Question

why do plants won't take oxygen present in the water?

Answer 1

Plants release oxygen during photosynthesis. But still, they also need oxygen for respiration. There are certain cells in the plant which are similar to animal cells but are equipped for the process of respiration. They take in oxygen and aid in the process of oxygen. Plants generally take in water through the roots during the process of which even oxygen is split from the water that is consumed! Only when there is insufficient water in the soil, plants take oxygen from the atmosphere. Fishes and other aquatic animals cannot split oxygen from water but green plants and certain bacteria actually can! In certain plants like Avicenna the roots don't get enough oxygen from the soil because of salty water and that's why they have respiratory roots which are above the soil.