Question

Plants are removed from patient's room during night because

• A. They consume $O_2$ at night.
• B. They release $C{O}_2$ at night.
• C. They produce $C{O}_2$ all the time but release $O_2$ only during day.
• D. They do not photosynthesize at night but they increase $C{O}_2$ concentration at night.

Answer 1

Answer: (D)

They do not photosynthesize at night but they increase $C{O}_2$ concentration at night.

A) Plants take in oxygen at night to release energy from the sugars formed during the day.

B) Plants release carbon dioxide at night as a byproduct of the breakdown of sugars for energy.

C) Plants absorb carbon dioxide during the day and produce it at night.
D) Plants are removed from patient's rooms at night because they may reduce the oxygen concentration of the air. Respiration uses oxygen to release energy from the stored sugar and produces carbon dioxide as a byproduct, increasing its concentration which is harmful for the patient.
So the correct answer is 'They do not photosynthesise but release CO2 and increase its concentration at night'.