients. It starts from the mouth and ends at the anus.

What is the Alimentary Canal?

The alimentary canal is a long, muscular tube that runs through the body, starting at the mouth and ending at the anus. It is responsible for the digestion of food, which involves breaking down food into smaller molecules that can be absorbed by the body.

Parts of the Alimentary Canal

There are several important parts of the alimentary canal, and they are:

1. Mouth: This is where digestion begins. The teeth chew the food, and saliva mixes with it to help break it down.
2. Esophagus: This is a muscular tube that connects the mouth to the stomach. It helps push the food down to the stomach.
3. Stomach: This is a muscular sac where food is churned and mixed with digestive juices. The stomach breaks down food further, making it easier to digest.
4. Small Intestine: This is a long, coiled tube where most nutrient absorption occurs. The small intestine is lined with tiny finger-like projections called villi, which increase the surface area for absorption.
5. Large Intestine: This is where water is absorbed from undigested food, and the remaining waste is formed into feces.
6. Rectum: This is the final part of the large intestine, where feces are stored before they are expelled from the body.
7. Anus: This is the opening at the end of the digestive tract where feces leave the body.

Evaluation Questions

Now that you’ve learned about the alimentary canal, let’s see if you can answer these questions:

1. What are the main parts of the alimentary canal?
2. What happens to food in the mouth?
3. What is the role of the small intestine in digestion?
4. Why is it important to eat a healthy diet?
5. Draw and label the alimentary canal.

Conclusion

Today, we learned about the alimentary canal and its important role in digestion. Remember, taking care of your digestive system is important for your overall health. Don’t forget to check the comments section if you have any questions, and use the navigation to move to the next lesson. See you in the next lesson!