Because it has the ability to get light, photosynthesis would happen. Since it is in an airtight jar, it will use all the CO2 in the jar until all the CO2 is gone and there is only Oxygen left. Photosynthesis's rate will decrease rapidly. After that, the plant will have no more energy since there is no CO2 to allow it to keep with photosynthesis, so it would die off.
Plant may die after several weeks due to non availability of CO2
Explanation:
When a plant is plotted in a covered polythene , it is sure that it has limited or no supply of air.
Thus , a plant will photosynthesis till the there is air in the air tight jar. Once the air get consumed in the jar, no CO2 will be available to the plant for carrying out the photo chemical reaction of photosynthesis process.
Hence, after a few days the plant may start decaying and it may die after several weeks.
