Breathing and Exchange of Gases

Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R. In the light of the above statements, choose the correct answer from the options given below.

1. A is true but R is false.
2. A is false but R is true.
3. Both A and R are true and R is the correct explanation of A.
4. Both A and R are true but R is NOT the correct explanation of A

Vital capacity of lung is .

1. IRV + ERV + TV + RV
2. IRV + ERV + TV − RV
3. IRV + ERV + TV
4. IRV + ERV

Under normal physiological conditions in human beings every 100 ml of oxygenated blood can deliver ml of O2 to the tissues.

1. 2 ml
2. 5 ml
3. 4 ml
4. 10 ml

Which of the following is not the function of conducting part of respiratory system?

1. It clears inhaled air from foreign particles
2. Inhaled air is humidified
3. Temperature of inhaled air is brought to body temperature
4. Provides surface for diffusion of O2 and CO2

Identify the region of human brain which has pneumotaxic centre that alters respiratory rate by reducing the duration of inspiration.

1. Cerebrum
2. Medulla
3. Pons
4. Thalamus

Which of the following statements are correct with respect to vital capacity? Choose the most appropriate answer from the options given below :

1. A and E only
2. B, D and E only
3. A, C and D only
4. A, C and E only

Select the favourable conditions required for the formation of oxyhaemoglobin at the alveoli.

1. Low pO2, low pCO2, more H+, higher temperature
2. High pO2, low pCO2, less H+, lower temperature
3. Low pO2, high pCO2, more H+, higher temperature
4. High pO2, high pCO2, less H+, higher temperature.

The partial pressures (in mm Hg) of oxygen (O2) and carbon dioxide (CO2) at alveoli (the site of diffusion) are :

1. pO2 = 159 and pCO2 = 0.3
2. pO2 = 104 and pCO2 = 40
3. pO2 = 40 and pCO2 = 45
4. pO2 = 95 and pCO2 = 40

Select the correct events that occur during inspiration.

1. Only (iv)
2. (iii) and (iv)
3. (i), (ii) and (iv)
4. (i) and (ii)

Identify the wrong statement with reference to transport of oxygen.

1. Binding of oxygen with haemoglobin is mainly related to partial pressure of O2
2. Partial pressure of CO2 can interfere with O2 binding with haemoglobin
3. Higher H+ conc. in alveoli favours the formation of oxyhaemoglobin
4. Low pCO2 in alveoli favours the formation of oxyhaemoglobin