The NCERT chapter names three respiratory disorders you must know for NEET: Asthma (difficulty in breathing with wheezing, due to inflammation of the bronchi and bronchioles), Emphysema (a chronic disorder where the alveolar walls are damaged so the respiratory surface is decreased, mainly caused by cigarette smoking), and Occupational disorders like silicosis (long dust exposure in grinding/stone-breaking causes fibrosis). Memory hook: Asthma hits the AIRWAYS (bronchi/bronchioles), Emphysema destroys the ALVEOLI, and Occupational disorders come from DUST at work.
Three NEET respiratory disorders: asthma (airways/bronchioles, allergens), emphysema (alveoli damaged, smoking), and occupational silicosis (dust, fibrosis).
Your doubts, answered
Which part of the airway does asthma affect - bronchi or alveoli?
Asthma affects the bronchi and bronchioles, not the alveoli. NCERT defines asthma as difficulty in breathing that causes wheezing due to inflammation of the bronchi and bronchioles. The alveoli are affected in emphysema, not asthma. Students lose marks by mixing these two.
What exactly does emphysema damage, and why does it matter?
Emphysema damages the alveolar walls. Because the alveoli are the surface where gas exchange happens, damaging their walls decreases the total respiratory (exchange) surface. Less surface means less oxygen can diffuse into blood. NCERT names cigarette smoking as one of the major causes.
Which respiratory disorder is mainly caused by cigarette smoking?
Emphysema. NCERT states plainly that one of the major causes of emphysema is cigarette smoking. Asthma is triggered by allergens and pollutants (an allergic reaction), not directly by smoking, so do not pick asthma for the 'smoking' question.
What are occupational respiratory disorders and give an example?
Occupational respiratory disorders occur from long exposure to harmful substances at work. In industries with grinding or stone-breaking, so much dust is produced that the body's defence cannot cope; long exposure causes inflammation, fibrosis (proliferation of fibrous tissue) and serious lung damage. Silicosis is the classic NCERT example; workers should wear protective masks.
Why does wheezing happen in asthma?
Wheezing is the whistling sound of air passing through narrowed airways. In asthma the bronchi and bronchioles are inflamed and narrowed, often triggered by an allergic (hypersensitivity) reaction involving mast cells in the lungs. Rising air-borne allergens and pollutants in cities increase asthma cases.
⚠️ The NEET trap ✗ Asthma damages the alveolar walls and decreases respiratory surface. ✓ Asthma = inflammation of the bronchi and bronchioles (airway problem). Emphysema = alveolar walls damaged, so respiratory surface is decreased. Keep 'airway' with asthma and 'alveoli' with emphysema. 🧠 The favourite trap: swapping the site of asthma and emphysema.
Real NEET questions
2019
Due to increasing air-borne allergens and pollutants, many people in urban areas are suffering from respiratory disorder causing wheezing due to
A · benign growth on mucous lining of nasal cavity
B · inflammation of bronchi and bronchioles ✓
C · proliferation of fibrous tissues and damage of the alveolar walls
D · reduction in the secretion of surfactants by pneumocytes
Solution: Wheezing triggered by allergens and pollutants is asthma, which NCERT defines as difficulty in breathing causing wheezing due to inflammation of the bronchi and bronchioles. Option (c) describes emphysema/fibrosis, not asthma.
2018
Which of the following options correctly represents the lung conditions in asthma and emphysema, respectively?
A · Increased respiratory surface; Inflammation of bronchioles
B · Increased number of bronchioles; Increased respiratory surface
C · Inflammation of bronchioles; Decreased respiratory surface ✓
D · Decreased respiratory surface; Inflammation of bronchioles
Solution: Asthma = inflammation of bronchi and bronchioles. Emphysema = alveolar walls damaged, so the respiratory surface is decreased. Hence asthma is inflammation of bronchioles and emphysema is decreased respiratory surface.
2018
Which of the following is an occupational respiratory disorder?
A · Botulism
B · Silicosis ✓
C · Anthracis
D · Emphysema
Solution: Silicosis is an occupational disorder from long dust exposure in grinding/stone-breaking industries, leading to fibrosis and lung damage. Botulism and anthrax are bacterial, and emphysema is chiefly caused by cigarette smoking, not dust at work.
Solved Breathing and Exchange of Gases NEET PYQs
Try the real previous-year questions from this chapter — each with the answer and a full solution.
How many respiratory disorders does NCERT cover for NEET?
Three groups: Asthma, Emphysema, and Occupational respiratory disorders (such as silicosis). Knowing the cause and site of each is enough to answer almost every NEET question from this section.
Is asthma caused by a bacterial infection?
No. Asthma is due to inflammation of the bronchi and bronchioles, usually from an allergic (hypersensitivity) reaction involving mast cells in the lungs, triggered by allergens and pollutants. It is not a bacterial infection.
What single fact separates asthma from emphysema?
The site. Asthma affects the airways (bronchi and bronchioles) with inflammation and wheezing. Emphysema affects the alveoli, damaging their walls and decreasing the respiratory surface. Emphysema is mainly caused by smoking.
Why should factory workers wear protective masks?
In industries with grinding or stone-breaking, heavy dust overwhelms the body's defence. Long exposure causes inflammation and fibrosis, leading to serious lung damage such as silicosis. Protective masks reduce dust inhalation and prevent occupational lung disease.
