Students investigate photosynthesis. They determine that oxygen gas is produced by plant leaves in light but not in darkness. They come to understand that the Sun is the source of energy for plants and that plants are the primary source of matter and energy for all living things. Students learn that this energy is captured in sugars during photosynthesis and then stored in the form of starch. Students test various foods for starch and learn which plant parts are used for starch storage. Finally, students learn that oxygen and carbon dioxide cycle in the environment.

Student Resources

• 2.1 Vocabulary
• 2.2 Photosynthesis
• 2.3 Observing Photosynthesis in Elodea
• 2.4 Observing Photosynthesis in an Ivy Cutting
• 2.5 The Oxygen-Carbon Dioxide Cycle
• 2.6 Do Plants Carry Out Photosynthesis in the Dark?
• 2.7 Testing for Starch
• 2.8 Section 2 Assessment

Learn by Reading

For additional content-area reading, check out the Houghton Mifflin Science eBook: Grade 4, Unit B, pages 24 and 26.