Question 8

Plants need carbon dioxide from the environment to conduct photosynthesis.

Carbon dioxide is a crucial molecule that plants absorb from the atmosphere, which they convert into glucose during the photosynthesis process. This gas, along with sunlight and water, is essential for the synthesis of food in plants.

A) Sugar

Sugar is the product of photosynthesis, not a requirement for the process itself. While plants do utilize sugar for energy and growth, they do not need it from the environment to conduct photosynthesis.

B) Carbon dioxide

Carbon dioxide is vital for photosynthesis, as it is one of the primary substrates that plants use to produce glucose. During this process, plants take in carbon dioxide through their stomata and use it, along with sunlight and water, to synthesize their food.

C) Oxygen

Oxygen is a byproduct of photosynthesis rather than a necessary input. While plants release oxygen during the photosynthetic process, they do not require it from their environment to perform photosynthesis.

D) ATP

ATP (adenosine triphosphate) is an energy carrier produced during photosynthesis, but it is not taken from the environment. Instead, it is synthesized within the plant cells as a result of the photosynthetic process itself.

Conclusion

Carbon dioxide is the definitive correct answer because it is the essential molecule that plants extract from the environment to perform photosynthesis. The other options, while related to the process, do not serve as necessary inputs for photosynthesis, thus confirming that they are incorrect.