Breathing

Breathing is the process that allows living things, such as humans and animals, to take in oxygen and release carbon dioxide. It is something we do all the time, often without thinking. Every breath we take keeps our body working by bringing in fresh oxygen and removing waste gases. Without breathing, humans can only live for a few minutes because cells in the body need oxygen to make energy.

When a person breathes in, or inhales, air enters through the nose or mouth and travels down the windpipe into the lungs. Inside the lungs are millions of tiny air sacs called alveoli. These air sacs pass oxygen into the blood and take away carbon dioxide. When a person breathes out, or exhales, this carbon dioxide leaves the body. The constant exchange of gases keeps the blood clean and full of oxygen.

The main muscle that helps us breathe is called the diaphragm. It is a large, flat muscle just below the lungs. When the diaphragm moves down, the chest expands and air flows into the lungs. When it moves up, the lungs push air out. The ribs and other small muscles around the chest also help by making space for the lungs to grow and shrink as we breathe.

Breathing is not the same for all living things. fish, for example, get oxygen from water using their gills instead of lungs. Insects breathe through tiny holes on their bodies called spiracles. Plants also “breathe,” but in a different way—they take in carbon dioxide and release oxygen during photosynthesis in daylight, and do the opposite at night.

Healthy breathing is important for life and energy. When we run or exercise, our muscles need more oxygen, so we breathe faster. When we rest or sleep, our breathing slows down. People can train to control their breathing through deep breathing exercises or sports. Breathing fresh, clean air and keeping lungs healthy by avoiding smoke or pollution are key parts of good health.

Breathing connects all life on earth. Animals, plants, and humans all depend on the same cycle of gases in the air. oxygen supports life, and carbon dioxide helps plants grow. This shared system shows how all living things are linked by something as simple and natural as a single breath.