AQA A-Level Biology paper 2 11th June 2018 unofficial markscheme

Wasn’t it 83 to the power of 2

I said that those who did not have the dominant allele would die due to lack of
energy from the milk. Those with the advantageous allele would survive and reproduce and pass on this allele to their offspring increasing the frequency of the lactase allele.

Please comment any questions you remember

Effect of reduced Light dependant reactions (2)
Less ATP And less reduced NADP produced

Where is rubisco found (1)
Stroma

Effect of rubisco activase on rubisco (4)

Why apparatus was left for a few hours (1)
Allow respiration rate to stabilise
Allow pressure change to occur

Why colour moved (1)
O2 absorbed so reduces pressure

Potometer maths question (2)
0.049

Why log was used (1)

Why yeast died during death phase (1)

Multiple choice (1)
3rd option

Size of new population (2)
296826

Cells in a tumour (2)
1.93x10^25

Enzymes in forming DNA fragments (2)
DNA ligase
Restriction endonuclease

Difference in blood flow (1)
1.3

How chloride ion prevent the nerve impulse from carrying on in the post synaptic neurone (3marks)

Causes hyperpolisaton so depolaristion doesn’t occour and therefore action potentials don’t pass on

Why actual ratio was different than expected (2)
Small sample size
Fertilisation is random

Explain results of offspring genotype (3)

Actual ratio (2)
9:3:3:1

Hardy wienberg (2marks)
43%

Why iPS was better (4)

I wrote about hypermethylation

I said it remains almost constant because the number of trees didn't change otherwise the graph would've changed

Yh I said all that but also said in those areas the cattle milk was one of the main sources of food so people consumed this as much as any other sources of food then said everything else you said

I thought this but then, I said the large trees blocked out the light so plants underneath photo synthesised less producing less glucose and organic materials which make up energy and biomass for NPP so net there is a reduction in NPP

I thought this but then, I said the large trees blocked out the light so plants underneath photo synthesised less producing less glucose and organic materials which make up energy and biomass for NPP so net there is a reduction in NPP

For the actual ratio different to expected I wrote linkage of genes and epistasis

The question was about tumour suppressor genes why would you want to write about oncogenes

I wrote both methylation and gene mutation, i wasn't sure what they meant by alterations to it

I wrote both methylation and gene mutation, i wasn't sure what they meant by alterations to it