lesson 1: the digestive system
Why do we eat? Is eating necessary to stay alive? We need food to provide energy for moving about. Food also supplies the raw materials needed for growth and repair of body parts.
Body cells need food for energy, growth and repair. However, when food is eaten, it is not in a form that can be used by cells in the body. Food must be broken down into a form that cells can use. The body changes food into a usable form by means of a group of organs known as the digestive system
Parts and Functions
OBJECTIVES OF THE LESSON:
At the end of this lesson, learners are expected to demonstrate an understanding of: (1) the digestive system and its interaction with the circulatory, respiratory, and excretory systems in providing the body with nutrients for energy; and (2) diseases that result from nutrient deficiency and ingestion of harmful substances, and their prevention and treatment.