Unit 6 Lesson 3 How Do Plants Respond to Their Environment? Copyright © Houghton Mifflin Harcourt Publishing Company

Florida Benchmarks SC.3.N.1.6 Infer based on observation. Unit 6 Lesson 3 How Do Plants Respond to Their Environment? Florida Benchmarks SC.3.N.1.6 Infer based on observation. SC.3.L.14.2 Investigate and describe how plants respond to stimuli (heat, light, gravity), such as the way plant stems grow toward light and their roots grow downward in response to gravity. Copyright © Houghton Mifflin Harcourt Publishing Company

Unit 6 Lesson 3 How Do Plants Respond to Their Environment? Plants and Light The environment is all the living and nonliving things in a place. Plants respond to their environments. One way that plants respond to their environment is by growing toward light. Growing toward light helps plants make more food. Copyright © Houghton Mifflin Harcourt Publishing Company

Unit 6 Lesson 3 How Do Plants Respond to Their Environment? Plants and Light Flowering plants respond to light in more than one way. Some flowers open during the day and close at night. Other flowers close during the day and open at night Sunflowers follow the sun as it moves across the sky. Copyright © Houghton Mifflin Harcourt Publishing Company

Unit 6 Lesson 3 How Do Plants Respond to Their Environment? The Heat Is On! Plants respond to the temperature of their environment. Leaf budding is one way that plants respond to temperature. When the weather is warm, the buds come out. Copyright © Houghton Mifflin Harcourt Publishing Company

Unit 6 Lesson 3 How Do Plants Respond to Their Environment? The Heat Is On! Temperature affects when seeds germinate. Germinate means that the seeds start to grow. Some plants germinate when the weather is warm. Some pinecones do not release their seeds until after a forest fire. Copyright © Houghton Mifflin Harcourt Publishing Company

Unit 6 Lesson 3 How Do Plants Respond to Their Environment? Cold Snap Plants respond to cold weather. Temperature below 0 °C, or a freeze, can harm a plant. If a freeze occurs when the plant is flowering, the flowers die. The plant does not produce fruit. Copyright © Houghton Mifflin Harcourt Publishing Company

Unit 6 Lesson 3 How Do Plants Respond to Their Environment? Cold Snap If a freeze occurs when fruit is on the plant, the fruit is ruined. Sometimes, the fruit can be saved by spraying it with water. Ice forms on the fruit and protects it. Copyright © Houghton Mifflin Harcourt Publishing Company

Up or Down? Plants respond to gravity. Unit 6 Lesson 3 How Do Plants Respond to Their Environment? Up or Down? Plants respond to gravity. A plant’s roots grow downward, and its stem grows upward in response to gravity. Even if you tip a plant on its side, its stem will grow up and its roots will grow down. Copyright © Houghton Mifflin Harcourt Publishing Company