When we stop breathing, the process of respiration ceases because the body no longer has access to oxygen, a crucial element of life. Breathing is defined as the process of respiration, when air is brought into the lungs. Respiration involves two different processes--internal and external respiration. When you exhale, carbon dioxide is released into the atmosphere. Internal respiration refers to the swapping of oxygen and carbon dioxide between the cells of your body, and ultimately your blood.
Significance
The significance of breathing and the exchange of oxygen and carbon dioxide is the foundation of life. Energy comes from the foods we eat, but the energy must be released from the foods before we can use it. Respiration includes the process that frees the energy. The respiration equation states that glucose plus oxygen produces carbon dioxide plus water plus energy. A chemical reaction in your cells produces energy. When glucose and oxygen come together to produce energy, the chemical process releases carbon dioxide and water as waste.
Breathing In
Breathing allows air to travel through the trachea, into the bronchi, then into the alveoli, or tiny sacs in the lungs. Oxygen, a component of air, passes through the walls of the alveoli into your blood. The freshly oxygenated blood leaves your lungs through the pulmonary veins and travels to the left side of your heart. From there, the blood is pumped through the aorta to the cells throughout your body.
Breathing Out
Oxygen and nutrients such as glucose pass through the walls of the capillaries into the body's tissues. Glucose is broken down to release energy, which also produces carbon dioxide and water. Carbon dioxide dissolves in the blood--which flows to the right side of the heart, then back to the lungs through the pulmonary arteries. Most of the carbon dioxide leaves the blood through the alveoli, and ultimately your body, as you breathe out. The remaining carbon dioxide is released, along with water, when you urinate.
Deficiency
When your breathing is impaired as the result of an injury or lung disease, an oxygen deficiency can occur. A reduced oxygen level in arterial blood is called hypoxemia. Hypoxia involves a reduction in the oxygen supply to the tissues. Anoxia involves the complete absence of oxygen in the blood going to tissues, resulting in cell death if not immediately corrected.
Compliance and Resistance
How easily you breathe depends on two things: compliance and resistance. Compliance allows your lungs to increase in volume. The greater the compliance, the less work it takes to expand your lungs. Compliance essentially is the elasticity of your lungs to stretch and return to normal. Resistance refers to how easily air flows into and out of your lungs. The greater the resistance, the more work it takes to breathe in and breathe out. Lung disease can affect the compliance and resistance of the lungs.
