Respiratory System: Functions, Facts, Organs & Diseases

We all know that we can live without food and water for some days, but survival without air is not possible at all. We continuously breathe in and breathe out air through our noses.

What happens to the air that goes inside?

What systems are working inside that distribute this air?

The system that facilitates this process of inhalation and exhalation of air is the respiratory system. And the process through which we inhale and exhale is breathing.

In this article, we will discuss the anatomy of the respiratory system, its functioning, its related organs, and the diseases associated with it.

What Is the Respiratory System?

It is a vast network of respiratory organs, tissues, and muscles that function together to help you breathe. When you breathe, you inhale oxygen and transfer it to every cell of the body. On the contrary, when you exhale, you throw carbon dioxide out of the body, which is generated as waste in the body cells.

Physiology of Respiratory System

Before understanding the organs in the respiratory system, we will first look at the respiratory system structure. If you look at the diagram of the human respiratory system, you will find that it is divided into two parts. These are the upper respiratory tract and the lower respiratory tract. Let’s get to know the different parts of these two tracts.

The Upper Respiratory Tract:

It consists of four parts: the nose and the nasal cavity; the sinuses; the pharynx; and the larynx.

The Nose and the Nasal Cavity:

Do you know what’s wonderful about the nose?

It’s the only part of any system (out of so many) that is present on the exterior portion of the body.

The two exterior openings that you see on your nose are nostrils. This is the path through which air enters your body. The two nostrils lead into the nasal cavity, and a cartilaginous structure known as the nasal septum divides it into two.

The nasal cavity has hair and mucus on the inside wall, which makes the coming air cleaner, more humid, and more moisturized. The nasal hair prevents dust, dirt, and other contaminants from reaching inside the lungs.

The Sinuses:

Sinuses are hollow air spaces present around the nose behind the front of the skull. These are present in four pairs and regulate the humidity and temperature of the inhaled air.

It’s the sinuses that give you the tone in your voice. Though present since birth, it grows to its full size by the age of 20 years.

The Pharynx:

You may know it commonly as throat. It is a funnel-shaped muscular tube starting from your mouth and connecting the nasal cavity to the trachea or the windpipe through the larynx. Additionally, it also connects your oral cavity and nasal cavity to the larynx and food pipe.

The pharynx is the connecting link and transfers air from the nasal cavity to the larynx. At the same time, food also passes from the oral cavity to the esophagus via the pharynx. A part of the pharynx called the nasopharynx has an epiglottis that acts as a switch between the larynx and the esophagus. It prevents air from entering the esophagus.

The Larynx:

It is a small tube (approx. 2 inches) with 9 cartilages that connect the trachea and pharynx. It serves two functions. Firstly, it acts as a canal to let air go to the lungs, and secondly, it has a voice box with vocal cords. It’s the voice box that gives us the ability to speak. While swallowing food, it's the epiglottis that prevents the food from entering the larynx by covering it.

Did you ever cough when you tried to speak while eating?

You must have. This is because when you speak along with swallowing food, your epiglottis becomes confused. It keeps the esophagus open to allow food entry, and at the same time, it opens the larynx to allow you to speak. In such a case, some foot particles enter the larynx, and you start coughing.

The Lower Respiratory Tract:

The Trachea:

Starting from the larynx, the trachea moves down the neck to the breastbone and splits into two branches called bronchi, entering into two lungs. Also known as the windpipe, the trachea has C-shaped cartilaginous structures in the inner walls. This ring-like structure maintains stiffness and also gives it the required flexibility.

Bronchi:

As the trachea splits into two bronchi, each bronchus enters each lung individually. The bronchi leads to several other secondary branches known as bronchioles. These bronchioles finally form small sac-like structures at their tips called alveoli. These are single-celled structures with thin walls. You can get a clear picture by referring to the diagram of the respiratory system. The exchange of air from the lungs to the body and vice versa occurs through these alveoli only.

The Lungs:

Located in the chest’s thoracic cavity, these spongy organs are the main parts of the respiratory system, allowing the exchange of gasses. The anatomy of both lungs is the same, but the size of the right lung is slightly larger than the left lung.

Diaphragm:

A dome-shaped muscle located towards the lower side of the lungs is the diaphragm. Separating the chest from the abdomen, these muscles aid in respiration by contracting and relaxing. The diaphragm pulls itself down when you inhale air so that the lungs can expand to accommodate air. On the contrary, it pushes upwards when you breathe out to let carbon dioxide out of the body.

Functions of the Respiratory System

As already said, your body needs energy, which it gets from breaking down glucose molecules. For this, it requires oxygen. While creating energy, the cells create carbon dioxide as a waste product. It is essential to throw this carbon dioxide out of the body; otherwise, it can affect your health. This gaseous exchange in the respiratory system works in close connection with the circulatory system to execute this exchange of gasses.

The function of the lungs in the respiratory system is very crucial. When the oxygen reaches the lungs, it diffuses into the pulmonary capillaries from the alveoli. From there, it binds with hemoglobin and reaches each part of the body through blood. Similarly, the impure blood that collects carbon dioxide from individual cells gets diffused into alveoli and expelled when you breathe out.

Other Functions:

• Ability to Speak: While speaking, the larynx muscles move the cartilage. These moving cartilages exert a force on the vocal cords, bringing them together. Now, when you exhale air, it vibrates the vocal cords while passing through them, creating sound.

