CO₂ as Limiting Factor in Photosynthesis — NEET Biology
📚 Practice ConceptCarbon dioxide is the major limiting factor for photosynthesis. The concentration of CO₂ is very low in the atmosphere (between 0.03 and 0.04 per cent). Increase in concentration upto 0.05 per cent can cause an increase in CO₂ fixation rates; beyond this the levels can become damaging over longer periods.
Assertion (A): Carbon dioxide is abundant in the atmosphere for photosynthesis. Reason (R): The concentration of CO2 in the atmosphere is between 0.03 and 0.04 per cent.
View solution & NCERT explanation
Correct answer: D — If the assertion is false but the reason is true.
NCERT states “The concentration of CO2 is very low in the atmosphere (between 0.03 and 0.04 per cent)” - the Assertion contradicts this by claiming CO2 is abundant (false). The Reason is exactly true from NCERT. Students might think CO2 is abundant since it’s essential for photosynthesis, making the false Assertion plausible.
What does NCERT say about Carbon dioxide major limiting?
Has this concept appeared in NEET?
Which chapter is this from?
Through deep analysis of NEET and NTA, 88 of 90 questions from the NEET 2026 paper were matched straight from the MedicNEET Biology question bank.
88/90MedicNEET's Biology question bank is built from the same NCERT lines NTA picks repeatedly. Not random MCQs — questions crafted exactly like NTA crafts them.