NEET Topic-wise & A
Topic 1: HUMAN RESPIRATORY SYSTEM
Model Questions
01. Select the correct sequence of different regions of human respiratory tract (air passage).
(1) Nostrils → nasal chamber → nasal passage → larynx → nasopharynx → trachea → bronchi → bronchioles → alveolar duct
(2) Nostrils → nasopharynx → nasal passage → nasal chamber → larynx → bronchi → trachea → bronchioles → alveolar duct
(3) Nostrils → nasal passage → nasal chamber → nasopharynx → larynx → trachea → bronchi → bronchioles → alveolar duct
(4) Nostrils → nasal passage → nasal chamber → trachea → larynx → nasopharynx → bronchi → bronchioles → alveolar duct
✅ (3) Nostrils → nasal passage → nasal chamber → nasopharynx → larynx → trachea → bronchi → bronchioles → alveolar duct
02. Trachea is a straight tube extending up to the mid-thoracic cavity, which divides at the level of
(1) 5th thoracic vertebra
(2) 2nd thoracic vertebra
(3) 7th thoracic vertebra
(4) 3rd thoracic vertebra
✅ (1) 5th thoracic vertebra
03. Which statement is completely true?
(1) During swallowing, glottis closes epiglottis to prevent entry of food into larynx.
(2) During swallowing, epiglottis closes glottis to prevent entry of food into pharynx.
(3) During swallowing, glottis closes epiglottis to prevent entry of food into pharynx.
(4) During swallowing, epiglottis closes glottis to prevent entry of food into larynx.
✅ (4) During swallowing, epiglottis closes glottis to prevent entry of food into larynx.
04. Which of the following is incorrect about human lungs?
(1) Situate in thoracic chamber and rest on diaphragm
(2) Right lung has 2 lobes and left lung has 3 lobes
(3) Lungs are covered by outer parietal pleura and inner visceral pleura
(4) The pleural fluid lubricates the surface of lungs and prevents friction between the membranes
✅ (2) Right lung has 2 lobes and left lung has 3 lobes
05. Structural and functional units of lungs are
(1) Bronchioles
(2) Bronchi
(3) Alveoli
(4) Capillaries
✅ (3) Alveoli
Topic 2: MECHANISM OF BREATHING (INSPIRATION & EXPIRATION)
NEET: Previous Years Questions
06. Match List I with List II. (NEET 2024)
Choose the correct answer from the options given below:
(1) A-II, B-IV, C-I, D-III
(2) A-III, B-II, C-IV, D-I
(3) A-II, B-I, C-IV, D-III
(4) A-I, B-III, C-II, D-IV
✅ (1) A-II, B-IV, C-I, D-III
07. Vital capacity of lung is ……………….
(1) IRV + ERV + TV + RV
(2) IRV + ERV + RV
(3) IRV + ERV + TV
(4) IRV + ERV (NEET 2023)
✅ (3) IRV + ERV + TV
08. Select the correct events that occur during inspiration. (NEET 2020)
(a) Contraction of diaphragm
(b) Contraction of external inter-costal muscles
(c) Pulmonary volume decreases
(d) Intra pulmonary pressure increases
(1) (a), (b) and (d)
(2) only (d)
(3) (a) and (b)
(4) (c) and (d)
✅ (3) (a) and (b)
09. Tidal Volume and Expiratory Reserve Volume of an athlete is 500 mL and 1000 mL respectively. What will be his Expiratory Capacity if the Residual Volume is 1200 mL? (NEET 2019)
(1) 1500 mL
(2) 1700 mL
(2) 2200 mL
(4) 2700 mL
✅ (1) 1500 mL
10. Match the items given in column I with those in column II and select the correct option given below:
i ii iii iv
(1) c b a d
(2) c a d b
(3) a d b c
(4) d c b a (NEET 2018)
✅ (2) c a d b
11. Lungs are made up of air-filled sacs, the alveoli. They do not collapse even after forceful expiration, because of
(1) inspiratory reserve volume
(2) tidal volume
(3) expiratory reserve volume
(4) residual volume (NEET 2017)
✅ (4) residual volume
12. Lungs do not collapse between breaths and some air always remains in the lungs which can never be expelled because
(1) there is a negative pressure in the lungs
(2) there is a negative intrapleural pressure pulling at the lung walls
(3) there is a positive intrapleural pressure
(4) pressure in the lungs is higher than the atmospheric pressure. (NEET-II 2016)
