Energy and Ecosystems How Do Plants Produce Food? Plant Structures The three main parts of the plant are the roots, stems, and leaves. Each of these parts performs a specific job for the plant. Roots Name two of the most important jobs of roots? Roots help hold the plant in place. Roots absorb water and nutrients from the soil. Stems What are three important functions of stems? They hold the leaves up toward the sunlight. They contain vascular tubes that help transport water, food, and nutrients throughout the plant. They support the plant. Leaves What is the main job of a leaf? The main job of a leaf is to make food for the plant. Transpiration Stomata open to allow the leaves to absorb carbon dioxide. They close to keep the plant from drying out. The loss of water through leaves is called transpiration. Photosynthesis Photosynthesis is the process by which plants make food. What three elements are needed for photosynthesis to take place? Water, carbon dioxide, and sunlight Name two things that are produced by the process of photosynthesis? Sugar and oxygen Chlorophyll Plant cells contain a structure called chloroplasts that enable them to make food. Chloroplasts contain a green pigment called chlorophyll. Chlorophyll enables a plant to absorb light energy so that it can produce food. It All Starts With Plants All organisms need energy to live and grow. That energy comes from food. Plants are called producers because they produce or make their own food. Animals can’t make their own food, but they need energy to survive. Animals are called consumers because they eat or consume plants or other animals. How does this work? Discuss. How Does Energy Move? The energy from sunlight moves from plants, to animals that eat plants, to animals that eat other animals. Without sunlight, every living thing on Earth would die. Let’s Review 1. 2. 3. 4. What are the three main parts of plants? Name the functions of the following: roots, stems, and leaves. What is transpiration? Explain the process of photosynthesis.
