What happen to the level of carbon dioxide gas when the plants is in darkness why do this happen?

When plants are in darkness, the level of carbon dioxide (CO2) in their surroundings typically increases. This occurs because photosynthesis, the process by which plants absorb CO2 and release oxygen, ceases in the absence of light. Instead, plants continue to respire, consuming oxygen and releasing CO2 as a byproduct. Consequently, without the balancing effect of photosynthesis, CO2 levels rise during periods of darkness.