Live Quiz Arena
🎁 1 Free Round Daily
⚡ Enter ArenaQuestion
← Nature & AnimalsWhich outcome occurs when PEP carboxylase activity exceeds rubisco’s fixation rate in C4 plants' carbon fixation pathways?
A)Photorespiration rate is minimized
B)Stomata close to regulate water loss
C)ATP demand for pathway increases✓
D)Initial carbon fixation decreases
💡 Explanation
When PEP carboxylase activity exceeds rubisco’s rate, the C4 pathway efficiently captures CO2 into oxaloacetate, increasing the concentration around rubisco and preventing photorespiration, but the conversion processes increase ATP consumption. Therefore higher ATP usage results, rather than minimized photorespiration, stomatal closure which involve separate mechanisms related to water balance, or decreased carbon fixation.
🏆 Up to £1,000 monthly prize pool
Ready for the live challenge? Join the next global round now.
*Terms apply. Skill-based competition.
Related Questions
Browse Nature & Animals →- Which consequence results when magnetic declination on migratory maps is uncalibrated?
- Which outcome occurs when nitrogen-fixing bacteria lacks molybdate?
- Which navigational failure occurs where strong localized magnetic anomalies distort animal migratory maps?
- Which photosynthetic inefficiency arises when stomatal closure limits?
- Which outcome is maximized by concurrent flow in bird respiratory system?
- Which consequence results when a kestrel relies primarily on thermals?
