Why Is Oxygen So Essential for Life?

Oxygen makes up about 21% of Earth’s atmosphere, giving us the air we breathe.
Cells use oxygen in respiration to release energy from food.
Hemoglobin in red blood cells carries oxygen to every corner of your body.
Oxygen’s high reactivity lets it form bonds with many other elements.
Water, vital for life, is made of hydrogen and oxygen (H₂O).
Ozone, a form of oxygen, shields Earth from harmful ultraviolet rays.
Oxygen fuels combustion, making fire possible.
Plants and algae constantly replenish oxygen through photosynthesis.
Without oxygen, complex multicellular life like animals and humans couldn’t survive.
From your lungs to the stars, oxygen is woven into the chemistry of life and the universe.