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AQA BIOL5 Biology Unit 5 Exam - 22nd June 2011

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Really struggling with this unit :/
What revision methods is everyone using? What works best for you...revision guides, textbooks, online resources?
Also this sounds a bit weird but is there anyway how you can improve application skills for hsw and making links other than doing past papers? There's only a few.

I make notes from the Nelson Thornes and CGP books, then do every question I can get my hands on to do with the topic. So I do the NT exam questions, the CGP questions and the past paper questions. I've been doing homeostasis all day and I feel like crying.

Reply 601

FristyKino

Can someone please explain to me what mRNA is?

Reply 602

User544981

Original post by FristyKino

The wolf question on june10 is a major wtf -.-

agreee with u 100 percent if i had rep i wud rep u mate
hate aqa all the maths exams especially

Reply 603

User544981

if both the synoptic essays are based on genetics im doomed
hate genetics theres so much to learn

Reply 604

jamest92

Original post by FristyKino

Can someone please explain to me what mRNA is?

Basically mRNA is a way of transporting the genetic code for proteins from DNA in the nucleus to ribosomes in the cytoplasm where the protein chain is created.
Hope that helps.

Reply 605

choc1234

howmuch synoptic revision has everyone done?
has everyone learnt everything from AS in detail?
bit worried :s-smilie:

Reply 606

User12399

Original post by choc1234

howmuch synoptic revision has everyone done?
has everyone learnt everything from AS in detail?
bit worried :s-smilie:

its not about detail. breadth not depth.

Reply 607

kingsmod1

does any1 have any ideas how to do practice Qs on bio apart from past paper and specimen?

many thanks guys x

Reply 608

AboutAn8orA9

Original post by kingsmod1

does any1 have any ideas how to do practice Qs on bio apart from past paper and specimen?

many thanks guys x

The exam style questions at the end of each topic are pretty useful. Also questions in the CGP book if you have it?

Reply 609

arvin_infinity

Original post by AboutAn8orA9

The exam style questions at the end of each topic are pretty useful. Also questions in the CGP book if you have it?

Is generator potential and nerve impulse are the same? a bit confused

Reply 610

l4ith

Original post by FristyKino

Can someone please explain to me what mRNA is?

mRNA (messenger RNA) is a messenger molecule containing complementary base pairs to a DNA template strand. It is used to transport genetic information OUT of the nucleus to the machinery needed in protein synthesis (in the cytoplasm). It is created because DNA is way too big to exit the nucleus, so a smaller molecule is needed.

It is a type of ribonucleic acid so it contains a) a ribose sugar (rather than deoxyribose in DNA) and b) replaces the base 'thymine' T with 'uracil' U.

It is suited to its function because it produces an exact complementary sequence to the DNA template strand, meaning it codes for amino acids and hence polypeptides with high accuracy. It is also relatively unstable, meaning after it has been used it is broken down preventing excess protein being produced.

Reply 611

l4ith

Original post by arvin_infinity

Is generator potential and nerve impulse are the same? a bit confused

A generator potential is what is created in receptors and is a direct result of a stimulus. If the generator potential (the change in p.d. caused by a stimulus) exceeds a THRESHOLD (the minimum p.d. needed to cause an impulse) then an NERVE IMPULSE (passage of an action potential in a neurone) is created. At least this is what I understand it to be, the terminology is kinda vague.

Reply 612

l4ith

Original post by Flux_Pav

suggest why somatic cell therapy more successful in treating diseases caused by a recessive allele than those caused by a dominant allele (2 marks)

Most likely because if the disease is caused by recessive alleles, only ONE of the alleles (from the mother's and father's chromosomes) would need to be replaced (gene replacement) or supplemented (gene supplementation) with a dominant healthy gene. If it is a dominant allele causing the disease, the healthy gene would be recessive so there is a chance that two healthy genes would have to be inserted, which is much more difficult when using gene therapy via somatic cells.

Reply 613

Flux_Pav

Original post by l4ith

thanks

and also for the latter, inserting two healthy recessive genes will only work by gene replacement rather than supplementation right? because recessive alleles cannot mask the effects of the dominant alleles

Reply 614

xelaman

Correct

Inserting a functional gene (with recessive alleles) does not remove the defective gene (with dominant alleles) - it just means that the cells produce both functional and non-functional proteins at the same time :smile:

Reply 615

Ineluctable

I'm fine with everything including synoptic essays, except gene technology. Our teacher had to rush the course towards the end, so I'm learning, as opposed to revising

Reply 616

tehsponge

Original post by Ineluctable

I'm fine with everything including synoptic essays, except gene technology. Our teacher had to rush the course towards the end, so I'm learning, as opposed to revising

Jealous. How did you get comfortable with the synoptic essays?

Reply 617

Ineluctable

Original post by tehsponge

Jealous. How did you get comfortable with the synoptic essays?

They aren't hard. Just look over the specifications of the other units. You don't have to know anything in great detail, just pick the relevant points.

Reply 618

kingsmod1

guys, i think im gonna get BBB at A level wid bio chem and maths (strted wid DDD)

i have always wanted an A and i feel these grades are terrible at A level just for myself

do u lot think its that bad

p.s. bio 5 is makin gd progress :P

Reply 619

tehsponge

Original post by Ineluctable

They aren't hard. Just look over the specifications of the other units. You don't have to know anything in great detail, just pick the relevant points.

I thought they had to be as detailed as the 6 mark questions you get at the end of the unit 4 paper? I've always thought of them as like 3/4 of those questions. Also I can't remember much from unit 2 because I found it so mind numbingly boring.