AQA BIOL2~3rd June 2013~AS Biology (Now Closed)

my feelings exactly, if i didn't have chemistry tomorrow i would be at the vodka by now

I got 342 but I got 37500

Do you not do 1250X30?

1 In 30 have the genetic disorder

1250:37500 is 1:30 ratio


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I put the same

i put similar shape to cytosine therefore complementary with gaunine. It forms a complementary base pair with Gaunine. Prevents cytosine from forming a complementary base pair with gaunine.

no idea though lol

I'll start the unofficial mark scheme, quote me and then add a question and we can debate the right answers.

1 a) Name part x

I put centromere

I know right. It was one of those qs where i thought 'omg if i could get this right i could do anything' and then i come on tsr and i see that someone wrote 'oh it was pretty stupid because the tube showed which nitrogen strands were present' and its just like not so clever after all

I know right. It was one of those qs where i thought 'omg if i could get this right i could do anything' and then i come on tsr and i see that someone wrote 'oh it was pretty stupid because the tube showed which nitrogen strands were present' and its just like not so clever after all

For the question do with meiosis where it asked for another way of variation beside independent segregation what did everyone put?

Was random fertilisation right?

Crossing over

Question 1
a) Centromere
b) joins to spindle fibers in metaphase and pulled apart in anaphase
c) different alleles
d) chromosomes not replicated into sister chromatids as figure 2 is prior to synthesis.
e) 3 chromosomes- 1 from each homologous pair( ie. one long,1 medium and one short)
f)crossing over

Question 2
a)similar organisms capable of breeding to produce fertile offspring
b)6.9 something
c)destruction of plants and growing of 1 dominating crop means less food sources, habitats for insects and use of pesticides

Question 3
a) groups within larger groups with no overlap
b) groups based on evolutionary relationships
c) animal A because least difference in amino acid sequence therefore DNA similar as DNA codes for amino acids
d)same number of differences however may code for different amino acids
f)hemoglobin not found in all organisms while respiration occurs in all

Somebody please continue so that we can finish this unofficial mark scheme

Getting iritated by the different interpretations for the 6 marker- Here are the correct marks.

-Active transport
- Lower water potential
-osmosis
- transpiration/evaperation
- Root pressure
- cohesion-tension theory

None of this symplastic/apoplastic rubbish

Getting iritated by the different interpretations for the 6 marker- Here are the correct marks.

-Active transport
- Lower water potential
-osmosis
- transpiration/evaperation
- Root pressure
- cohesion-tension theory

None of this symplastic/apoplastic rubbish

Everyone get 6 for the spiracle frequency ? Thumbs up if yes

haha that was me! apologies


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