# AS Biology Edexcel IAL Unit 1 & 2 2015 watch

1. (Original post by Mushi123)
Guys what about the 3 mark question about hiw to calculate mean and also the reliability and improvement part?? And the one on how parents could calculate the probability of their child having the disease? Do we need to draw a genetic criss diagram?
how to calculate mean I just said you find the difference in heart rate after drinking caffeine for each student and divide it by 3 to get the mean increase in heart rate.

reliability - three repeats for each student, make sure the caffeine content of each drink is measured accurately so the consumption is the same for each student.

improvement - control all other variables that affect heart rate, for example stress levels and activity levels - before and after drinking caffeine the students should be resting, they should also be in the same environment/surroundings when the test is undergone to isolate the key variable of caffeine

how to calculate probability - described saying a genetic inheritance diagram could be used and each parent was heterozygous so had Tt alleles meaning there was a 1/4 or 25% chance of their child being a sufferer after crossing their gametes, it said describe so they weren't looking for you to draw anything I don't think
2. (Original post by rawanhaak)
what about the 3 mark question about how to calculate mean and also the reliability and improvement part?? And the one on how parents could calculate the probability of their child having the disease? Do we need to draw a genetic cross diagram?
3. (Original post by Mushi123)
Guys what about the 3 mark question about how to calculate mean and also the reliability and improvement part?? And the one on how parents could calculate the probability of their child having the disease? Do we need to draw a genetic cross diagram?
Go up a bit. And i did draw a diagram because my answer did not make any sense. You do not have to, though. How? By explaining how to draw the diagram, i believe
4. (Original post by AJC1997)
how to calculate mean I just said you find the difference in heart rate after drinking caffeine for each student and divide it by 3 to get the mean increase in heart rate.

reliability - three repeats for each student, make sure the caffeine content of each drink is measured accurately so the consumption is the same for each student.

improvement - control all other variables that affect heart rate, for example stress levels and activity levels - before and after drinking caffeine the students should be resting, they should also be in the same environment/surroundings when the test is undergone to isolate the key variable of caffeine

how to calculate probability - described saying a genetic inheritance diagram could be used and each parent was heterozygous so had Tt alleles meaning there was a 1/4 or 25% chance of their child being a sufferer after crossing their gametes, it said describe so they weren't looking for you to draw anything I don't think
Thanks a ton..the answers seemed to have matched..and about the probability thing..when i saw 4 marks i was a but flustered so i wrote the idea then drew a genetic diagram and wrote down the probablity as well thanks..hat do you think the grade boundary will be? As in equivalent tothe full ums marks?
5. (Original post by Mushi123)
They asked how a graoh of women of 190 cm would look like! I wrote it will be lower than that of men with 160but higher than rest of the 2 female groups..
That was me panicking and reading the question wrong wooohooo. How marks was there for this?
6. (Original post by Mushi123)
Thanks a ton..the answers seemed to have matched..and about the probability thing..when i saw 4 marks i was a but flustered so i wrote the idea then drew a genetic diagram and wrote down the probablity as well thanks..hat do you think the grade boundary will be? As in equivalent tothe full ums marks?
Can we just wish they are low😭😭😭😭😭
7. (Original post by AJC1997)
how to calculate mean I just said you find the difference in heart rate after drinking caffeine for each student and divide it by 3 to get the mean increase in heart rate.

reliability - three repeats for each student, make sure the caffeine content of each drink is measured accurately so the consumption is the same for each student.

improvement - control all other variables that affect heart rate, for example stress levels and activity levels - before and after drinking caffeine the students should be resting, they should also be in the same environment/surroundings when the test is undergone to isolate the key variable of caffeine

how to calculate probability - described saying a genetic inheritance diagram could be used and each parent was heterozygous so had Tt alleles meaning there was a 1/4 or 25% chance of their child being a sufferer after crossing their gametes, it said describe so they weren't looking for you to draw anything I don't think
my answers are quite similar to yours so thats kinda great
8. (Original post by Mushi123)
Thanks a ton..the answers seemed to have matched..and about the probability thing..when i saw 4 marks i was a but flustered so i wrote the idea then drew a genetic diagram and wrote down the probablity as well thanks..hat do you think the grade boundary will be? As in equivalent tothe full ums marks?
np, yeah that question was odd imo, it would have been so much easier if they just said 'show, using a diagram, what the probability of their child being a sufferer is' but describing it was strange, I think it should be right though. No idea about boundaries, probably average boundaries? 60/80 for an A?
9. Can we give a value ? Coz I wrote a value for the dm^3 per minute . Which was higher than the rest of the females but lower than that of the males.
10. (Original post by Sal296)
Can we give a value ? Coz I wrote a value for the dm^3 per minute . Which was higher than the rest of the females but lower than that of the males.
I think they will do accept it because apparently it is what they wanted anyway
11. Such vauge questions, last years paper was heaps better. What did you guys write for fibrous protein structure? Is it a compact molecule?
12. i said we can improve experiment by using daphnia instead and i followed it by an explanation
13. (Original post by Sal296)
Such vauge questions, last years paper was heaps better. What did you guys write for fibrous protein structure? Is it a compact molecule?
i thought globular protein is compact right? but i messed up this q
didnt revise that part
14. (Original post by Sal296)
Such vauge questions, last years paper was heaps better. What did you guys write for fibrous protein structure? Is it a compact molecule?
I am not sure if it is :/ it has little or no tertiarty structure. formed from long parallel polypeptide chain with occasional cross linkage forming a fibre. This made it ideal for its structural function and i actually talked about the amino acid linked by peptide bonds
15. i hope grade boundaries r low.
16. For me, there was a teacher because I can't write with my hand, I had to seriously spell every freaking word she wrote and I think I messed up in this exam

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17. What did you write for why can high dosesof heparin br used to treat people who are likely to get clots?
18. Increase clotting time so makes blood clotting left often or very slow . Dunno
19. What was the last question in the whole paper?? wasn't it about "Explain why people with cystic fibrosis have less amount of air breathed out"
20. Can someone please tell what the experiment was for the cooking time on potatoes please ? Like what did ya"ll write?

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