x Turn on thread page Beta

# OCR Biology A Exam Thread (Breadth - May 26, 2016 and Depth - June 7, 2016) watch

1. (Original post by JStebz)
Tachycardia is when your heart rate is too fast (eg 100bpm)
Ectopic heart beats are when the heart beats too early, followed by a long pause
Fibrillation is when there is an irregularly timed heart beat

and that's all you need to know
Thank you so much
2. Oh I might start revising, what's on the exam?
3. (Original post by 4nonymous)
When you have an answer for t you want to compare it in the given table. You need to always look at the p value of 0.05 (just ignore the others, IDK why but for biology you use this). Then you want to calculate the degrees of freedom= (n-1)+(n-1) where n is the number of data that you have. This will also be in the table and then you choose the value which is equal to both of those values. So for example, if your degrees of freedom is 26 and p=0.05 look across here and see where they meet. Then using that value there and your answer you can work out if the null hypothesis should be rejected.

If your t value is much greater then the two areas/habitats (whatever is being tested) are significantly different due to a biological factor and not due to chance
In this case you reject the null hypothesis.

Thats all you need to know.
Thank you
4. (Original post by 4nonymous)
When you have an answer for t you want to compare it in the given table. You need to always look at the p value of 0.05 (just ignore the others, IDK why but for biology you use this). Then you want to calculate the degrees of freedom= (n-1)+(n-1) where n is the number of data that you have. This will also be in the table and then you choose the value which is equal to both of those values. So for example, if your degrees of freedom is 26 and p=0.05 look across here and see where they meet. Then using that value there and your answer you can work out if the null hypothesis should be rejected.

If your t value is much greater then the two areas/habitats (whatever is being tested) are significantly different due to a biological factor and not due to chance
In this case you reject the null hypothesis.

Thats all you need to know.
Hey! I'm really panicking.. Can you please go over the specific immune bit with the T lymphocytes and B lymphocytes. I understand phagocytosis.
5. (Original post by Cherx)
Hey! I'm really panicking.. Can you please go over the specific immune bit with the T lymphocytes and B lymphocytes. I understand phagocytosis.
So after phagocytosis, the antigen is represented on the plasma membrane of an antigen presenting cell. This is recognised by T lymphocytes. The T lymphocyte with the complementary receptor to the shape of the antigen is selected (clonal selection). This then divides by mitosis (clonal expansion) and the resulting cells can then differentiate into other cells:
These include:
T-helper which uses interleukins to communicate with other cells and stimulates clonal expansion of B lymphocytes
T-killer which kills any infected cells hence destroying the pathogen
T memory which provides long term immunity
T regulatory which shuts down the immune response after the pathogen is dealt with.

Once the B lymphocytes are active they also divide by mitosis and can differentiate into the following:
B memory cells which provide long term immunity
Plasma cells which produce antibodies
6. Lol I though I could understand cardiac cycle a couple hours before the exam. RIP
7. Difference between humoral and cell mediated response?
8. Could someone briefly explain phagocytosis and the macrophages stuff please. Would be very appreciated
9. (Original post by OddFuturez)
Lol I though I could understand cardiac cycle a couple hours before the exam. RIP
I posted what you need to know on the previous page or so if you want to take a look.
10. predictions for the two six mark questions today?
11. There is almost 100% chance that there will be stuff on the heart and enzymes in this paper as nothing about them was in the last paper.

Good luck to everyone.
12. (Original post by KappaRoss)
There is almost 100% chance that there will be stuff on the heart and enzymes in this paper as nothing about them was in the last paper.

Good luck to everyone.
Thanks! And good luck to you too
13. (Original post by andy135)
predictions for the two six mark questions today?
Some possibilities
Describe the 2 theories of enzyme action
Cardiac cycle
Specific immune system

Or they could be stupid and tell us to write about a practical
14. (Original post by asinghj)
Some possibilities
Describe the 2 theories of enzyme action
Cardiac cycle
Specific immune system

Or they could be stupid and tell us to write about a practical
Or sampling method
15. (Original post by asinghj)
Some possibilities
Describe the 2 theories of enzyme action
Cardiac cycle
Specific immune system

Or they could be stupid and tell us to write about a practical
Thanks, yeah hopefully we don't get a practical question..
And are the two theories of enzyme action that youre talking about the induced fit and lock and key or something else?
16. (Original post by andy135)
Thanks, yeah hopefully we don't get a practical question..
And are the two theories of enzyme action that youre talking about the induced fit and lock and key or something else?
Yeah induced fit and lock and key.. At least one will pop up
17. (Original post by 4nonymous)
Or sampling method
I really hope so.. That's the easiest topic in bio
18. The exam actually went better than I thought it would go!

No cardiac cycle, no transpiration/translocation, no transport in plants, no immunology and no biodiversity!

Posted from TSR Mobile
19. Defo got a D lol
20. (Original post by OddFuturez)
Defo got a D lol
Same... Lmao

TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

This forum is supported by:
Updated: June 27, 2017
Today on TSR

### Boyfriend slept with someone else

...we were on a break

### Mum says she'll curse me if I don't go to uni

Poll
Useful resources

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE