As food is pushed along, it undergoes digestion. Digestion is the process of breaking down food into nutrients. There are two types of digestion: mechanical digestion and chemical digestion. Mechanical digestion occurs when large chunks are turned into smaller chucks. Perhaps not surprisingly, this happens when you chew your food. Once you swallow the food, your stomach also does some of this work. Chemical digestion occurs when food is broken down into useful nutrients. This is a chemical process that begins as you start to chew your food. The saliva in your mouth starts this process. Once you swallow, the acid in your stomach further breaks down food. From the stomach, the foods moves into the small intestine. In the small intestines, another set of chemicals goes to work. Are you surprised? Your small intestine, and not your stomach, does most of the work!

Question: "Where do foods move into from stomach?"

Response: "Large intestines"

A: no

Plants also detect the daily cycle of light and darkness. Do you know how plants respond to these changes? Some plants open their leaves during the day. It is during these hours the plant can collect sunlight. At night, the plant closes its leaves to prevent water loss. Many plants respond to the change in the length of the day. As days grow shorter, some plants respond by going dormant. Dormant is when a plant suspends its growth. It does this in order to survive. Shorter days signal the coming of winter. Winter in most areas means extreme cold. It is also very dry in the winter months. As winter approaches, some plants respond by their leaves changing color. After the change in color, they fall off. This dormancy period helps trees. It allows them to survive the cold and dry winter. Plants only want to grow when conditions are right.

Question: "What are two ways we might suspect a tree has become dormant?"

Response: "Its leaves have changed color and it dies"

A: no

The world can be divided into three climate zones. The first climate zone is the polar zone. As it sounds, the polar zone is near earths poles. The polar zone has very long and cold winters. Brrr!!!! Near the equator is the tropical zone. The tropical zone is known for being hot and wet. Between these two zones is the temperate zone. Temperatures there tend to be mild. Its not too hot and not too cold. You might expect places near the equator to be hot and wet. Thats not always the case. Sometimes there are other factors at work. These factors can affect the local climate type or a region. Oceans and mountain ranges can have a major impact. They can greatly influence the climate of an area. Many factors influence an areas climate.

Question: "Which of the 3 climate zones is near the earths poles?"

Response: "Temperature"

A:
no