ISA Certified Arborist Practice Exam

What is the importance of tree leaves in photosynthesis?

1. They absorb carbon dioxide and provide shade

2. They capture sunlight and convert it to energy

3. They store water and nutrients

4. They protect the tree from pests

The correct answer is: They capture sunlight and convert it to energy

The significance of tree leaves in photosynthesis primarily lies in their ability to capture sunlight and convert it into energy. During the process of photosynthesis, leaves utilize chlorophyll, the green pigment contained within them, to absorb light energy from the sun. This light energy is then harnessed to convert carbon dioxide from the atmosphere and water from the soil into glucose, a form of sugar that serves as energy and nourishment for the plant. Additionally, this process releases oxygen as a byproduct, which is essential for the survival of most living organisms. By converting sunlight into chemical energy, leaves play a crucial role in the ecosystem, supporting not only the growth of the tree but also contributing to the overall balance of atmospheric gases. This core function emphasizes the indispensable role of leaves in sustaining plant life and, by extension, the health of the environment.