Haemoglobin - exam practice

haemoglobin has a higher affinity for oxygen

haemoglobin releases oxygen more readily

the change in partial pressure of carbon dioxide causes a Bohr effect

the decrease in percentage of carbon dioxide causes the curve to shift to the left

carbon dioxide and carbon monoxide bind to one site, oxygen binds to a different site

carbon dioxide and oxygen bind to one site, carbon monoxide binds to a different site

carbon monoxide and oxygen bind to one site, carbon dioxide binds to a different site

carbon monoxide, oxygen and carbon dioxide all bind to different sites

in high partial pressure of oxygen and high partial pressure of carbon dioxide, the affinity of haemoglobin for oxygen increases

in high partial pressure of oxygen and low partial pressure of carbon dioxide, the affinity of haemoglobin for oxygen decreases

in low partial pressure of oxygen and high partial pressure of carbon dioxide, the affinity of haemoglobin for oxygen decreases

in low partial pressure of oxygen and low partial pressure of carbon dioxide, the affinity of haemoglobin for oxygen is unchanged

to compensate for the low percentage saturation of haemoglobin

to enable haemoglobin to unload more oxygen in the tissues by the Bohr effect

to ensure that haemoglobin is almost 90% saturated when it reaches the tissues

to increase the number of mitochondria in the blood for ATP production

1 and 2

3 and 4

3 only

4 only

carbaminohaemoglobin

haemoglobinic acid

hydrogencarbonate ions

oxyhaemoglobin

1 and 2

1 and 4

2 and 3

3 and 4

1

2

4

8

each of the four polypeptide chains is combined with an identical haem group

each polypeptide chain has a quaternary structure

the quaternary structure of each polypeptide chain contains ionic bonds

two polypeptide chains contain an alpha haem group and two contain a beta haem group

CO₂ + H₂O→ H₂CO₃

CO₂ + Hb → HbCO₂

H⁺ + Hb → HHb

Hb + 4O₂ → HbO₈

alpha helices

beta sheets

polypeptide chains

haem groups

the binding of the first oxygen molecule has no effect on the binding of subsequent oxygen molecules

the binding of the first oxygen molecule makes it harder for subsequent oxygen molecules to bind

the binding of the first oxygen molecule makes it easier for subsequent oxygen molecules to bind

the binding of oxygen molecules is completely independent of other molecules

because these tissues have a lower pH

because these tissues have a higher pH

because these tissues have a lower temperature

because these tissues have a higher temperature

it increases the affinity

it decreases the affinity

it does not affect the affinity

it reverses the affinity

take up oxygen more easily and release it more easily

take up oxygen more easily but release it less easily

take up oxygen less easily and release it more easily

take up oxygen less easily but release it less easily