Haemoglobin

Question 1

How is the red blood cell adapted?

Answer 1

bi-concave shape ( increases SA: VOL and short diff. pathway)

contains only haemoglobin ( which increases O2 capacity)

flexible (can bend through narrow capillaries)

Question 2

Describe the four structures of a red blood cell

Answer 2

primary= sequence of amino acids in the four polypeptide chains

secondary=each chain coiled into a helix

tertiary= filed into precise shape essential for its function

quarternary= all polypeptides link to form an almost spherical molecules, each polypeptide is associated with a beam group ( Fe2+)

Question 3

How many o2 molecules per HB molecule?

Answer 3

4

Question 4

Where does Loading/associating occur?

Answer 4

in the lungs

Question 5

Where does unloading/dissociating occur?

Answer 5

in the tissue

Question 6

What does ‘high affinity’ mean?

Answer 6

it can uptake o2 easily but releases it less easily

Question 7

What is the role of HB?

Answer 7

to transport oxygen

Question 8

How does the HB molecules adapted to different oxygen partial pressures?

Answer 8

it can change its affinity

by changing its 3 in the presence of substances eg. co2
in co2 it binds to the o2 more loosely so o2 can be released

Question 9

Why are there different haemoglobins?

Answer 9

different amino acid sequence

different oxygen-binding properties

Question 10

What is an erythrocyte?

Answer 10

red blood cell

Question 11

The oxygen dissociation curve for haemoglobin shifts to the right during vigorous exercise.

Explain the advantage of this shift.

Answer 11

Lower affinity for oxygen / releases more oxygen / unloads more readily;
(To) muscles / tissues / cells
(For) high / rapid respiration