✅ (2) there is a negative intrapleural pressure pulling at the lung walls
Model Questions
13. Analyze the statements regarding the functions of conducting part of human respiratory system.
I. Transports the atmospheric air to the alveoli and cools down the air
II. Humidifies the air and brings the air to body temperature
III. Transports the atmospheric air to the alveoli and clears it from foreign particles
(1) I & II are correct
(2) II & III are correct
(3) Only III is correct
(4) I & III are correct
✅ (2) II & III are correct
14. Which does not take place during inhalation?
(1) Diaphragm contracts
(2) External intercostals muscles contract
(3) Thoracic volume in antero-posterior axis decreases
(4) Thoracic volume in dorso-ventral axis increases
✅ (3) Thoracic volume in antero-posterior axis decreases
15. Match the items in column I with column II and choose the correct option.
a b c d e
(1) 3 4 2 1 5
(2) 3 1 2 5 4
(3) 3 1 4 5 2
(4) 5 4 2 1 3
✅ (2) 3 1 2 5 4
16. Maximum amount of air one can renew in the respiratory system in a single respiration is called
(1) Tidal volume
(2) Total lung capacity
(3) Vital capacity
(4) Inspiratory reserve volume
✅ (3) Vital capacity
17. Tidal volume for a healthy man in an hour would be
(1) 360000 – 480000 ml
(2) 3600 – 4800 ml
(3) 480000 – 600000 ml
(4) 4800 – 6000 ml
✅ (1) 360000 – 480000 ml
18. Volume of air remaining in lungs after a forcible expiration is called
(1) TV
(2) FRC
(3) ERV
(4) RV
✅ (4) RV
19. After forceful inspiration, the amount of air that can be breathed out by maximum forced expiration is equal to
(1) IRV + RV + ERV
(2) IRV + TV + ERV
(3) IRV + ERV + TV + RV
(4) TV + RV + ERV
✅ (2) IRV + TV + ERV
Topic 3: GAS EXCHANGE
NEET: Previous Years Questions
20. The partial pressures (in mm Hg) of oxygen (O₂) and carbon dioxide (CO₂) at alveoli (the site of diffusion) are:
(1) pO₂ = 104 and pCO₂ = 40
(2) pO₂ = 40 and pCO₂ = 45
(3) pO₂ = 95 and pCO₂ = 40
(4) pO₂ = 159 and pCO₂ = 0.3 (NEET 2021)
✅ (1) pO₂ = 104 and pCO₂ = 40
21. The partial pressure of oxygen in the alveoli of the lungs is
(1) equal to that in the blood
(2) more than that in the blood
(3) less than that in the blood
(4) less than that of carbon dioxide (NEET-II 2016)
✅ (2) more than that in the blood
Model Questions
22. The factor which does not affect the rate of alveolar diffusion is
(1) Solubility of gases
(2) Thickness of membranes
(3) Pressure /Concentration gradients
(4) Reactivity of the gases
✅ (4) Reactivity of the gases
23. The figure given below shows a small part of human lung where exchange of gas takes place. In which one of the options given below, the one part A, B, C or D is correctly identified along with its function.
