What is the Respiratory System?
The respiratory system comprises of all of those organs that are responsible for breathing or respiration. The functioning of the respiratory system is critical to your very existence, as the flow of air to the lungs and the expansion and contraction of the lungs is what supplies oxygen throughout your body, while removing carbon dioxide. Respiratory diseases and conditions that affect your ability to breathe can vary greatly in severity, with many conditions even being life threatening. It is not possible for the human body to function at its optimum levels if there is any reduction in the efficiency of respiratory function.
The respiratory system comprises of various organs and structures starting with the nose and mouth. As you inhale air, it travels through the mouth or nose, from where it makes its way through the windpipe or trachea. The trachea then divides into small tubes called bronchial tubes. These carry air to the lungs, where inhaled oxygen is absorbed into the blood by the red blood cells for supply throughout the body. The red blood cells also collect carbon dioxide and then deliver it to the lungs for exhalation.
What are the Causes of Respiratory Disorders?
Respiratory disorders, or more precisely respiratory symptoms, may not always be caused by a condition that develops in the respiratory tract itself. In addition to lung disease, or diseases that affect the other organs of the respiratory tract, symptoms may also surface on account of heart disease, injury or psychosomatic conditions. For example, anxiety and panic attacks, which are increasingly common psychological disorders, cause symptoms like breathlessness and rapid breathing. Heart failure can also cause severe respiratory symptoms, but the most common cause remains viral and bacterial infections of the respiratory tract like common cold, pneumonia and tuberculosis. Some conditions like asthma are caused by a problem in immune response in the presence of certain allergens.
Respiratory System Facts
All of us have experienced some kind of respiratory infection or disease at some point in our lives, more likely on multiple occasions. Despite the fact that we are so familiar with diseases of the respiratory tract, most people lack much knowledge about the respiratory system. Here are some respiratory system facts:
- Have you ever noticed condensation on a glass window pane when you exhale against it? This condensation occurs because the air you exhale contains a high level of humidity. In other words, you donít just exhale carbon dioxide, but also a lot of water vapor. You normally lose around 17.5 milliliters of water per hour simply through exhaling, an amount that goes up to 4 times higher when exercising!
- Do you pride yourself on being able to hold your breath for over a minute? There are some individuals who can hold their breath for as long as 20 minutes and even more, with the record being held by a Danish free diver at 22 minutes! While this may deflate your ego, donít trouble yourself too much about it. The average amount of time that a person can hold their breath is around 30 to 60 seconds.
- Contrary to popular belief, your lungs are not perfectly symmetrical. The left lung is actually slightly smaller than the right lung. It is because the left lung has what is called a cardiac notch to make room for the heart.
- Nasal hair is not exactly fashionable and most of us grimace at the site of untrimmed nasal hair, but tiny hairs that grow within the nasal cavity serve an important purpose. Referred to as cilia, these tiny hairs help to filter out dust and other particulate matter as you inhale air. During winter and in regions with a cold climate, they also help to warm the air as it passes through.
- The lungs are the only organ in the human body to have buoyancy! The lungs have tiny balloon-like sacs called alveoli that fill up with air each time you inhale. There are over 300 million of these little inflatable sacs in the lungs giving it natural buoyancy! Incidentally, the alveoli also help in the removal of carbon dioxide from the blood.
- Sneezing is a semi-involuntary mechanism for the removal of air from the lungs to overcome any kind of irritation to the air passages caused by any kind of irritants such as smoke, dust or animal fur and dander. Sneezing is often seen as amusing or fascinating, but whatís really remarkable is the speed at which the air is exhaled when you sneeze. If a miniature car could fit into your nasal passage and were to be exhaled with the air when you sneeze, it could even be doing a good 165km per hour as it made its exit!
- We already know that the lungs get their buoyancy from the millions of alveoli, which are balloon like sacs. Understanding how the alveoli work to supply your body with oxygen reveals another interesting fact. The thin walls of the alveoli are lined with minute blood vessels called capillaries. The blood in the capillaries absorb oxygen from the air, each time the alveoli fill with inhaled air. At the same time, the capillaries also deposit carbon dioxide in the alveoli, making what can be viewed as a gas exchange. If you isolate each of these capillaries from each of the 300 million alveoli and connect them end to end, they would reach a length of 1,600 kilometers, more than the distance from New Delhi to Mumbai!
- Breathing rates are not uniform in children, women and men. Women and children have faster breathing rates as compared to men, with newborns having the fastest breathing rate. On an average, most adults inhale and exhale around 12 to 15 times in a minute, but newborns have a breath rate that as much as 4 times higher with around 30 to 60 breaths per minute.
- Did you know that each time you yawn, your respiratory system is actually compensating for a shortage of oxygen in your body? Whenever your brain senses a shortage of oxygen, it signals your respiratory system causing you to yawn and take in a large amount of air.
- The alveoli in both lungs are so numerous that if they were to be spread out flat on the ground, they would cover an area near the size of a singles tennis court at 160 square meters!
- Each red blood cell contains 250 hemoglobin molecules, each carrying 4 oxygen molecules. It gets even more astounding when you learn that just one microliter or cubic millimeter of blood contains around 4 to 6 million red blood cells!
- There is a slight variation in the lung capacity or amount of air that can be held in the lungs between the genders, with males having slightly higher lung capacity as compared to women. On an average, the human lungs can hold around 4 to 6 liters of air.
- Breathing is not a conscious activity and itís an action regulated by the medulla oblongata in the brainstem.
- Contrary to popular belief, it is not falling oxygen levels that trigger inhalation as compared to rising carbon dioxide levels in the blood.