• Sense of Smell: When you inhale air, the chemicals in the air bind to the nervous system receptors present in the cilia. These receptors send signals to the olfactory bulbs through the brain. As a result, you can identify the smell or the fragrance present in the air.

Some Interesting Facts About the Respiratory System

• Human lungs have so much capacity that they can retain up to 1 liter of air even after we exhale completely.

• The air inhaled has around 21% oxygen, but our body uses only 5% of it.

• Surprisingly, your sneeze can travel up to 100 miles per hour, throwing away all the dirt, dust, air, and bacteria outside.

• In one pair of human lungs, almost 300 million alveoli are present.

• Your lungs may become the size of a tennis court if they are unfolded and expanded to their full capacity.

Respiratory System Diseases

Your respiratory system may be disrupted by the germs, dirt, dust, and irritants that enter your body along with the air. These particles can affect the muscles, tissues, and organs of the system, leading to infections. Apart from this, some injuries or genetic reasons can also lead to respiratory issues.

Some of the common respiratory conditions are:

Allergic rhinitis: this is the allergic reaction that happens in response to dust, tree pollen, and other allergens that affect your nasal passage.

Chronic Obstructive Pulmonary Disease (COPD)

COPD occurs when heavy smoking leads to inflamed airways. As a result, it becomes difficult to breathe, and you may feel breathlessness, chest infections, and a continuous cough.

Upper and Lower Respiratory Tract Infections

These include flu and other common colds:

Asthma:

It is a chronic inflammatory condition affecting your airways. Symptoms include tightness in the chest, regular coughing, and shortness of breath.

Acid-base Imbalances:

When you either exhale too much or too little carbon dioxide, it leads to an acid-base imbalance in your blood.

Blockages:

Hindrances in the path of air anywhere in the respiratory tract. The blockages can be due to some foreign particle, some benign growth, or some cancerous tumor.

Inflammation:

Inflammation in different parts of the respiratory system leads to different conditions. for instance-

• Inflammation in the Airways: Inflamed airways lead to bronchitis, releasing too much mucus that causes wheezing, coughing, and fatigue. Bronchitis is either acute or chronic. Chronic bronchitis is a case of COPD. It may be recommended that you drink plenty of water to melt down mucus in the airways.

• Inflammation in Alveoli: It leads to pneumonia and may occur due to infection in alveoli caused by bacteria, fungi, and viruses. You may have a high temperature, chest pain, cough, and breathing difficulty. Sometimes, pneumonia becomes serious, requiring urgent and continuous medical care.

• Inflammation in the Sinuses: Infections in the sinuses lead to sinusitis. You may feel facial pain, a runny nose, and a headache. For relief, you can take nasal sprays, decongestants, and pain relievers.

Lung Cancer:

The cancer that happens in the lungs is lung cancer. However, the severity of cancer depends on its location, i.e., whether it is in the alveoli or airways. Symptoms include chest pain, shortness of breath, wheezing, sudden weight loss, and coughing with blood. This is a dangerous type of cancer, as people do not get any symptoms until it reaches its advanced stage.

Treatments for Respiratory Illnesses

One of the most common treatment options for major respiratory illnesses is inhaled medication. Your healthcare provider may suggest inhalers or nebulizers from some reputed brands, like OMRON. These nebulizers convert corticosteroids, bronchodilators, and other such medications from liquid form to mist form. As a result, these medications can reach your airways and lungs easily and quickly, offering prompt relief of symptoms.

The best part of nebulizers is that they are suitable for all age groups and are user-friendly. These nebulisers help manage symptoms of asthma, cystic fibrosis, COPD management, pneumonia, and severe allergies.

Other than inhalers, you can also take oral medications such as antibiotics, antihistamines, antifungals, and antivirals.

Some respiratory conditions may also cause a dip in the oxygen level in your blood. If you are going through any such condition, keep an eye on your oxygen level with an oximeter.

For tumors and blockages, you may need to undergo surgery.

In some rare cases of lung cancer, a lung transplant is the only treatment option left.

Some Tips for a Healthy Respiratory System

Although you cannot avoid some respiratory illnesses, taking some precautions can surely help you avoid common infections.

• Smoking cigarettes and vaping liquids can lead to several conditions and diseases in the airways. So, avoid them.

• Avoid exposure to pollutants like chemicals, radioactive gas, or harmful smoke. Try to wear masks if you are required to work in such an environment.

• Always drink plenty of water, as it keeps your mucus thin and makes it easier to flush out.

• Do regular exercise, as it keeps your lung muscles strong and healthy. Easy and deep breathing exercises can also help.

• Wash your hands regularly to avoid any germs and dirt entering your nasal cavity through your hands.

• Get your children and yourself vaccinated against respiratory conditions like the flu and pneumonia.

• Go for regular health checkups to identify any possible respiratory conditions.

Conclusion

The human respiratory system brings in the source of energy and expels the waste out of the body. Thus, it is essential to maintain the right functionality of this system or be ready to face health issues.

Do not ignore any kind of cough, sneezing, or pain in your respiratory tract. Consult your healthcare provider if your cough won’t go away in a few days. Most respiratory conditions lead to shortness of breath, so always keep your inhalers or nebulizers with you. This will help in emergencies.

Also, make sure that you invest in a high-quality product. Try OMRON’s nebuliser or oximeter for the best results.