General
✓✗A worker in a stone quarry develops breathing difficulty with fibrosis of the lungs. The most likely cause is
- cigarette smoking alone
- long exposure to dust
- an allergy to pollen
- deficiency of vitamin C
General
✓✗The respiratory rhythm centre is primarily responsible for
- regulation of the heart rate only
- regulation of respiration
- digestion of food in the gut
- regulation of body temperature only
General
✓✗The additional volume of air a person can expire by a forcible expiration is the
- tidal volume
- inspiratory reserve volume
- residual volume
- expiratory reserve volume
General
✓✗Which of the following statements about CO2 transport are correct?
A. About 70% is carried as bicarbonate.
B. About 20−25% is carried as carbamino-haemoglobin.
C. About 7% is dissolved in plasma.
D. About 97% is carried by haemoglobin.
Choose the correct answer from the options given below.
A. About 70% is carried as bicarbonate.
B. About 20−25% is carried as carbamino-haemoglobin.
C. About 7% is dissolved in plasma.
D. About 97% is carried by haemoglobin.
Choose the correct answer from the options given below.
- A and D only
- B, C and D only
- A, B, C and D
- A, B and C only
General
✓✗Which of the following factors are favourable for the formation of oxyhaemoglobin in the alveoli?
- Low pCO2 and high H+ concentration
- High pO2 and high pCO2
- Low pCO2 and high temperature
- High pO2 and lesser H+ concentration
General
✓✗Which of the following animals has no special respiratory organ?
- Cockroach
- Pigeon
- Planaria (a flatworm)
- Rohu (a fish)
General
✓✗The pO2 of tissues is 40 mm Hg at rest. During heavy exercise it falls further. As a result,
- the oxygen dissociation curve disappears
- less oxygen dissociates in the tissues
- more oxygen dissociates in the tissues
- haemoglobin stops carrying oxygen at all
General
✓✗Which of the following correctly describes CO2 transport from tissues to lungs?
- It forms bicarbonate and carbamino-Hb, freed in lungs
- It is carried only by the platelets to the lungs
- It is excreted through the kidneys and not lungs
- It is converted to glucose while in the blood
General
✓✗Which of the following would be expected to decrease the rate of diffusion of oxygen in the lungs?
- Increase in the number of functional alveoli
- Increase in the blood flow through alveolar capillaries
- Increase in the alveolar pO2
- Thickening of the diffusion membrane by fibrosis
General
✓✗Carbon dioxide produced during catabolic reactions has to be
- kept in the lungs permanently as a reserve
- released from the cells, as it is harmful
- stored in the cells for later energy use
- converted into glucose inside the same cells
General
✓✗A large proportion of oxygen remains unused in human blood even after its uptake by the body tissues. This O2
- is enough to keep oxyhaemoglobin saturation at 96%
- helps in releasing more O2 to the epithelial tissues
- acts as a reserve during muscular exercise
- raises the pCO2 of blood to 75 mm Hg
General
✓✗The inspiratory reserve volume averages
- 1100−1200 mL
- 500 mL
- 2500−3000 mL
- 1000−1100 mL
General
✓✗Which of the following are true for normal inspiration?
A. Pulmonary volume decreases.
B. The diaphragm contracts.
C. External intercostal muscles contract.
D. Intra-pulmonary pressure falls below atmospheric pressure.
Choose the correct answer from the options given below.
A. Pulmonary volume decreases.
B. The diaphragm contracts.
C. External intercostal muscles contract.
D. Intra-pulmonary pressure falls below atmospheric pressure.
Choose the correct answer from the options given below.
- A, B, C and D
- B, C and D only
- A, B and C only
- A and D only
General
✓✗A person breathes 15 times a minute with a tidal volume of 450 mL. The volume of air moved per minute is
- 9000 mL
- 675 mL
- 4500 mL
- 6750 mL
General
✓✗When the chemosensitive area is activated by excess CO2, the respiratory process is adjusted so that
- more CO2 is retained in blood
- oxygen is stored in the lungs
- breathing stops for some time
- these substances are eliminated