# A2 Biology OCR June 2015 Revision Thread watch

1. can someone explain hardyweinberg for 7cii on this paper please

http://www.ocr.org.uk/Images/58628-q...nvironment.pdf
2. Can somebody explain flight or flight? In terms of all the noradrenaline etc
3. (Original post by peanutcracker20)
Can anyone explain how to do hardy weinberg for this question http://www.ocr.org.uk/Images/58628-q...nvironment.pdf its 7cii
Black = Dominant phenotype (p^2 and 2pq)
Red = Recessive phenotype (q^2)

Population size = 296 + 50 = 346

To work out q^2 we divide the number of recessive phenotype individuals by the total number of individuals. 296/346. (Don't round it here as that could lead to mistakes later).

q is just the square root of q^2 so square root 296/346 which gives 0.92
p = 1 - q. 1 - 0.92 = 0.08.
4. (Original post by medactuary)
wow how do you know that?! thank you!
I'm magic.
5. (Original post by peanutcracker20)
can someone explain hardyweinberg for 7cii on this paper please

http://www.ocr.org.uk/Images/58628-q...nvironment.pdf
this video helped me a lot for hardy weinberg
6. (Original post by bmunro)
You are just like me, I feel so stupid that I abused this exam till last minute and am still cramming now... I can't believe I didn't realise the amount there was that I couldn't remember and I worked to hard in previous weeks on it but it's all just gone from my memory don't think I will make uni now
same here its so frustrating
7. Good luck guys!!!!!!!!!!!!!!!! we can do it!!!
8. (Original post by Munrot07)
Black = Dominant phenotype (p^2 and 2pq)
Red = Recessive phenotype (q^2)

Population size = 296 + 50 = 346

To work out q^2 we divide the number of recessive phenotype individuals by the total number of individuals. 296/346. (Don't round it here as that could lead to mistakes later).

q is just the square root of q^2 so square root 296/346 which gives 0.92
p = 1 - q. 1 - 0.92 = 0.08.
thank you, helped a lot
9. Good luck everyone!

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10. When you learn the sliding filament theory in 5 minutes and you're like wow why was i bothered.
11. Dear University, I failed Biology because F215 was the 8th exam I've had on 8 consecutive school days.
Dear University, I failed Physics because Unit 5 was the 9th exam I've had on 9 consecutive school days.
Dear University, I failed Chemistry because what the hell was that NMR supposed to be
12. Any predictions?
13. (Original post by alexthehuman)
Any predictions?
Probably everything you haven't revised for lol
14. (Original post by Crystalz)
When you learn the sliding filament theory in 5 minutes and you're like wow why was i bothered.

Well I literally don't know that at all so I'm praying that doesn't come up

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15. What big questions have yet to come up? Have a feeling sliding filament theory hasn't yet..
16. (Original post by Shostakovish)
It is the absorbed - respired
Lol wat. Haha thanks
17. (Original post by GianluigiBuffon)
its just absorbed - respired fam
Lol thanks x'D
18. Time to face death guys... GOODLUCK!
19. Paper was meh. That's my chance of an A gone
20. Lots of suggest question. I don't know how I felt about that...

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