If C₄ Photosynthesis Prevents Photorespiration, Why Haven?t All Plants Evolved

question 26

Multiple Choice

If C₄ photosynthesis prevents photorespiration, why haven?t all plants evolved to use the C₄ pathway?

• A) All plants will evolve to be C₄ in time.
• B) C₄ produces some toxic by-products.
• C) Only some plants use C₄ photosynthesis.
• D) C₄ is not advantageous in all climates.
• E) C₄ is advantageous only in high-oxygen habitats.

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