AQA BIOL5 Biology Unit 5 Exam - 22nd June 2011

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Reply 200

angel1992

also can genes isolated by restriction endonucleases be cloned by pcr, if so how?

Reply 201

tehsponge

Original post by angel1992

hey i have a question about chapter 16 which is one long chapter
anyway, dna that is produced by reverse transcriptase, how is this dna that isolated inserted into a vector. I know the dna isolated by restiction endonucleases can inserted into a vector because its done using the same restriction endonucleases from which it was produced. However dna isolated by reverse transcriptase wasnt isolated in this way so how is it inserted into a vector if insertion involves restriction endonucleases?? :s

I don't really understand your question, but the desired gene is removed from the DNA using restriction endonuclease and then the same RE is used to remove a gene in the plasmid, allowing the desired gene to be inserted using DNA ligase.
Oh okay I understand it now. When you use reverse transcriptase to produce DNA fragments, you don't insert them into a plasmid (it doesn't mention them in the AQA endorsed textbook at least).

(edited 12 years ago)

Reply 202

angel1992

Original post by tehsponge

Yeah...I would have mentioned them both, as they both could be the cause of the cancer... Maybe check the examiners report?

i think its because if you mutate oncogenes which speed up cell divsion massively hence cause cancer then you would be stopping cell division. but then again i see your point becauseit could be protoncogenes you mutate and if you mutate proto oncogenes then onco genes are formed which increase cell division rapidly

maybe mark scheme is wrong?

Reply 203

angel1992

Original post by tehsponge

What is the DNA/gene? Really need the rest of the question to help.

I read th examiners report an i think in the mark scheme it means ignore that oncogenes in that ignore reference to mutations of oncogenes as that would stop cell division and not give cancer, but if you put proto oncogenes being mutated you would get oncogenes and this would cause cander so you get the mark

Reply 204

angel1992

is PCR genetic engineering, i read that the deifintion of GE is the transfer of genes from one organism to another, while pcr is the replication of genes over and over again? so it cant be GE?

Reply 205

Star12345678910

Original post by INeedToRevise

BIOL5 Past paper questions with markschemes
http://www.mediafire.com/file/ynzizznywym/Unit%205%20-%20Biology.rar

hey confused ..? d/l it but the file wont open. any ideas how i can get it to open.....?

Reply 206

angel1992

Original post by student777

I was thinking the I bands, H zones etc... never mind :tongue:

Use restriction endonucleases to cut up a desired gene and insert it into a plasmid. Then insert the plasmids into bacteria. Use marker genes (antibiotic resistance, fluorescent proteins etc) to identify which bacteria have the desired gere.

That's one method... I really need to read up on this xD

For other people: Briefly describe what happens to proteins on the cell membrane during an action potential.

whats the other method because you do have reverse transcriptase being isolated but how is that used in recombinant genes???!!

Reply 207

INeedToRevise

Original post by Star12345678910

hey confused ..? d/l it but the file wont open. any ideas how i can get it to open.....?

Its a rar file so you have to extract it using winrar. Download winrar if you don't have it and locate the file and extract it.

Reply 208

INeedToRevise

Is anyone planning on doing the essay question first?

Reply 209

coffee345

has anyone got any ideas what the synoptic essay could possibly be on?

Reply 210

Star12345678910

Original post by INeedToRevise

Its a rar file so you have to extract it using winrar. Download winrar if you don't have it and locate the file and extract it.

thanks for that d/l winrar and it worked. i now hav millions of biol5 questions with answers yay. taa !!

Reply 211

TheAwkwardBalloon0

Original post by Stirlo

There's a book somewhere, sorry I cant remember what it's called my schools ordered our class some, which contains 20 essay questions and ideal model answers.

On a side note for the synoptic section you only get 16 marks for content, the other 9 marks come from spelling/grammar, ensuring you use multiple chapters and subsections etc

I think the book is by someone called Dr Robert Mitchell and it's awesome its got a frog on the front; just type the author name into amazon and it should come up. It only costs like £6.99 and its sooo worth it.

Reply 212

Stirlo

Original post by TheAwkwardBalloon0

Yeh that's the one :smile:

Reply 213

INeedToRevise

Original post by Star12345678910

thanks for that d/l winrar and it worked. i now hav millions of biol5 questions with answers yay. taa !!

No problem :smile:

Reply 214

Calimboness

Original post by INeedToRevise

Is anyone planning on doing the essay question first?

What my teacher said to do is:

1. Go straight to the essay question
2. Decide which question you will answer
3. Brainstorm any ideas you can think of straight off
4. Go back and start doing the res of the paper in your normal method
5. Things will likely keep popping into your head about the essay. Write down any ideas as you go through the rest of the paper
6. When you get to the essay page after finishing the rest of the paper, order the notes you made into a logical order and write the essay, because by then you've been thinking about the essay all the way through so you'll be "in the zone"

That's what I'm going to do :smile:

Reply 215

TlanTlan

Original post by Calimboness

Yeah i heard this too, too bad there aren't many unit 5 past papers to practice this on :frown:

Reply 216

Calimboness

Original post by TlanTlan

Yeah i heard this too, too bad there aren't many unit 5 past papers to practice this on :frown:

I agreee. We did last year's paper as a mock but there wasn't enough lesson time to do it in one stretch like we would for the real thing: we did the first section in one lesson and the essay section in another, so there was no chance for me to test if this theory works. Guess we'll just have to see on the day :s-smilie:

not an ideal situation.

Reply 217

Seasick Steve

Original post by INeedToRevise

Is anyone planning on doing the essay question first?

I was going to, but probably won't in the end because if neither of the questions are very appealing, then it might throw me off-track when it comes to the rest of the paper, which let's be honest is worth about 3/4 of the total marks on offer.

Reply 218

TlanTlan

Read essay first and do a quick brainstorm to get ideas flowing, then as you're going through the actual unit 5 stuff more things will pop into your head which will get you more marks than if you'd just dived into it.