Although terms like breathing and respiration have often been used interchangeably as being the same thing, there are however, many differences between the two processes. While breathing is from without, or external, respiration takes place inside the body, at an internal or cellular level.
When a person breathes, it is a voluntary action, as he/she can control how they take a breath or choose to hold it (as in snorkeling). Breathing can be slow or fast; shallow or deep; rhythmic breathing as in yoga or Lamaze breathing as a childbirth technique. On the other hand, respiration is strictly involuntary (a reflex); a mechanical process which involves taking oxygen through breathing, and converting this chemical energy into other forms of energy. Because respiration is involuntary, it cannot be controlled like breathing.
Human Respiratory System
The respiratory system includes the nose, pharynx (throat), larynx (voice box), trachea (windpipe), bronchi, bronchioles and alveoli that comprise the lungs.
The nose serves to warm, moisten, and filter the incoming air that is breathed. Little hairs in nasal passages prevent foreign particles from entering. The mucus membrane and mucus that form in the sinuses help trap dust, bacteria and other particles in the air.
The pharynx or the throat is where air comes in, and the larynx or voice box is where air goes out. The larynx goes right into the trachea or windpipe, also covered by a mucus membrane and hairlike projections called cilia. The purpose of the trachea is to move mucus and foreign particles out via the pharynx. Since smoke prevents the cilia from moving and increases the amount of mucus in air passages, it might be prudent to stop smoking to improve air quality being breathed in.
At this point, the trachea divides into two cartilage-ringed tubes called bronchi, located in the center of the chest. The bronchi, in turn lead into the lungs, where they spread out like limbs of a tree into smaller tubes called bronchioles. These bronchioles end in a tiny chamber filled with cup-shaped cavities called aveoli. These structures are very thin, moist, and surrounded by capillaries. This is where the exchange of oxygen (O2) and carbon dioxide (CO2) take place.
Breathing is a constant process which involves taking oxygen into the lungs, and expelling carbon dioxide after respiration takes place. It is comprised of two stages: movement of air in and out of the lungs, called “ventilation”; the second stage involves an exchange of gases, mainly oxygen into the lungs and carbon dioxide out the lungs. When a person breathes, air goes through the entire respiratory system until it reaches an aveolus. Then the process of respiration begins.
This is a chemical function that takes place within the cells. When oxygen enters the lungs, blood in the lungs carries the oxygen through the pulmonary arteries, arterioles, then to aveoli capillaries. This oxygen is broken down through a catabolic process, where energy molecules are released and utilized by cells. At the same time, carbon dioxide and water are released back into the bloodstream or cells, to be eliminated; forming an exchange of gases through reverse actions previously mentioned.
Since the differences outlined above between breathing and respiration are relatively straightforward, one now knows how to use these words in their proper context and correctly.