Haemoglobin and gas exchange

How many polypeptide chains does Haemoglobin (Hb) consist of?

• One

• Two

• Three

• Four

Where in the Hb molecule do molecules of oxygen bind?

• To the haem group

• To amino acids in the polypeptide chains

• In the cytoplasm of the erythrocyte

• In the plasma

Which ion does Haemoglobin (Hb) contain in the haem group?

• Chloride

• Iron (Fe2+)

• Iron (Fe3+)

• Protons

Which of the following is not a means by which carbon dioxide is carried in the blood?

• Dissolved in the plasma as CO2

• Dissolved in the plasma as HCO3-

• Dissolved in the cytoplasm of the erythrocyte as HCO3-

• Bound to Hb directly

Which of the following is true about formation of oxyhemoglobin?

• it forms when pO₂ is low and dissociates when pCO₂ is low

• it forms when pO₂ is low and dissociates when pCO₂ is high

• it forms when pO₂ is high and dissociates when pCO₂ is high

• it forms when pO₂ is high and dissociates when pCO₂ is low

Using the graph, what does graph A represent?

• graph of fetal haemoglobin

• graph of sickle celled haemoglobin

• graph of adult haemoglobin

• graph of denatured haemoglobin

What is the name of the molecule formed when oxygen binds to haemoglobin?

• oxyhaemoglobin

• oxygen-haemoglobin

• carbaminohaemlobin

• oxyglobin

What colour line represents the oxygen saturation curve during intense exercise?

• blue

• black

• red

Gases will diffuse from areas of _______ pressure

• low to high

• high to low

Partial pressure of oxygen can be abbreviated to