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Thank you, youve been very helpful
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A level Biology: Post your doubts here!
- Thread starter XPFMember
- Start date
when reduced NAD releases the electron, it is high in enegry, as it passes from one carrier to the next, it becomes less energetic. This energy which it is loosing is helping to pump out the H+ ions. From what ive learnt no ATP molecules are used during the ETC and chemiosmosis. So i say you reconfirm with your teacher. The first statement is perfectly true.
HorsePower i asked my teacher, he said that a few ATP molecules are used to push out the H+ ions, but that detail is not needed at this level, but we are only supposed to know that the energy comes from the passage of the electron
Asselamun aleykum everyone!!! I have a question about bio a2 paper. As you know in paper 4 there is a section b and in this section thex expect us to write an essay. An generally essays are 9 marks and i m studying from the mark scheme. So my question is if i write 9 points out of 15 points from mark scheme will i get full 9 marks or am i supposed to add things more than the things written in mark scheme? I dont know what to do 
i will give an example: there is this question from 2007 mj q9; describe how a nerve impulse crosses a cholinergic synapse. And this is 9 marks. In the mark scheme the answer has specific 15 points for this question so if i want to get 9 marks am i supposed to write everything in theark scheme? Plss help mee :3 thank you in advance everyone.
i will give an example: there is this question from 2007 mj q9; describe how a nerve impulse crosses a cholinergic synapse. And this is 9 marks. In the mark scheme the answer has specific 15 points for this question so if i want to get 9 marks am i supposed to write everything in theark scheme? Plss help mee :3 thank you in advance everyone.
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okay, thnx
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Can anyone tell me what is the structural differences between smooth ER and Golgi apparatus? I am sooooo confused with the shape of these two.. To be more specific, if they both show up in a microscopic photograph of a cell, how can I distinguish them? Pls help !!! TAT
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They'll probably put vesicles near the Golgi apparatus in the diagram.
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describe the processes that affect allele frequencies in populations with reference to the global distribution of malaria and sickle cell anaemia;
Use sickle cell anaemia as an example to illustrate and discuss how one genotype may be fitter than another when a particular environmental factor (infection with Plasmodium) is exerting a strong selection pressure
pleeeease?
Use sickle cell anaemia as an example to illustrate and discuss how one genotype may be fitter than another when a particular environmental factor (infection with Plasmodium) is exerting a strong selection pressure
pleeeease?
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Yes. Golgi and Smooth ER does actually look quite similar. But there are a few tips with which you can easily distinguish them.
1) Golgi produces lysosomes or vesicles. Youll see these circular vesicles around the golgi or maybe even pinching off from it or fusing into it. There would not be any such vesicles around the smooth ER.
2) There is always only 1 Golgi per cell. It either had one, or doesn't have it. Smooth ER can be various in number.
It really isn't that difficult because the lysosomes are your key. And if you don't see lysosomes and multiple similar structures its not a Golgi.
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Can anybody please give me the proper definitions of; Habitat, Community, Ecosystem and Niche?
I can't express myself clearly enough :/
I can't express myself clearly enough :/
AOA,
Please spare few minutes and go to this thread http://www.xtremepapers.com/community/threads/dua-for-all-candidates.14272/ and make dua for all those currently appearing in the exams. You will also find useful duas in it and Remember every share counts.
Please spare few minutes and go to this thread http://www.xtremepapers.com/community/threads/dua-for-all-candidates.14272/ and make dua for all those currently appearing in the exams. You will also find useful duas in it and Remember every share counts.
If you mention any 9 points out of the 15, then you'll get the full mark. But those 9 points must be mentioned in a logical order.Asselamun aleykum everyone!!! I have a question about bio a2 paper. As you know in paper 4 there is a section b and in this section thex expect us to write an essay. An generally essays are 9 marks and i m studying from the mark scheme. So my question is if i write 9 points out of 15 points from mark scheme will i get full 9 marks or am i supposed to add things more than the things written in mark scheme? I dont know what to do
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They're all here..
http://papers.xtremepapers.com/CIE/...A and AS Level/Biology (9700)/9700_y13_sy.pdf
Look for definitions section.
Isnt sucrose water soluble? :/ Ive read that all sugars are water soluble..oh srry my bad... i didnt read it properly
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yes they are
..... i just rechecked glucose is only converted to sucrose only for the fact that , sucrose is more complex (disaccharide) and less reactive than glucose
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There are protiens, (channel, transfer), there are cholesterol molecules, there are Glycolipids and Glycoprotiens as well. And of course the rest is the Phospholipid Bilayer.heproteins: 509119 said:
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If it says ignore, the examiner will 'ignore' your error and continue reading your point and mark it based on other facts mentioned.
If it says reject, the examiner will reject the entire point you mentioned.
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Meri post like karne pe maut ati hai begharaton?