Transport of Carbon Dioxide

Q.

Assertion (A) $C{O}_2$ transport occurs very fast through RBCs.
Reason (R) Enzyme carbonic anhydrase is absent in blood plasma.

1. Both A and R are correct and R is the correct explanation of A

2. Both A and R are correct, but R is not correct explanation of A

3. A is correct, but R is incorrect

4. A is incorrect, but R is correct.

Q.

The vital capacity of the lungs includes

1. IRV + TV

2. IRV + TV + ERV

3. ERV + TV

4. ERV + RV

5. RV + ERV + TV + IRV

Q.

Is magnesium good for circulation?

Q. Bulk of carbon dioxide released from body tissues into the blood is present as

1. bicarbonate in blood plasma and RBCs
2. free ${CO}_2$ in blood plasma
3. 70% carbamino-haemoglobin and 30% as bicarbonate
4. carbamino-haemoglobin in RBCs

Q. Write briefly about Bohr effect and Haldane effect and their significance.

Q. Bohr effects is the effects of :

1. $C{O}_2$ on haemoglobin
2. $C{O}_2$ on oxyhaemoglobin
3. $C{O}_2$ on RBCs
4. $O_2$ on haemoglobin

Q. Approximately 70% of $C{O}_2$ is absorbed by the blood and will be transported to the lungs as ___________.

1. bicarbonate ions
2. carbamino haemoglobin
3. gaseous form
4. carbon monoxide

Q. ______________ is formed by the reversible combination of carbon dioxide with haemoglobin.

1. Carboxyhaemoglobin
2. Carbaminohaemoglobin
3. Oxyhaemoglobin
4. Bicarbonate ions

Q.

Hamburger shift is also known as

1. Bicarbonate shift

2. Chloride shift

3. Potassium shift

4. All of the above

Q. In Bohr effect, curve shift to right

1. PCO${}_2$ decreases and PO${}_2$ increases
2. PCO${}_2$ increases and PO${}_2$ increases
3. PCO${}_2$ increases and PO${}_2$ decreases
4. PCO${}_2$ increases and PO${}_2$ decreases and pH increases

Q. $C{O}_2$ dissociates from carbamino-haemoglobin when:

1. $pC{O}_2\text{is high and}p{O}_2\text{is low}$
2. $p{O}_2\text{is high and}pC{O}_2\text{is low}$
3. $pC{O}_2\text{and}p{O}_2\text{are equal}$
4. $\text{None of the above}$

Q.

Carbon dioxide dissociates from carbaminohaemoglobin when

1. Partial pressure of carbon dioxide is high and partial pressure of oxygen is low.

2. Partial pressure of carbon dioxide is low and partial pressure of oxygen is high.

3. Partial pressures of both oxygen and carbon dioxide are equal.

4. None of the above.

Q.

Most of the carbon dioxide transported in our blood is

1. dissolved in the plasma

2. as carbaminohaemoglobin

3. as bicarbonate

4. bound to the heme of haemoglobin

Q. Approximately 70% of $C{O}_2$ is absorbed by the blood and will be transported to the lungs as ___________.

1. bicarbonate ions
2. carbamino haemoglobin
3. gaseous form
4. carbon monoxide

Q.

Which one is a cofactor of carbonic anhydrase?

1. Zn

2. Fe

3. Cu

4. Mg

Q. pCO2 in oxygenated blood ?

Q. Haldane effect refers to

1. More acidity in the blood
2. Less acidity in the blood
3. More basicity in the blood
4. Less basicity in the blood

Q. The electrical charge of the RBC is maintained during carbon dioxide transport by the inward movement of

1. Hydrogen ions
2. Oxygen
3. Chloride ions
4. Bicarbonate ions

Q. Which of the following statements are correct/incorrect?
I. The blood transports carbon dioxide comparatively easily because of its highest solubility.
II. Approximately 89% of carbon dioxide is transported being dissolved in the plasma of blood.
III. The carbon dioxide produced by the tissues, diffuses passively into the blood stream and passes into red blood corpuscles and react with water to form $H_{2}C{O}_3$.
IV. The oxyhaemoglobin $\left(Hb{O}_2\right)$ of the erythrocytes is basic.
V. The chloride ions diffuse from plasma into the erythrocytes to maintain ionic balance.

1. I, III and V are correct. II and IV are incorrect
2. I, III and V are incorrect. II and IV are correct
3. I, II and IV are correct. III and V are incorrect
4. I, II and IV are incorrect. III and V are correct

Q.

What are the major transport mechanisms for CO₂? Explain.