In this scenario, the most likely cause of the plant's death would be a lack of carbon dioxide.
Here's the reasoning:
- Plants need carbon dioxide for photosynthesis, the process they use to convert light energy into chemical energy (sugars). In a sealed environment, after the plant uses up the available carbon dioxide for photosynthesis, it will struggle to perform this essential process.
While a lack of light or oxygen could also lead to problems, in this closed system, if the plant is initially receiving light and can produce oxygen, it would still be able to produce sugars until the carbon dioxide runs out. So, a lack of carbon dioxide would be the most critical factor leading to the plant's death over time.