A2 Edexcel Unit 5 Bio exam discussion (31 Jan 2012)
Biology exam discussion - share revision tips in preparation for GCSE, A Level and other biology exams and discuss how they went afterwards.
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Re: A2 Edexcel Unit 5 Bio exam discussion (31 Jan 2012)
Here's a website to familiarise yourself withe DBS.
http://www.edheads.org/activities/brain_stimulation/
Adice form my teacher: Read the artilce many times over till you know it like the back of yr hand. You won't have time to look for things in the exam. -
Re: A2 Edexcel Unit 5 Bio exam discussion (31 Jan 2012)THANKS A TON!! Just what i was looking for(Original post by farhanyen)
questions:
ethical issues of DBS?
why/how does parkinsons cause tremors and involuntary movement?
list shortcomings of levedopa and drug-telated treartment?
advantages of DBS over other treatments?
describe and explain side effects of DBS?
Explain ( in short detail) how DBS works to traet brain disorders?
Explain why DBS can be used to treat a multitude of disorders?
Check yr textbooks/guide bks ask yr teachers etc abt these qs. Try to get the best possible answers. Then we'll post and discuss them here.
Anything aym3n?
Please post any notes you have on parkinson's, dopamine,blood brain barrier and all that stuff or any important relevant things that you know abt this stuff.
I've searched and found some notes that a based on the specification, for both topic 8 and 7 as this thread as for the whole of unit 5. Warning, do not study from these notes alone, as specification is more like a checklist. Study the textbook and rev guide really well though.
Note: I had to download a pdf splitter just to upload these so PLEASE upload whatever you have thx.
Good luck all!!!!! A*s for everyone!!!!

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Re: A2 Edexcel Unit 5 Bio exam discussion (31 Jan 2012)
Feel free to add/change/tell me its wrong! Am only guessing, and thanks to farhenyan for questions
questions:
ethical issues of DBS?
Can worsen conditions of diseases if not placed in the right area of brain, not 100% guaranteed to work, costly?, only available to patients with severe conditions.
why/how does parkinsons cause tremors and involuntary movement?
Parkinsons disease results in death of dopamine secreting neurones in the basal ganglia, which normally release dopamine in motor cortex. Therefore the motor cortexes are not able to recieve dopamine which leads to loss of control of movement and tremors.
list shortcomings of levedopa and drug-telated treartment?
advantages of DBS over other treatments?
Do not have to take tablets, can be calibrated for optimum results
describe and explain side effects of DBS?
apathy (emotions become supressed), hallucinations, compulsive gambling,
hypersexuality, cognitive dysfunction (loss of intellectual functions), and depression (I assume it disrupts Serotonin levels?)
Explain ( in short detail) how DBS works to traet brain disorders?
DBS sends high frequency electrical impulses to specific areas to interfere with brain activity (passing of impulses through motor neurones) and regain some control.
Explain why DBS can be used to treat a multitude of disorders?
The lead for DBS can be placed at different areas of brain according to different symptoms -
Re: A2 Edexcel Unit 5 Bio exam discussion (31 Jan 2012)
Hey guys, I've also come up with some questions!

These are for DBS:
How does DBS “Change brain activity?”
What is meant by its “reversible”?
What is a “blinded study”?
Complications and side effects?
Why is battery encased in Titanium?
What is the VIM in thalamus, globus pallidus and subthalmic nucleus responsible for?
For Depression:
What is meant by “black cloud lifting”?
Tourettes:
"Those with severe personality disorders and substance abuse problems should be excluded.” Why?
Dystonia:
How does botox stabilise symptoms?
Brain Imaging:
Describe how fMRI works.
The biology I think we need to know inside out is the functions of each area, effect of drugs/chemical imbalances and muscles cos I think I saw something about muscles in article. Please do post replies to compare and stuff. GOOD LUCK EVERYONE!!!
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Re: A2 Edexcel Unit 5 Bio exam discussion (31 Jan 2012)Thank you !!!!!!!!(Original post by farhanyen)
questions:
ethical issues of DBS?
why/how does parkinsons cause tremors and involuntary movement?
list shortcomings of levedopa and drug-telated treartment?
advantages of DBS over other treatments?
describe and explain side effects of DBS?
Explain ( in short detail) how DBS works to traet brain disorders?
Explain why DBS can be used to treat a multitude of disorders?
Check yr textbooks/guide bks ask yr teachers etc abt these qs. Try to get the best possible answers. Then we'll post and discuss them here.
Anything aym3n?
Please post any notes you have on parkinson's, dopamine,blood brain barrier and all that stuff or any important relevant things that you know abt this stuff.
I've searched and found some notes that a based on the specification, for both topic 8 and 7 as this thread as for the whole of unit 5. Warning, do not study from these notes alone, as specification is more like a checklist. Study the textbook and rev guide really well though.
Note: I had to download a pdf splitter just to upload these so PLEASE upload whatever you have thx.
Good luck all!!!!! A*s for everyone!!!!

