OCR Biology 2015 B1 B2 B3

Original post by pooji11

what did people write for the B1 six marker, with the triplets?

I put child A and B were made by fertilised egg splitting and C was by a second egg being fertilised ( I hope I'm right haha) what did people put for the arrows on the nitrogen cycle??

Reply 22

I wrote that babies A and B were twins (natural clones), which is why they looked alike, as they shared the same genetic information. I also talked about how they were formed.Then for baby C i said that the baby looks different because it has received a different combination of genes, compared to that of babies A and B, 23 chromosomes from both sex cells

Reply 23

courtney1407

I went to my Science teacher after the exam and we went through the question, I got 800% as I did 160 divided by 20 = 8 X l00 = 800. (percentage efficiency is the outcome in april I think it was and it was divided by in income in February), if you've stated the 800% as your answer with your evidence you should still get 1 mark :smile:

Reply 24

Does anyone have any idea what the grade boundaries are usually like? And what is the answer to the nitrogen cycle cause my answer seemed too basic??

Reply 25

zigocarn

Original post by baller_1998

The child inherits the same genes but a different combination of alleles. All the three babies have the same genes, it's just that they have different versions of the same genes and in a different combination.

Reply 26

Its not 800% carnt be. 160-20= 40 (which is the amount it increased by. As you want to find the percentage increase you would have to divide it by 20 and multiply by 100, to see how much it has increased percentage wise. To check if it is correct, you would do: (20*700)/100=140 then 20+140= 160; thats how much its increased by. In the exam i did that and crossed it out because i thought i was wrong, instead i put 87.5

Reply 27

Butterfly233

Who thinks the grade boundaries are going to be low

Reply 28

Did anyone write about ammonia being formed, due to the decay of the plants and animals, for the nitrogen cycle question

Reply 29

Original post by Butterfly233

Who thinks the grade boundaries are going to be low

Fingers crossed haha

But seriously what did yous put for the nitrogen cycle????

Reply 30

Butterfly233

Original post by stressed/student

Fingers crossed haha

But seriously what did yous put for the nitrogen cycle????

I wrote about how animals get the nitrates how the plants absorb the nitrates and why they need it and how decomposes are involved

Reply 31

did you talk about how the plants got the nitrates from the soil? Nitrogen-fixing bacteria..etc.

Reply 32

Original post by stressed/student

I didn't read the question properly and did 800 :frown:

oh well haha! What did people out for the arrows in the nitrogen cycle??

I wrote nothing about Ammonia :s-smilie:

But for soil to plants I spoke about nitrates being used for protein etc
Plants to animals I just spoke about the animals eating plants either directly or from the remnants of the food chain
And finally the decomposition of animals and plants and about detrivores

I absolutely hate the nitrogen cycle though

Reply 33

I put that plant's roots take nitrates from soil, animals eat plants, and death and extortion but I think I was a bit vague

Reply 34

Original post by stressed/student

Who here does triple, so has the horrific 7s to look forward to??

Once the 7s are over, all my exams are done. Just waiting for that day

Reply 35

Original post by baller_1998

did you talk about how the plants got the nitrates from the soil? Nitrogen-fixing bacteria..etc.

I did t but should have, I knew all the words: saprobiotic material, leguminous plants, nitrification, denitrification, nitrogen fixing bacteria, atmospheric nitrogen, de composers, but didn't use many😓

Reply 36

Original post by pooji11

what did people write for the B1 six marker, with the triplets?

I said that two eggs were released during that month and the first egg became twins and the second was fertilised normally
And spoke about the 23 chromosomes in gametes so a different combination therefore they couldn't be identical

Reply 37

Original post by BitofAFangirl

Once the 7s are over, all my exams are done. Just waiting for that day

Well triple science and further maths clash so on my last day of exams I have three hours in the same seat with physics 7 and further maths back to back😭

Reply 38

aaliyakhan

Original post by baller_1998

I said they should measure approx. how much radiation the butterflies may have come in contact with, at different distances from the spill

i wrote the same! as well as the fact that they should check if the butterflies had any previous history in their family genes of having mutations.

Reply 39