AQA A2 Biology BIOL5 - 17th June 2015

good stuff. Is there anything like this for unit 4?

Reply 142

LeanneDavis

Has anyone got any useful notes written as they would be for the essay questions? (Can be bullet pointed) On any or all of the main topics that often come up? (Transcription, enzymes, muscle contraction, respiration, DNA technology, Carbon and nitrogen cycle etc.)

Reply 143

anniebk

Variation or biological polymers ..Could be anything

Reply 144

Tplox

When are people going to start past papers?

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Reply 145

lllllllllll

13

Original post by LeanneDavis

Has anyone got any useful notes written as they would be for the essay questions? (Can be bullet pointed) On any or all of the main topics that often come up? (Transcription, enzymes, muscle contraction, respiration, DNA technology, Carbon and nitrogen cycle etc.)

You may find this useful

https://docs.google.com/document/d/1aDMxkJjdMSXu3jx1BcYJPKVg_OcgxiGn4ima9YMKHqA/edit

Bear in mind that it's quite old, the essay titles date back 25 years or so, so not all essay topics would have a chance of coming up in this year's paper. (e.g. pest management)

Reply 146

DCMed96

16

Original post by Tplox

When are people going to start past papers?

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When you realise that you will not meet your offer if you don't start doing papers
(ARGH<<< better start now)

Reply 147

pinkgorilla

5

Hey guys !
Just wondering whether it is necessary to know all topics of as for the essay or are there like just key topics you need to know ?

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Reply 148

johnsangalang

1

Original post by pinkgorilla

Hey guys !
Just wondering whether it is necessary to know all topics of as for the essay or are there like just key topics you need to know ?

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I think the essay focuses on anything across the spec. Just re read your notes and you should be fine. I think the best way to prepare is to look at the previous essay questions and potentially rule them out? But still revise them anyway just in case.

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Reply 149

chatty

8

Original post by lllllllllll

Hi guys, here are my revision notes for unit 5 from last year.

https://docs.google.com/document/d/1VaTttI50YJ934YkIFrxM1pcbcv5f2rcwxpCo6WhEq_g/edit

That's the Unit 5 stuff. It's all the possible question answered in the format of the mark scheme with all the key words included. It should carry the weight of all the questions until the essay question.

At the bottom of the list is a set of extra-curricular knowledge. My friends and I put this together over a period of two months, hope this helps! Best of luck with BIOL5

Thanks a lot. Super detailed notes. :smile:

Reply 150

hey can someone please clarify and tell me if this is correct?
(learning all this on my own, no teacher)

Does indoleactic acid causes plant cells to elongate more?

Can someone also tell me if these stages for tropism is correct?
Stages of tropism
-Cells in the top of shoot produces IAA
-Light causes IAA to move from light side to shaded side of shoot
-Higher concentration of IAA on shaded side
-Shaded side of root elongate more?
-Causes shoot to bend towards light

Thanks :smile:

(edited 8 years ago)

Reply 151

Also, is this correct? (sorry if I am spamming the page)

How Resting Potential is achieved
-Sodium potassium pump actively transports 3Na+ out and 2K+ into axon
-Creates chemical gradient, more positive outside axon
-Sodium ion channel is closed, potassium ion channel is open
-K+ diffuses out of the axon
-Build up of positive ions outside the axon
-equilibrium established, the resting potential is at -65mV

Action Potential
Stimulus stage
-A stimulus causes voltage gated Na+ channels to open

Depolarisation stage
-Na+ diffuses into axon down electrochemical gradient
-Large influx of Na+ ions causes membrane to depolarise
-Action Potential is created when depolarisation up to +40mv is achieved

Repolarisation stage
-At +40mv, voltage gated K+ is open, Na+ channel close
-K+ diffuses out of axon
-Outward diffusion of K+ causes membrane to hyperpolarise

Hyperpolarisation stage
-Hyperpolarisation causes voltage-gated K+ channels to close

Resting potential stage
-Sodium-potassium pump moves 3Na+ out and 2K+ into the axon
-Resting potential re-established.

Reply 152

maarg13

8

Original post by Bustamove

hey can someone please clarify and tell me if this is correct?
(learning all this on my own, no teacher)

Does indoleactic acid causes plant cells to elongate more?

Can someone also tell me if these stages for tropism is correct?
Stages of tropism
-Cells in the top of shoot produces IAA
-Light causes IAA to move from light side to shaded side of shoot
-Higher concentration of IAA on shaded side
-Shaded side of root elongate more?
-Causes shoot to bend towards light

Thanks :smile:

Hi,
IAA is produced in the tips of shoots and roots, causing cells to elongate in the shoot but inhibiting growth in the roots, so has the opposite effect!
Shoots: diffuses from light side to shaded side= stimulates cell elongation= shaded side grows more= bends towards light
Roots: diffuses toward bottom/underside of root= inhibits growth= upper side grows faster/more= bends downwards
Hope this helps :smile:

Reply 153

Original post by maarg13

Hi,
IAA is produced in the tips of shoots and roots, causing cells to elongate in the shoot but inhibiting growth in the roots, so has the opposite effect!
Shoots: diffuses from light side to shaded side= stimulates cell elongation= shaded side grows more= bends towards light
Roots: diffuses toward bottom/underside of root= inhibits growth= upper side grows faster/more= bends downwards
Hope this helps :smile:

LOL, I just re read my post and I realised I made a typo... I was suppose to say "shaded side of shoot", not "shaded side of root"
Sorry... :tongue:

Stages of tropism
-Cells in the top of shoot produces IAA
-Light causes IAA to move from light side to shaded side of shoot
-Higher concentration of IAA on shaded side
-Shaded side of shoot elongate more?
-Causes shoot to bend towards light

so is this correct? sorry about the typo
thanks :smile:

Reply 154

charlottexheath

https://docs.google.com/document/d/1sFYvtqjsr2ebNicV7totM5i5a45MofaF2_QnaVcliQ0/edit

Original post by lllllllllll

Hi guys, here are my revision notes for unit 5 from last year.

https://docs.google.com/document/d/1VaTttI50YJ934YkIFrxM1pcbcv5f2rcwxpCo6WhEq_g/edit

That's the Unit 5 stuff. It's all the possible question answered in the format of the mark scheme with all the key words included. It should carry the weight of all the questions until the essay question.

At the bottom of the list is a set of extra-curricular knowledge. My friends and I put this together over a period of two months, hope this helps! Best of luck with BIOL5

This is sooo helpful!!!!! Do you have anything similar for Unit 4 (or does anyone else?) It would be amazzzing if someone did!!!!

Reply 155

Alicealial

Original post by charlottexheath

This is sooo helpful!!!!! Do you have anything similar for Unit 4 (or does anyone else?) It would be amazzzing if someone did!!!!

THis is amazing if you have it for unit 4 that would be fabbbb!

Reply 156

lllllllllll

13

Original post by Alicealial

THis is amazing if you have it for unit 4 that would be fabbbb!

Yep, it's right here :smile:

Reply 157

Do we need to know about southern blotting for this exam?

Reply 158

charlottexheath

https://docs.google.com/document/d/1sFYvtqjsr2ebNicV7totM5i5a45MofaF2_QnaVcliQ0/edit

Original post by lllllllllll

Yep, it's right here :smile:

This is possibly the most helpful revision source- thankyou!! :smile:

Reply 159