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Re: A2 Edexcel Unit 5 Bio exam discussion (31 Jan 2012)These are the answers I came up with. Will try to answer the questions after I have found the answer(Original post by G.Kaur)
Hey guys, I've also come up with some questions!
Dystonia:
How does botox stabilise symptoms?
the botox temporarily prevents movements of muscles to prevent or reduce the ability of muscle to contract and spasm.
Brain Imaging:
Describe how fMRI works.
fMRI monitors the uptake of oxygen in different brain areas. Deoxyhaemoglobin absorbs the radoi wave signal and later re-emits it, while oxyhaemoglobin does not. when an area of the brain is active, the blood flow to the area increases and more oxyhaemoglobin is delivered to supply the active cells with oxygen that they need for aerobic respiration. Hence, less signal is absorbed.
The biology I think we need to know inside out is the functions of each area, effect of drugs/chemical imbalances and muscles cos I think I saw something about muscles in article. Please do post replies to compare and stuff. GOOD LUCK EVERYONE!!!
any mistakes , quote me
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Re: A2 Edexcel Unit 5 Bio exam discussion (31 Jan 2012)
My answers:
list shortcomings of levedopa and drug-telated treartment?
1)A tenth of patients do not respond to this drug.(paragraph 10)
2)Eventually becomes less effective as brain cells continue to die off
why/how does parkinsons cause tremors and involuntary movement?
Parkinsons disease results in death of dopamine secreting neurones in the basal ganglia, which normally release dopamine in motor cortex. Therefore the motor cortexes are not able to recieve dopamine which leads to loss of control of movement. This results in involuntary contraction of muscles and tremors.
ethical issues of DBS?(cost is not ethical issue its under disadvantages of DBS
)
1)Underlying priciples behinf DBS are not clear, hence may not be effective
2)Very risky and can cause serious complication
3)very invasive treatment
Explain why DBS can be used to treat a multitude of disorders?
Diffferent brain disorders caused by different parts of the brain.DBS electrode may be placed at a specific part of the brain to treat a specific disorder.
Disadvantages of DBS?
1)Side effects
2)Cost, not everyone can afford it
Advantage of DBS over drug-related treatment?
1)DBS is targeted treatment
2)Noneed to constantly take tablets
3)Very effective mostly
4)Can be calibrated to optimum results
Why is DBS reversible?
1)Because electrodes can be taken out. -
Re: A2 Edexcel Unit 5 Bio exam discussion (31 Jan 2012)
More qs
Explain how 2 drugs used to treat DBS work.
Explain how fMRI, MRI, CT scan work.( always comes out )
Differences between CT scan MRI?
State 1 difference and similarity between Parkinson's and depression?
Explain how SSRI's work and explain how estascy work.
Suggest why deep brain stimulation has been approved for many brain disorders(see Paragraph 2) when its underlying principles are not clear? -
Re: A2 Edexcel Unit 5 Bio exam discussion (31 Jan 2012)under the subtitle ' Dystonia' point no. 30 , 2nd line(Original post by farhanyen)
Botox? Please tell me where in the article mantions botox. thx -
Re: A2 Edexcel Unit 5 Bio exam discussion (31 Jan 2012)page 6(Original post by farhanyen)
Botox? Please tell me where in the article mantions botox. thx
under the subtitle ' Dystonia' point no. 30 , 2nd line -
Re: A2 Edexcel Unit 5 Bio exam discussion (31 Jan 2012)Thanks you so much i think these questions are in good standared. so it will be use full for the people who are doing this exam(Original post by farhanyen)
My answers:
list shortcomings of levedopa and drug-telated treartment?
1)A tenth of patients do not respond to this drug.(paragraph 10)
2)Eventually becomes less effective as brain cells continue to die off
why/how does parkinsons cause tremors and involuntary movement?
Parkinsons disease results in death of dopamine secreting neurones in the basal ganglia, which normally release dopamine in motor cortex. Therefore the motor cortexes are not able to recieve dopamine which leads to loss of control of movement. This results in involuntary contraction of muscles and tremors.
ethical issues of DBS?(cost is not ethical issue its under disadvantages of DBS
)
1)Underlying priciples behinf DBS are not clear, hence may not be effective
2)Very risky and can cause serious complication
3)very invasive treatment
Explain why DBS can be used to treat a multitude of disorders?
Diffferent brain disorders caused by different parts of the brain.DBS electrode may be placed at a specific part of the brain to treat a specific disorder.
Disadvantages of DBS?
1)Side effects
2)Cost, not everyone can afford it
Advantage of DBS over drug-related treatment?
1)DBS is targeted treatment
2)Noneed to constantly take tablets
3)Very effective mostly
4)Can be calibrated to optimum results
Why is DBS reversible?
1)Because electrodes can be taken out. -
Re: A2 Edexcel Unit 5 Bio exam discussion (31 Jan 2012)energy gained from krebs cycle forces the H+ ions inside the intermembranous space of mitochodria, when they want to come inside the matrix to stabilise the gradient they pass through pore protiens called ATP SYNTHASE this then generates the bulk of ATP ! thats chemiosmosis !(Original post by ghogho)
hey! i truley need help!! could anyone explain for me what is ment by Chemiosmosis it came in unit 4 exam and now it is poping again in some revsion notes!!!!
thx in advance
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Re: A2 Edexcel Unit 5 Bio exam discussion (31 Jan 2012)thx u sooooo much(Original post by ih8edexcel!)
energy gained from krebs cycle forces the H+ ions inside the intermembranous space of mitochodria, when they want to come inside the matrix to stabilise the gradient they pass through pore protiens called ATP SYNTHASE this then generates the bulk of ATP ! thats chemiosmosis !
gd luck & wish we all get A* 
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Re: A2 Edexcel Unit 5 Bio exam discussion (31 Jan 2012)
Of you guys look at the wikipedia article for DBS, at http://en.wikipedia.org/wiki/Deep_brain_stimulation you'll see that they've copied the article word for word.
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Re: A2 Edexcel Unit 5 Bio exam discussion (31 Jan 2012)or maybe the other way round Haha X(Original post by aneziri20)
Of you guys look at the wikipedia article for DBS, at http://en.wikipedia.org/wiki/Deep_brain_stimulation you'll see that they've copied the article word for word.