✅ (1) A – alveolar cavity: Main site of exchange of respiratory gases
24. The maximum affinity for haemoglobin is for
(1) CO₂
(2) CO
(3) Oxygen
(4) SO₂
✅ (2) CO
25. Which of the following statements are true/false?
i. The blood transports CO₂ comparatively easily because of its highest solubility.
ii. Approximately 8.9 % of CO₂ is transported being dissolved in the plasma of blood.
iii. The CO₂ produced by the tissues, diffuses passively into the blood stream and passes into red blood corpuscles and react with water to form H2CO₃.
iv. Oxyhaemoglobin (HbO₂) of erythrocytes is basic
v. The chloride ions diffuse from plasma into the erythrocytes to maintain ionic balance
(1) (i), (iii) and (v) are true, (ii) and (iv) are false
(2) (i), (iii) and (v) are false, (ii) and (iv) are true
(3) (i), (ii) and (iv) are true, (iii) and (v) are false
(4) (i), (ii) and (iv) are false, (iii) and (v) are true
✅ (1) (i), (iii) and (v) are true, (ii) and (iv) are false
26. Which of the following statements is/are true?
1. The pO₂ in deoxygenated blood is 40mm Hg
2. The pO₂in oxygenated blood is 95mmHg
3. The pO₂in the alveolar air is 104mm Hg
4. The pCO₂ in the alveolar air is 40mm Hg
5. The pCO₂ in deoxygenated blood is 95mm Hg
(1) 1, 2 & 3 are true
(2) 4 & 5 are true
(3) 1, 2, 3 & 4 are true
(4) 2, 3 & 5 are true
✅ (3) 1, 2, 3 & 4 are true
27. What will be the pO₂ and pCO₂ in the atmospheric air compared to those in the alveolar air?
(1) pO₂ lesser, pCO₂ higher
(2) pO₂ higher, pCO₂ lesser
(3) pO₂ higher, pCO₂ higher
(4) pO₂ lesser, pCO₂ lesser
✅ (2) pO₂ higher, pCO₂ lesser
28. The O₂-Hb dissociation curve turns to right side when
(1) Increase in PCO₂ (Bohr’s effect)
(2) Increase in temperature
(3) Increase in H⁺ ions
(4) All the above
✅ (4) All the above
29. 90% saturation of O₂ occurs at the pO₂ of
(1) 60 mm Hg
(2) 90 mm Hg
(3) 100 mm Hg
(4) 40 mm Hg
✅ (1) 60 mm Hg
Topic 4: GAS TRANSPORT, REGULATION OF RESPIRATION, DISORDERS
NEET: Previous Years Questions
30. Which of the following factors are favourable for the formation of oxyhaemoglobin in alveoli?
(1) High pO₂ and High pCO₂
(2) High pO₂ and Lesser H⁺ concentration
(3) Low pCO₂ and High H⁺ concentration
(4) Low pCO₂ and High temperature (NEET 2024)
✅ (2) High pO₂ and Lesser H⁺ concentration
31. Select the favourable conditions required for the formation of oxyhaemoglobin at the alveoli.
(1) High pO₂, low pCO₂, less H⁺, lower temperature
(2) Low pO₂, high pCO₂, more H⁺, higher temperature
(3) High pO₂, high pCO₂, less H⁺, higher temperature
(4) Low pO₂, low pCO₂, more H⁺, higher temperature (NEET 2021)
✅ (1) High pO₂, low pCO₂, less H⁺, lower temperature
32. Identify the wrong statement with reference to transport of oxygen.
(1) Higher H⁺ conc. in alveoli favours the formation of oxyhaemoglobin.
(2) Low pCO₂ in alveoli favours the formation of oxyhaemoglobin.
(3) Binding of oxygen with haemoglobin is mainly related to partial pressure of O₂.
(4) Partial pressure of CO₂ can interfere with O₂ binding with haemoglobin. (NEET 2020)
✅ (1) Higher H⁺ conc. in alveoli favours the formation of oxyhaemoglobin.
33. Due to increasing air-borne allergens and pollutants, many people in urban areas are suffering from respiratory disorder causing wheezing due to:
(1) benign growth on mucous lining of nasal cavity.
(2) inflammation of bronchi and bronchioles.
(3) proliferation of fibrous tissues and damage of the alveolar walls.
(4) reduction in the secretion of surfactants by pneumocytes. (NEET 2019)
✅ (2) inflammation of bronchi and bronchioles.
