AQA A2 BIOL5 22nd June 2012

There isn't much point in marking the essays you write, just make sure you can write a lot and cover a lot of different points. I wouldn't know how examiners actually mark the essays, they go to many standardisation meetings where they discuss marking. Generally, the first thing they look at is the length of the essay.

Yes I agree, you need to have both breath and depth, expect to spend about 30 minutes on the essay, you may get more time in the exam...
I was taught to have a introduction and conclusion obviously and have 4/5 different topics to write about with a good paragraph on each. Therefore you cover both depth and breath

Reply 861

dc2012

Original post by clairelouise444

Thanks

Do you think they are likely to repeat topics theyve done before?
and if i was doing a variation essay and wanted to include "extra reading" info for more marks, could i talk about something like the variation between humans and animals in terms of distribution of layers in the eye?

I think it will be highly unlikely that they will put in an essay question that has prieviously been in an exam paper, i.e. they probably wont ask you to explain about cycles in biology. And yeah i think you could gain marks in that as long as its relevant to the question.

Reply 862

xXACEXx

I don't mind an essay on: structure of proteins and their functions, ATP how its produced and used, inorganic ions, variation, enzymes.

Reply 863

NutterFrutter

Original post by xXACEXx

I don't mind an essay on: structure of proteins and their functions, ATP how its produced and used, inorganic ions, variation, enzymes.

Those would all be great essays. :biggrin:

Reply 864

xXACEXx

Original post by NutterFrutter

Those would all be great essays. :biggrin:

Yh really hoping for one of them at least. You can write quite a lot about them and they cover units 1-5 as well.
Also questions about proteins or enzymes even ATP interlink a bit.

Reply 865

JJMick

9

Original post by handsome7654

Doesn't temporal summation occurs with cones??

No, rods because many rod cells can be connected to one neurone, so the potentials of each can be combined to reach the threshold, so therefore rods are used at night time.

Reply 866

JJMick

9

I really hope the one for proteins comes up, I have something that I can add from extra reading :smile:

Reply 867

dc2012

Could someone please explain to me the answer to question 5cii on the JUNE 2011 paper

" sicentists need to take precautions when they carry out restriction mapping. They need to make sure that the enzyme they have used has completely digested the DNA. One check they may carry out is to add the sizes of the fragments together. How could scientists use this information to show that the DNA has not been completely digested? Explain your answer.

Thanks

Reply 868

handsome7654

Original post by JJMick

No, rods because many rod cells can be connected to one neurone, so the potentials of each can be combined to reach the threshold, so therefore rods are used at night time.

No I mean doesn't temporal summation occurs for cones??

Reply 869

Bluewinds

Original post by JJMick

No, rods because many rod cells can be connected to one neurone, so the potentials of each can be combined to reach the threshold, so therefore rods are used at night time.

Isn't that Spatial summation? Temporal is repeated impulses through one neurone while Spatial is several neurones providing impulses.

Reply 870

Erotas

Original post by Rizzy J

Didn't write them, found them on the net

Hey, are there any notes like this for unit 1? Thanks

Reply 871

Pritesh.Mistry

In a Unit 5 paper what seems to come up more? Genetics, or all the other topics like nerves/muscles/homeostasis etc.?

Reply 872

drlesliechoi

Original post by Pritesh.Mistry

In a Unit 5 paper what seems to come up more? Genetics, or all the other topics like nerves/muscles/homeostasis etc.?

10 questions, 1 will be essay and 1 will be a data analysis/HSW question, so 8 questions on 8 chapters, assume there is 1 for each although that is not always the case

Reply 873

Erotas

I think I've finished my Unit 5 revision. I'm not too late to be starting my synoptic revision now am I? Do I have enough time from now to revise units 1, 2 and 4, practice essays and do past papers?

Reply 874

drlesliechoi

Original post by Erotas

I think I've finished my Unit 5 revision. I'm not too late to be starting my synoptic revision now am I? Do I have enough time from now to revise units 1, 2 and 4, practice essays and do past papers?

Honestly yes, you would be surprised how much is still at the back of your head and it is really not necessary to know every single topic back to front, you should learn topics across the whole syllabus in categories, it helps to just do the essays open book as you refresh yourself on certain topics...

Try and aim for 2 essays a day from tomorrow and you should be fine, its what I did for my essay revision

Reply 875

Granger

im going to try and do a plan and an essay a day, with a bit of topic 5 revision. When i got my marks back from previous essays i got like 16-19 every time, it feels really harsh how you only get like 1 or two marks for a whole paragraph.

Reply 876

dc2012

Guys just want to clarify an answer. In the nelson thornes book, question 2a for chapter 14 exam style questions. it shows two anticodons(tRNA) AGC UUC and then asks for the sequence of bases found along the corresponding section of the coding DNA strand. The answer i put was TCG and AAG. However the answer on thomas reddington website is AGC TTC. I think this may be wrong because if you think about it and go along with my answer it seems correct >>>>>>>>>> TCG AAG is the two sequence of bases on the DNA CODING STRAND therefore the template strand which is the strand in which RNA polymerase binds to transcribe the gene will be AGC and TTC>>>>>>> the mRNA codons will be UCG and AAG therefore the anticodons will be AGC and UUC.

Can anyone understand where im coming from, and is the mark scheme wrong???????????

Reply 877

Bugsy

1

Original post by dc2012

Guys just want to clarify an answer. In the nelson thornes book, question 2a for chapter 14 exam style questions. it shows two anticodons(tRNA) AGC UUC and then asks for the sequence of bases found along the corresponding section of the coding DNA strand. The answer i put was TCG and AAG. However the answer on thomas reddington website is AGC TTC. I think this may be wrong because if you think about it and go along with my answer it seems correct >>>>>>>>>> TCG AAG is the two sequence of bases on the DNA CODING STRAND therefore the template strand which is the strand in which RNA polymerase binds to transcribe the gene will be AGC and TTC>>>>>>> the mRNA codons will be UCG and AAG therefore the anticodons will be AGC and UUC.

Can anyone understand where im coming from, and is the mark scheme wrong???????????

The anti codons are AGC UUC. They are complementary to the mRNA sequence which would be UCG AAG right? Now mRNA sequence is complementary to the DNA sequence, except the fact that uracil is not present, instead it's thymine. So if we go complementary again you would get AGC and TTC. So in actual fact the DNA sequence and tRNA sequence are the same EXCEPT for the uracil/thymine changes. Hope that makes sense :smile:

Reply 878

masterhr1

5

Does anyone know which papers from the old spec match up with the content in BIOL5??