In this bundle there are more than 5000 aqa a level biology questions and if you do every question and memorise the mark scheme you will get that A* without a doubt
1. (a) (i) Correct answer (0.5%) awarded two marks;;
answer involving decimal point in wrong place but derived
correctly / correct working only awarded 1 mark 2
(ii) Some fails to encounter chloroplasts/chlorophyll in producers
(e.g. some absorbed by water);
reflection;
inappropriate wavelength; max. 2
(b) Only a certain amount of light energy available / not enough energy left;
respiratory loss between each trophic level / loss in faeces; 2
(c) Incorporated in tissues of decomposers;
passed on to other organisms in decomposer food chain;
lost in respiration by decomposers; max. 2
(d) (i) Excites/raises energy level of electrons;
which pass to carriers/leave chlorophyll; 2
(ii) Fall in production of triose phosphate/no more triose phosphate produced;
triose phosphate production requires ATP/reduced NADP;
produced during passage of electrons along electron transport chain; 3
(e) Energy is available more rapidly because released in single reaction /
does not go through as many processes;
ATP releases its energy in small/manageable quantities; 2
(f) (i) Activity / needs of cell linked to level of ATP / ADP ;
link made between high level of one and low level of the other;
level of ADP linked to electron transport and ATP production; 3
(ii) Energy released as heat;
because not used to produce ATP; 2
[20]
2. (a) (i)
Stage Name of stage Location in cell
A Glycolysis Cytoplasm
B Krebs cycle / citric acid cycle / Mitochondrion (ignore
TCA cycle named part)
1 mark per row;; 2
(ii) 3; 1
(iii) To oxygen;
Produce water; 2
(b) (i) 4; 1
(ii) 34; 1
[answerfrom ( b)(i) (ii )] x 31] 100;
(c) (i) Correct calculation - 2880
Answer correct from calculation;
OR
Correct answer from (b) / 41% (no working) = 2 marks;; 2
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