Q. No.
Chemosensitive area of respiratory centre medulla is affected by
1. less and ions
2. less and ions
3. excess and H+ ions
4. excess and H+ ions.
The binding of Hb to oxygen is primarily related to
| 1. | Partial pressure of oxygen |
| 2. | Partial pressure of carbon dioxide |
| 3. | Hydrogen ion concentration |
| 4. | Temperature |
In the given diagram of a section of an alveolus with a pulmonary capillary, the basement substance would be present in the region shown by the letter:
| 1. | A | 2. | B |
| 3. | C | 4. | D |
The external intercostal muscles and the diaphragm contract:
| 1. | during inhalation |
| 2. | during exhalation |
| 3. | during both inhalation and exhalation |
| 4. | during neither inhalation nor exhalation. |
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
Approximately seventy percent of carbon dioxide absorbed by the blood will be transported to the lungs:
| 1. | as bicarbonate ions |
| 2. | in the form of dissolved gas molecules |
| 3. | by binding to R.B.C |
| 4. | as carbamino-haemoglobin |
Two friends are eating together at a dining table. One of them suddenly starts coughing while swallowing some food. This coughing would have been due to improper movement of:
| 1. | diaphragm | 2. | neck |
| 3. | tongue | 4. | epiglottis |
What is true about RBCs in humans?
| 1. | They carry about 20-25 per cent of CO2 |
| 2. | They transport 99.5 per cent of O2 |
| 3. | They transport about 80 per cent oxygen only and the rest 20 per cent of it is transported in dissolved state in blood plasma |
| 4. | They do not carry CO2 at all |
The majority of carbon dioxide produced by our body cells is transported to the lungs:
| 1. | dissolved in the blood |
| 2. | as bicarbonates |
| 3. | as carbonates |
| 4. | attached to haemoglobin |
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