FFA Horticulture CDE General Practice Exam

What part of the plant is responsible for photosynthesis?

1. Roots

2. Stems

3. Leaves

4. Flowers

The correct answer is: Leaves

The leaves are the primary sites for photosynthesis in plants. This process occurs in the chloroplasts, which contain chlorophyll, the green pigment essential for capturing light energy from the sun. During photosynthesis, leaves take in carbon dioxide from the air and water from the soil to produce glucose and oxygen, using sunlight as energy. The structure of leaves is particularly adapted for this purpose; they have a large surface area to maximize light absorption, and many contain tiny pores called stomata that facilitate the exchange of gases. This makes them ideally suited to carry out the complex biochemical reactions involved in photosynthesis. While other parts of the plant, such as stems and flowers, play important roles in reproduction and nutrient transport, they do not engage in photosynthesis to the same extent as leaves. Roots are primarily involved in water and nutrient uptake and do not participate in the photosynthetic process.