Which constraint reduces carbon fixation using Rubisco in desert plants?

💡 Explanation

Photorespiration competes with CO2 fixation by Rubisco, especially when O2 concentration is high due to stomata closure; therefore, photorespiration limits carbon fixation, rather than RuBP regeneration or chlorophyll deficiencies alone, because increased O2 favors Rubisco's oxygenase activity.

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• Which risk increases when foraging honeybees rely exclusively on outdated floral maps?
• Which osmoregulatory outcome is seen when saltwater fish drink seawater without sufficient chloride cell activity?
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• Which developmental consequence result when imaginal discs experience localized Hox gene repression during pupation in Drosophila?