1. TROPISM NEXT

2. . There are three main types of tropisms : Phototropism Geotropism Hydrotropism TROPISM refers to plant growth in response to something in its surroundings.

3. GEOTROPISM Geotropism is the growth of a plant in response to gravity. Positive Geotropism Plant grows down with gravity. Ex. roots growing down Negative Geotropism is the growth of a plant opposite to the pull of gravity Ex. stems grow up NEXT Positive Geotropism Negative Geotropism * Geo means earth.

4. IMPORTANCE OF GEOTROPISM NEXT Pulls roots down to anchor a plant Roots can get needed water and minerals if they stay in the soil

5. PHOTOTROPISM Plant growth toward a source of light is PHOTOTROPISM. NEXT (“Photo” – light) Ex. Stems growing toward the window to get to the light

7. IMPORTANCE OF PHOTOTROPISM NEXT Lets leaves be in the best position possible to receive enough light for photosynthesis http://www.darienps.org/teachers/otterspoor/botany/tropism s/Gravitropismwlight.jpg

8. Hydrotropism Hydro means water. Hydrotropism refers to a plant growing toward a source of water. This allows the plant to stay alive and to do photosynthesis.