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AQA BIOL5 Biology Unit 5 Exam - 22nd June 2011

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My stomach literally just dropped below my feet when I saw people talking about writing a synoptic essay..then i realised this was AQA and i'm edexcel phew!

Reply 521

emmaaa65

Original post by salman s

I think this is a pretty good essay, you get in a lot of knowledge and you'd probably get the relevance, breadth and quality of language marks. I'd say its 14/15 for the knowledge, maybe just add something about oestrogen receptors forming the transcription initiation complex to link receptors to DNA. Otherwise it's really good :smile:

It's one of those questions where all the knowledge is from like only 1 unit.

thankyou so much for taking the time to look over it! i tried doing a question that was too broad so it would challenge me soo yeah its good to know that its alright!
thanks again! :smile:

Reply 522

salman s

Original post by emmaaa65

thankyou so much for taking the time to look over it! i tried doing a question that was too broad so it would challenge me soo yeah its good to know that its alright!
thanks again! :smile:

No problem, I.v been going through the synoptic essays myself :smile:

really hoping for something on proteins/cell membrane/ ATP or Negative feedback. If both the options are something to do with Ecology or Nutrient Cycles, then things will not go well :s

Reply 523

salman s

Original post by student777

I like your sig :tongue:

Thanks i like it too :biggrin:

Reply 524

emmaaa65

Original post by salman s

No problem, I.v been going through the synoptic essays myself :smile:

really hoping for something on proteins/cell membrane/ ATP or Negative feedback. If both the options are something to do with Ecology or Nutrient Cycles, then things will not go well :s

same! if anything comes up on proteins or enzymes i will be so happy! aha

Reply 525

TlanTlan

Original post by tehsponge

you made a Bio funny.
Yeah I hate the menstrual cycle and blood glucose level control stuff as well.

I was hoping someone would pick up on that :colondollar:

Reply 526

vickidougal

can anyone explain restriction mapping and DNA sequencing?

really don't recall ever being taught that :frown:

panic!

Reply 527

Destroyviruses

Original post by vickidougal

can anyone explain restriction mapping and DNA sequencing?

really don't recall ever being taught that :frown:

panic!

http://www.thestudentroom.co.uk/showthread.php?p=31886619#post31886619

On that page. Parallal has posted notes, they are very useful.

Reply 528

KingMessi

Original post by vickidougal

can anyone explain restriction mapping and DNA sequencing?

really don't recall ever being taught that :frown:

panic!

Restriction mapping-often the genome is too big to be initially sequenced using a DNA probe and then separated, so restriction mapping is used to separate the genome into shorter sequences. The genome is cut using enzymes called restriction endonucleases that cut at specific recognition sites that have specific bases that give the DNA of that site a structure complementary to the active site. This cuts the genome into smaller sequences, and then the different-sized fragments are separated using gel electrophoresis.

Restriction mapping then involves using different pairs of restriction endonucleases to sequence the fragments; by using these different pairs of endonucleases and looking at where they cut on the genome, the plasmid's genome, or organism's genome, can be put back together...

Hope that helps!

Reply 529

KingMessi

Original post by vickidougal

can anyone explain restriction mapping and DNA sequencing?

really don't recall ever being taught that :frown:

panic!

DNA sequencing:

-The first stage is to set up four test tubes, including the DNA fragments to be sequenced, terminator nucleotides containing each of the four nucleotide bases, DNA polymerase to catalyse DNA synthesis and primers. Each test tube contains each of the four nucleotide bases.
-Terminator nucleotides can attach to the initial DNA strand using DNA polymerase. The binding of nucleotides in the pool is a random process, and so the binding of a terminator nucleotide or a normal nucleotide is equally likely, and therefore the termination of DNA synthesis could be after either a few bases or a lot of bases. However, all the fragments in one tube will end in the base in that test tube-for example, adenine for tube 1, guanine for tube 2 etc.
-These bases/fragments can be identified due to the presence of primers, because the primer has a complementary base to the DNA fragments; and it has been either radioactively labelled or florescently labelled.

-The fragments are then separated using a technique called gel electrophoresis. This involves placing the fragments onto an agar gel and passing a voltage across it. Because the gel is resistant, smaller fragments will move further than larger fragments over a period of time, and therefore the distance moved by the fragments can be used to decipher the size of the fragments.

Again, off the top of my head...

Reply 530

Tericon

Original post by hahaff

i hate the fact that there is only one paper to learn from

Two. Specimen paper.

Reply 531

WillHilliam

thought i should post this on here and hope somebody finds it useful

http://biology5revision.webs.com/

i got a bit bored.

Reply 532

User544981

Original post by Tericon

Two. Specimen paper.

yep thats true but the spec paper doesnt truly show what the real papers are like tbh but yeah 2 papers

Reply 533

Y.D

Original post by hahaff

yep thats true but the spec paper doesnt truly show what the real papers are like tbh but yeah 2 papers

Like we're ever going to know what the papers gonna be like with AQA :rolleyes:

Reply 534

RyuHADOUKEN

Original post by Y.D

Like we're ever going to know what the papers gonna be like with AQA :rolleyes:

^ THIS!

Reply 535

User544981

Original post by Y.D

Like we're ever going to know what the papers gonna be like with AQA :rolleyes:

yep that is also true
aqa spec papers are nothing like the real thing hoping theres not to much hsw on this paper but there probs will be

Reply 536

Jin3011

Original post by hahaff

yep that is also true
aqa spec papers are nothing like the real thing hoping theres not to much hsw on this paper but there probs will be

That aqa spec paper is literally so bad. I mean, how are we ever expected to know how to do that restriction mapping question :confused:

Reply 537

Sly Racoon

Don't know if anyone has put a link to these already, a bit long but seem pretty good:

http://www.studentcreche.co.uk/resources/biol5.pdf

Reply 538

M.A.

Original post by Jin3011

That aqa spec paper is literally so bad. I mean, how are we ever expected to know how to do that restriction mapping question :confused:

just done the paper and that question was like :eek:

...
thank god it's not just me :smile:

Reply 539

Jin3011

Original post by M.A.

just done the paper and that question was like :eek:

...
thank god it's not just me :smile:

Yeah I was thinking the same. AQA just love their random animals though, so I think we should expect to see a female african spotted cane toad and others alike. :frown: