Difference Between Right and Left Lung

Introduction

Breathing is the natural process that involves the inspiration or intake of oxygen and the expiration or removal of carbon dioxide. This process is possible due to the respiratory system that involves the nostrils, pharynx, windpipe or trachea, bronchi and lungs. The trachea further bifurcates to form the right and the left lung. Its contraction and relaxation result in the intake and expel of the air.

Right lung

The right lung is shorter and wider as compared to the left lung and both perform the function of breathing.

Location of the right lung

The right lung is present in the right hemithorax region i.e. on the right side of the heart and mediastinum.

Structure of the right lung

The right lung comprises three lobes i.e the right upper lobe (RUL), the right middle lobe (RML) and the right lower lobe (RLL) and all these lobes are divided by two interlobular fissures. One of the fissures divides the right lower lobe from the middle and upper one and it closely resembles the fissure of the left lung and it is called a horizontal fissure. The other fissure divides the right upper lobe from the middle one and it is called an oblique fissure. The right lung comprises ten segments of which three segments are present in the right upper lobe i.e the apical, anterior and posterior and two segments are present in the right middle lobe i.e the medial and lateral and the remaining five are present in the right lower lobe i.e the superior, medial, anterior, lateral and posterior.

Left lung

The left lung is narrow and oblong and both lungs perform the process of breathing.

Location of the left lung

The left lung is present in the left hemithorax region i.e on the left side of the heart and mediastinum.

Structure of the left lung

The left lung comprises two lobes i.e the left upper lobe (LUL) and the left lower lobe (LLL). There is only one fissure present in the left lung and it is called the oblique fissure that divides the left upper and left lower lobe. There are eight to nine segments present in the left lung. Within the left upper lobe, there are 4 segments i.e the anterior, apicoposterior, inferior and superior lingula. The remaining 4 to 5 segments are present in the left lower lobe i.e the lateral, anteromedial, superior and posterior.

Images coming soon

Similarities between left and right lungs

• The major similarity between the left and right lungs is that they both perform the function of breathing.

• The alveoli of both the left and right lungs perform the function of respiration in which the carbon dioxide is exchanged with oxygen and is transported to the body parts via the bloodstream.

• Both of them are guarded by a sack of tissue called the pleura.

• Both the lungs are lobular in structure.

• The left and right lungs share a common windpipe or trachea.

Differences between left and right lung

	Right lung	Left lung
Structure	The right lung is short and wide in a structure.	The left lung is narrow and oblong in structure.
Position	The right lung is present in the right hemithorax region.	The left lung is present in the right hemithorax region.
Weight	The right lung is heavier than the left lung and weighs about 700 gms.	The left lung is lighter than the right lung and weighs about 650 gms.
Lobes	The right lung comprises three lobes i.e the upper, middle and lower.	The left lung comprises two lobes i.e the upper and lower.
No. of fissure	There are two fissures in the right lobe i.e the oblique and horizontal.	There is only one fissure in the left lobe i.e the oblique.
No. of bronchus	The bronchus is a structure that arises from the division of the trachea and in the right lung, there are two bronchi.	There is a single bronchus in the left lung.

Conclusion

Lungs are spongy structures that help in the process of breathing. The lungs are divided into two parts i.e the left and the right lung. The right lung is short and wide while the left is narrow and oblong. The right lung has three lobes i.e the upper, middle and lower lobes and is located on the right side of the heart and mediastinum. The left lung comprises two lobes i.e the upper and lower lobes and is located at the left side of the heart and mediastinum. These lobes are divided by inter-lobular fissures. Both the left and right lungs are segmented. They share some similarities like both perform the function of breathing or respiration, are lobular, etc. The left and lungs can be differentiated based on their location, structure, weight, no. of fissures, lobes, etc.

FAQs

Q1. Write the sequence of the respiratory system.

Ans. The respiratory system provides a tract for air and consists of;
Nostrils → Nasal cavity → Pharynx → Larynx → Trachea → Bronchi → Bronchioles → Air sacs or alveoli.

Q2. What is the mediastinum and where lungs are located?

Ans. The mediastinum is a region that provides space for vital organs like the heart, trachea, great vessels and essential nerves. The lungs are present on either side of the mediastinum i.e on the right and left.

Q3. What is hilum?

Ans. Hilum or root is a depressed structure at the centre of the lung and is located anteriorly at the 5th to 7th thoracic vertebrae. It is the place at which various structures enter and exit from the lung. It is guarded by a pleural layer and contains bronchi and pulmonary vasculature along with lymphatic nodes, bronchial vessels, etc.

Q4. Where does the exchange of gases take place?

Ans. Alveoli are considered the functional unit of the lungs that provide surface area for exchanging gases like carbon dioxide and oxygen.

Q5. Explain the blood system present between the lungs and heart.

Ans. The pulmonary artery from the right ventricle of the heart is responsible to carry deoxygenated blood toward the lungs. The pulmonary artery then expands along the branches of the bronchial tree and branches off into capillaries. The exchange of carbon dioxide from the blood with oxygen is carried out between the alveoli and the capillaries that contain deoxygenated or carbon dioxide-rich blood. The oxygen-rich blood is collected from the alveolar capillaries by the pulmonary vein. Then the oxygen-rich or oxygenated blood is taken up to the left atria and further, it is pumped throughout the body tissues.

Q6. Name some diseases associated with the lungs of the respiratory system.

Ans. Diseases of the lungs can be divided into the following −

• Airway diseases- chronic obstructive pulmonary disease, asthma, etc.
• Lung tissue diseases- Sarcoidosis, pulmonary fibrosis.

• Lung circulation diseases- Pulmonary hypertension.

  Lung diseases are usually a combination of the above diseases. Lung collapse, lung cancer, infections like pneumonia, pulmonary edema, pulmonary embolus, bronchitis, etc. are a few diseases.