Gaseous Exchange

Multiple Choice

What is the primary function of haemoglobin in the human body?

• To carry carbon dioxide

• To carry oxygen

• To regulate blood pressure

• To produce energy

Multiple Choice

What is the effect of one molecule of O₂ binding to a haemoglobin subunit?

• It decreases the affinity for oxygen

• It has no effect on the other subunits

• It increases the affinity for oxygen

• It causes the haemoglobin to release carbon dioxide

Multiple Choice

What atom is attached to each porphyrin ring of haem group consist?

• Magnesium

• Zinc

• Iron

• Chlorine

Multiple Choice

What is the chemical equation representing the binding of haemoglobin with oxygen?

• Hb + 4O₂ → HbO₂

• Hb + O₂ → HbO

• Hb + 2O₂ → HbO₂

• Hb + O₂ → HbO₂

Multiple Select

What are the three ways of CO₂ transport from respiring tissues to lungs?

• Dissolved CO₂ in blood plasma

• As bicarbonate ion.

• As carbominohaemoglobin

• Bound to the amino group of hemoglobin.

• Bound to the haem group of haemoglobin

Multiple Choice

What does the oxygen dissociation curve of hemoglobin illustrate about the relationship between oxygen saturation and partial pressure of oxygen (P_O2)?

• It shows a linear relationship

• It shows a parabolic relationship

• It shows a sigmoidal relationship

• It shows no relationship

Multiple Choice

What does the sigmoidal shape of the oxygen dissociation curve indicate about the binding of haemoglobin with oxygen?

• It indicates a linear relationship

• It shows cooperativity in binding

• It suggests no affinity changes

• It represents a constant saturation

Multiple Choice

What happens to the saturation of hemoglobin with oxygen (O₂) at very high partial pressures (P0₂) at the lungs?

• It decreases to 70%

• It remains at 100%

• It increases to 98%

• It becomes zero

Multiple Select

What does the steepest part of the oxygen dissociation curve indicate about the release of O₂ from hemoglobin?

• It indicates a low saturation of hemoglobin

• It indicates the cooperative binding of haemoglobin with O₂

• It indicates a rapid release of O₂

• It indicates a slow release of O₂

Multiple Choice

What is the percentage of oxygen unloaded to tissues during exercise?

• 28%

• 80%

• 70%

• 98%

Multiple Choice

What is the percentage of oxygen unloaded to tissues at rest?

• 28%

• 80%

• 70%

• 98%

Multiple Choice

What is the primary function of myoglobin in muscle tissue?

• To transport carbon dioxide

• To store oxygen

• To release carbon dioxide

• In charge of gaseous exchange

Multiple Choice

What are the similarities between the oxygen dissociation curves of myoglobin and hemoglobin?

• Both curves show the increase in saturation with O₂ when P_O2 is high

• Both curves show the increase in dissociation with O₂ when P_O2 is low

• Both curves are identical in shape

• Both curves are affected by pH levels

Fill in the Blanks

The central chemoreceptor detech pH change in

fluid.

Fill in the Blanks

Inspiratory center send impulse to diaphragm via

nerves.

Multiple Select

Stomata close during the ___?

• day
• hot and dry day

• noon

• night

Poll

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