Question

Select the MOST CORRECT answer.

		Carbon dioxide is transported in the blood mostly bound to hemoglobin or dissolved in plasma.
		Hemoglobin has a higher affinity for oxygen than myoglobin, allowing a fairly rapid movement of oxygen from muscle to plasma during exercise.
		Bicarbonate ion is pumped into and out of the red blood cell by a chloride antiporter.
		Both a) and b) are correct and c) is incorrect.
		a), b) and c) are all correct.

Select the MOST CORRECT answer. Hemoglobin...

		is nearly saturated with oxygen in most tissues, regardless of the partial pressure of oxygen.
		exhibits different affinity for oxygen, depending on its environment.
		has four Heme groups where oxygen and carbon dioxide bind.
		Both a) and b) are correct and c) is incorrect.
		a), b) and c) are all correct.

Answer 1

1.Correct answer is option C - Bicarbonate ion is pumped into and out of the red blood cell by a chloride antiporter.

Explanation :

**Carbon dioxide is transported in the blood mostly bound to hemoglobin or dissolved in plasma is wrong statement. Carbon dioxide is mostly transported as bicarbonate ions.

**Hemoglobin has a higher affinity for oxygen tha myoglobin is wrong statement. Myoglobin has more affinity for oxygen than hemoglobin.

2. Correct answer is B- Hemoglobin exhibits different affinity for oxygen, depending on its environment

Explanation :

Affinity for oxygen depends on environmental factors like- pH, temperature, partial pressure of CO2.

** In tissues hemoglobin is not saturated with oxygen, the partial pressure of oxygen is less.CO2 binds with hemoglobin in tissues. When CO2 binds to Hb, the affinity for oxygen decreases.

**Hb has four Heme groups where oxygen and carbon dioxide bind is wrong statement.

Hb has 4 heme groups. Oxygen binds with heme group,but carbon dioxide binds to a terminal amino group.