NEET Practice Questions (MCQs) with Answers & Solutions

Pneumonia is an infection that inflames the air sacs in one or both lungs, which can fill with fluid. It is caused by bacteria, viruses, or fungi, and not by specific gases, chemicals, or suspended particulate matter in the air. Silicosis, asbestosis, and fibrosis are all lung conditions caused by inhalation of harmful substances.

Crocodiles are reptiles, and they respire through lungs. Fish respire through gills, cockroaches through tracheae, and earthworms through their skin. Understanding the respiratory systems of different organisms is crucial for NEET biology.

The human lungs are located in the thoracic cavity, which is the chamber of the body of vertebrates that is protected by the thoracic wall (rib cage and associated muscles). This is a fundamental concept in human anatomy for NEET students.

The left lung is slightly smaller than the right lung to accommodate the space for the heart. The heart is located towards the left side of the chest, necessitating the left lung to be slightly smaller in size. This anatomical arrangement allows the heart to fit snugly between the lungs.

Silicosis is a lung disorder related to profession, particularly affecting workers who inhale silica dust over long periods. This condition is common in occupations such as mining, quarrying, and sandblasting. Silica dust causes inflammation and scarring in the lungs, leading to difficulty in breathing.

Bronchitis can be caused by an initial viral infection that is followed by a secondary bacterial infection. The viral infection damages the bronchial tubes, making them more susceptible to bacterial invasion. This dual infection process is why bronchitis often starts with a viral illness and then worsens due to bacterial involvement.

Lung cancer is characterized by the formation of masses of undifferentiated cells in the tracheal walls. These undifferentiated cells can form tumors that obstruct the airways, leading to issues with breathing and other respiratory functions.

The ventral respiratory center is responsible for exciting both inhalation and exhalation during rapid breathing. It plays a crucial role in regulating the rhythm and depth of breaths during situations that require increased respiratory effort.

During normal breathing, the ventral respiratory center does not play a significant role. It is more actively involved during forceful breathing, such as during exercise or stress, where it helps in controlling the intensity of respiratory efforts.

The full form of Hb is Haemoglobin. Haemoglobin is a protein in red blood cells that carries oxygen from the lungs to the rest of the body. It also returns carbon dioxide from the body to the lungs so it can be exhaled.