Mechanism breathing: inhale and exhale:
Breathing is the process of taking in oxygen and releasing carbon dioxide. It is essential for life and is controlled by the autonomic nervous system.
Inhalation:
Inhalation is the process of taking air into the lungs. It is powered by the diaphragm, a muscle that separates the chest cavity from the abdominal cavity. When the diaphragm contracts, it moves down, which increases the volume of the chest cavity. This creates a negative pressure in the chest cavity, which draws air into the lungs.
The air enters the lungs through the trachea, or windpipe, which divides into two bronchi, one for each lung. The bronchi then subdivide into smaller and smaller bronchioles, which eventually terminate in tiny sacs called alveoli.
The alveoli are surrounded by a network of blood vessels called capillaries. As air passes through the alveoli, oxygen diffuses from the air into the blood and carbon dioxide diffuses from the blood into the air. The oxygenated blood then travels to the heart and is pumped to the rest of the body.
Exhalation:
Exhalation is the process of releasing air from the lungs. It is powered by the relaxation of the diaphragm and the elastic recoil of the lungs. When the diaphragm relaxes, it moves up, which decreases the volume of the chest cavity. This creates a positive pressure in the chest cavity, which pushes air out of the lungs.
The air leaves the lungs through the same bronchi and trachea that it entered through. As the air passes through the airways, it picks up water vapor, which is why we exhale water vapor.
The rate and depth of breathing can vary depending on a number of factors, including activity level, fitness level, and altitude. When we are at rest, we breathe about 12 to 16 times per minute. When we are exercising, our breathing rate and depth increase to meet the increased demand for oxygen.
Breathing is a complex process that is essential for life. It is controlled by the autonomic nervous system, but we can also control our breathing voluntarily to some extent. For example, we can hold our breath or breathe more deeply if we need to.
Here are some additional facts about breathing:
- The average adult breathes about 12 to 16 times per minute.
- The average adult takes in about 5 to 8 liters of air per minute at rest.
- The average adult exhales about 5 to 8 liters of carbon dioxide per minute at rest.
- The lungs contain about 300 million alveoli.
- The surface area of the alveoli is about the size of a tennis court.
- The blood travels through the capillaries in the lungs about four times per minute.
- The blood cells in the capillaries are about 7 to 8 micrometers in diameter, while the capillaries are about 5 to 7 micrometers in diameter. This allows the oxygen and carbon dioxide to diffuse easily between the blood and the air.
