A level
AQA
AS
BIOLOGY
7401/2
Paper 2
Final Mark scheme
June 2024
,Question Marking Guidance Mark Comments
1. Buffers changes in temperature; 1. Accept
2 descriptions of
2. (Provides a) cooling effect (via evaporation);
01.1 (2 x buffering changes
AO1 in temperature,
) e.g. resists
temperature
changes
Question Marking Guidance Mark Comments
1. Evaporation/transpiration (from the porous
pot);
2. Accept
2. Tension created moves water (upwards); ‘negative
3 pressure’ for
3. Cohesion maintains the column of water
tension or ‘water
01.2 OR (1 x pulled’ or
AO2, ‘suction’.
Cohesion is due to hydrogen bonds 2x
between water (molecules); AO3) Ignore adhesion
but reject mark
point 3 if
adhesion used to
describe
attraction
between water
molecules.
Question Marking Guidance Mark Comments
0.8/0.85/0.848/0.8478 (using 1
01.3 3.14); OR (1 x
0.8482 (using π on calculator) AO2
)
, Question Marking Guidance Mark Comments
Correct answer within range of 7 to 7.5 = 2
marks;; Incorrect but shows division by 5500 2
02.1 = 1 mark (2 x
AO2
OR )
Answer shows correct number but
incorrect decimal place eg /
0.72 = 1 mark;
Question Marking Guidance Mark Comments
Correct answer of ..52 x 1013 in any
correct mathematical form = 2 marks;;
Incorrect but shows 5250 in any 2
02.2 correct mathematical form = 1
(2 x
mark
AO2
OR )
Incorrect but answer shows first three
numbers as 252 = 1 mark;
Question Marking Guidance Mark Comments
1. Osmosis does not occur; 1. Accept no net
flow of water for
2. (Red blood) cells do not burst/lyse/shrink; osmosis.
2. Accept
2 crenation (of red
02.3 blood cells).
(2 x
AO2 1. and 2. Accept
) converse eg
osmosis would
occur and cells
would
burst/lyse/shrink.
2. Accept cells
would be
larger/smaller.
Question Marking Guidance Mark Comments
1. Binding/complex between antigen 1. Ignore reference
2
A and (antibody) anti-A; to (antibody) anti-
02.4 (2 x B in donor.
2. (Causes red blood) cells to join/clump; AO2
2. Reject
)
‘clot/clotting’.
AQA
AS
BIOLOGY
7401/2
Paper 2
Final Mark scheme
June 2024
,Question Marking Guidance Mark Comments
1. Buffers changes in temperature; 1. Accept
2 descriptions of
2. (Provides a) cooling effect (via evaporation);
01.1 (2 x buffering changes
AO1 in temperature,
) e.g. resists
temperature
changes
Question Marking Guidance Mark Comments
1. Evaporation/transpiration (from the porous
pot);
2. Accept
2. Tension created moves water (upwards); ‘negative
3 pressure’ for
3. Cohesion maintains the column of water
tension or ‘water
01.2 OR (1 x pulled’ or
AO2, ‘suction’.
Cohesion is due to hydrogen bonds 2x
between water (molecules); AO3) Ignore adhesion
but reject mark
point 3 if
adhesion used to
describe
attraction
between water
molecules.
Question Marking Guidance Mark Comments
0.8/0.85/0.848/0.8478 (using 1
01.3 3.14); OR (1 x
0.8482 (using π on calculator) AO2
)
, Question Marking Guidance Mark Comments
Correct answer within range of 7 to 7.5 = 2
marks;; Incorrect but shows division by 5500 2
02.1 = 1 mark (2 x
AO2
OR )
Answer shows correct number but
incorrect decimal place eg /
0.72 = 1 mark;
Question Marking Guidance Mark Comments
Correct answer of ..52 x 1013 in any
correct mathematical form = 2 marks;;
Incorrect but shows 5250 in any 2
02.2 correct mathematical form = 1
(2 x
mark
AO2
OR )
Incorrect but answer shows first three
numbers as 252 = 1 mark;
Question Marking Guidance Mark Comments
1. Osmosis does not occur; 1. Accept no net
flow of water for
2. (Red blood) cells do not burst/lyse/shrink; osmosis.
2. Accept
2 crenation (of red
02.3 blood cells).
(2 x
AO2 1. and 2. Accept
) converse eg
osmosis would
occur and cells
would
burst/lyse/shrink.
2. Accept cells
would be
larger/smaller.
Question Marking Guidance Mark Comments
1. Binding/complex between antigen 1. Ignore reference
2
A and (antibody) anti-A; to (antibody) anti-
02.4 (2 x B in donor.
2. (Causes red blood) cells to join/clump; AO2
2. Reject
)
‘clot/clotting’.
