A2 Biology OCR June 2015 Revision Thread

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"Shivering can also be a response to a fever, as a person may feel cold. During fever the hypothalamic set point for temperature is raised. The increased set point causes the body temperature to rise (pyrexia), but also makes the patient feel cold until the new set point is reached. Rigor occurs because the patient's body is effectively shivering in a physiological attempt to increase body temperature to the new set point." -Wikipedia

How on earth were we meant to know this.
Thanks OCR!

That's surely obvious, you just use your knowledge that shivering increases body temperature and say why...

Reply 2601

kingcobra007

Original post by BioAgent

Surely it was outer membrane for q1?

nah it was pointing to the inner membrane

Reply 2602

AsianBeauty

Mark for a* ?

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Reply 2603

nombo

http://www.nhs.uk/Conditions/Dialysis/Pages/How-haemodialysis-is-performed.aspx Ok, from this link, I THINK that haemo filters out more of your blood in one go than peritoneal? Sounds about right... I didn't get that, not sure what I wrote :/
Thanks so much OCR smd

Reply 2604

NilaJ

Can people PLEASE help me with what all the questions were, I'm writing out an unofficial mark scheme now!

Reply 2605

vincentjack

Original post by PinkElephant16

Guys pls add anything you remember

peritoneal dialysis needs to be done more often because it only gets a small supply of blood from the capillaries around the peritoneum, but in haemodialysis all of the bodys blood is passed through the machine

during fever the thermoregulatory set point is higher, so even though you're hot you shiver to increase your body temperature

Reply 2606

Dark Elixir

Original post by tewas

would they accept grana not granum?

also, i wrote underneath the lines in the big essay question and not on the additional sheet but it wasn't out of the boxes, would that be okay?

Yeah, on all of the past mark schemes they accept grana :smile:

It was
M
S
M

Hope its like 40/60 to get an A.

Reply 2609

Dark Elixir

Original post by THEMathlete

I put range bar... When it was an error bar -.-

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Lots of people have put range bar, myself included!

Reply 2610

MiniSlash

Regarding the 'biochemistry question'

I've seen a lot about the Calvin Cycle and such, but I went at it from a different angle:

-Increase in light intensity
-Increase in transpiration
-Less water available for photolysis
-Less photolysis results in less electrons available for chemiosmosis and non-cyclic photophosphorlyation
-Less ATP produced

Would I be wrong? I thought I was being all clever and I'm interested in what you guys think.

Reply 2611

username911777

Original post by THEMathlete

I put range bar... When it was an error bar -.-

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Pretty sure it's a range bar, why would there be an error bar measuring the percentage of people

I worked out the difference between the lowest and highest and it gave the range as well