Just like us and other living creatures on the earth, plants also need air to survive. While we, the human beings, need air only to breathe in, the plants need it for making their food as well. During the day and night time, plants inhale oxygen for survival. They absorb oxygen through pores found on undersides of the leaves. The oxygen spreads into the live cells of plants and makes them breathe. Carbon dioxide also seeps out through these pores.
Along with 24/7 requirement of oxygen, plants also need carbon dioxide during the day for making their food. In the presence of sunlight, the chlorophyll in leaves makes food with the help of water in the soil and carbon dioxide in the air. This process is known as photosynthesis. For photosynthesis, plants also inhale carbon dioxide through the same pores. So, plants need air for two reasons – respiration and photosynthesis.
In fact, plants are the nature’s greatest recycling agents. While all living creatures, animals and plants exhale carbon dioxide as a waste product of respiration, plants take up it during day time for making their food. During this process of making food or photosynthesis, plants convert carbon dioxide and water into oxygen.
Besides, plants do not need as much oxygen as animals or human beings, because they are stationery and they have different metabolic needs. This way, the earth never runs out of oxygen because plants continuously keep converting carbon dioxide into oxygen and keep seeping carbon dioxide for photosynthesis.