34. Which of the following options correctly represents the lung conditions in asthma and emphysema, respectively?
(1) Inflammation of bronchioles; Decreased respiratory surface
(2) Increased number of bronchioles; Increased respiratory surface
(3) Increased respiratory surface; Inflammation of bronchioles
(4) Decreased respiratory surface; Inflammation of bronchioles (NEET 2018)
✅ (1) Inflammation of bronchioles; Decreased respiratory surface
35. Which of the following is an occupational disorder?
(1) Anthracis
(2) Silicosis
(3) Botulism
(4) Emphysema (NEET 2018)
✅ (2) Silicosis
36. Reduction in pH of blood will
(1) decrease the affinity of haemoglobin with oxygen
(2) release bicarbonate ions by the liver
(3) reduce the rate of heartbeat
(4) reduce the blood supply to the brain. (NEET-I 2016)
✅ (1) decrease the affinity of haemoglobin with oxygen
37. Name the chronic respiratory disorder caused mainly by cigarette smoking. (NEET-I 2016)
(1) Respiratory acidosis
(2) Respiratory alkalosis
(3) Emphysema
(4) Asthma
✅ (3) Emphysema
38. Asthma may be attributed to
(1) inflammation of the trachea
(2) accumulation of fluid in the lungs
(3) bacterial infection of the lungs
(4) allergic reaction of the mast cells in the lungs. (NEET-I 2016)
✅ (4) allergic reaction of the mast cells in the lungs.
Model Questions
39. A large proportion of oxygen remains unused in the human blood even after its uptake by the body tissues. This O₂
(1) Raises the pCO₂ of blood to 75 mm of Hg.
(2) Can keep oxyhaemoglobin saturation at 96%.
(3) Acts as a reserve during muscular exercise.
(4) Helps to release more O₂ to the epithelial tissues.
✅ (3) Acts as a reserve during muscular exercise
40. Reduction in pH of blood will
(1) Decrease the affinity of haemoglobin with oxygen
(2) Release bicarbonate ions by the liver
(3) Reduce the rate of heartbeat
(4) Reduce the blood supply to the brain
✅ (1) Decrease the affinity of haemoglobin with oxygen
41. Blood carries CO₂ mainly in which form?
(1) Hb.CO₂
(2) NaHCO₃
(3) Carbonic acid
(4) Hb.CO₂ and CO
✅ (2) NaHCO₃
42. CO₂ is transported in three ways. They are
(1) As carbonic acid (7%), as carbamino haemoglobin (20-25%) & as bicarbonates (70%)
(2) As carbonic acid (7%), as carboxy haemoglobin (20-25%) and as bicarbonates (70%)
(3) As carbonic acid (7%), as carboxy haemoglobin (70%) and as bicarbonates (20-25%)
(4) As carbonic acid (7%), as carbamino haemoglobin (70%) & as bicarbonates (20-25%)
✅ (1) As carbonic acid (7%), as carbamino haemoglobin (20-25%) & as bicarbonates (70%)
43. The enzyme carbonic anhydrase takes part in
(1) Transport of O₂ in the form of oxyhaemoglobin
(2) Transport of CO₂ in the form of bicarbonates
(3) Transport of O₂ by physical solution
(4) Transport of CO₂ as carbamino haemoglobin
✅ (2) Transport of CO₂ in the form of bicarbonates
44. In CO₂ transport, percentage of CO₂ diffusing to RBC is
(1) 70%
(2) 23%
(3) 93%
(4) 7%
✅ (3) 93%
45. Inspiratory centre is located in
(1) Cerebellum
(2) Pons varoli
(3) Hypothalamus
(4) Medulla oblongata
✅ (4) Medulla oblongata
46. Rate of breathing is controlled by
(1) The amount of freely available oxygen
(2) Carbon dioxide
(3) Stress
(4) All the above
✅ (4) All the above
47. Match the following:
a b c d
(1) 4 2 5 1
(2) 5 3 2 1
(3) 2 4 1 3
(4) 3 1 4 2
✅ (3) 2 4 1 3