Question 77

Plants require carbon dioxide to produce sugars through photosynthesis.

Photosynthesis is the process by which plants convert carbon dioxide and water into glucose and oxygen using sunlight. Therefore, carbon dioxide is essential for the production of sugars.

A) Nitrogen

Nitrogen is not directly involved in the photosynthesis process. While it is an essential nutrient for plants as it contributes to amino acids and proteins, it does not serve as a gas required for the synthesis of sugars during photosynthesis.

B) Oxygen

Oxygen is a byproduct of photosynthesis rather than a reactant. During the photosynthesis process, plants release oxygen into the atmosphere after converting carbon dioxide and water into glucose, which means oxygen is not required for sugar production.

C) Carbon dioxide

Carbon dioxide is the critical gas that plants use in photosynthesis to create sugars. It is absorbed from the atmosphere and, along with water and sunlight, is transformed into glucose, making it an indispensable component of the photosynthetic process.

D) Helium

Helium is an inert gas that does not participate in any biological processes, including photosynthesis. It does not play any role in the production of sugars or any other compounds in plants.

Conclusion

The correct answer is carbon dioxide, as it is the key gas that plants utilize in photosynthesis to synthesize sugars. All other options are either unrelated to the photosynthetic process or serve different purposes in plant biology, confirming that carbon dioxide is the only viable choice for this question.