Question

multiple choice 5 points
the diagram below shows the gas exchange among different organisms.
which carbon compound is represented by the x?
carbon dioxide, co₂
carbonic acid, h₂co₃
glucose, c₆h₁₂o₆
carbon monoxide, co

Explanation:

Step1: Recall gas exchange in organisms

Plants (like sunflower) take in \(CO_2\) for photosynthesis. Animals (like turkey, grasshopper) respire and release \(CO_2\).

Step2: Analyze each option

• Carbon dioxide (\(CO_2\)): Sunflower can take in \(CO_2\) (for photosynthesis) and animals release \(CO_2\) (from respiration). This fits the gas - exchange cycle in the diagram.
• Carbonic acid (\(H_2CO_3\)): It is not a gas involved in the simple gas - exchange cycle shown (between plant and animals) in the diagram. It is more relevant in aqueous solutions (e.g., in blood or rainwater reactions).
• Glucose (\(C_6H_{12}O_6\)): It is a solid (in the context of plant - animal gas exchange) and is a product of photosynthesis (not a gas exchanged in the way shown in the diagram).
• Carbon monoxide (\(CO\)): It is a toxic gas. There is no biological process in the simple plant - animal gas - exchange (as depicted) that involves the release of \(CO\) by animals or uptake by plants in a normal, healthy cycle.

Answer:

Carbon dioxide, \(CO_2\)