Life Support for Plants

1. Life Support for Plants A72-75

2. Basic Needs of Plants • Air • Nutrients • Water • Soil

3. Why do plants need air? • There is carbon dioxide in the air. Leaves take in this carbon dioxide. • Carbon dioxide is one of the two main materials plants use to make food.

4. Why do plants need nutrients? • Just as animals need nutrients (vitamins and minerals) for growth, so do plants. • Soil provides plants with the nutrients they need to survive. • Plants cannot survive in soil that doesn’t have the necessary nutrients.

5. What about water? • Plants get water from rain. • Some of the water is absorbed through the plant leaves. • Most is absorbed by the roots.

6. Necessary Light • No plant can live in total darkness. • Some plants, however, may grow better in shaded areas.

7. Photosynthesis • Scientific name for the process by which a plant makes its own food • “Photo” means “Light” • “Synthesis” means “Putting Together” • Plants make food from light energy combined with carbon dioxide and water.

8. How does photosynthesis work? • Light + Carbon Dioxide + Water • Light is trapped by the chlorophyll. • Leaves take in carbon dioxide. • Roots take in water. • Water travels to leaves. • In the leaves, sugar is formed. • Oxygen is then released into the air by the leaves.

9. Plant Adaptations • Water plants grow from soil below the water, with stems growing toward surface • Vines grow on forest floors, but have stems climbing and clinging to other plants or objects for support and to get sunlight • Desert plants have thick stems that can store water for long periods; also have roots near surface, to absorb water quickly