Biology help

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sammy2012

Hi,

I do AQA biology. This is a new spec. I'm predicted an A*.... I struggle with the comprehension questions, and essay and practical questions (this is all on my paper 3- no ISA/EMPA anymore).

Do you have of your revision sources left etc? Anything would help :smile:

Reply 281

sammy2012

Original post by Bluebird38

Hi, hope you're doing well in your Medicine course!

Could you please explain how humidity affects transpiration in plants? I mean, what are 'concentric shells'?

Also, did you feel the topics in A2 Biology were much harder than topics in AS Level? Or were they about a similar level in difficulty?

What exam board are you?

Don't know what concentric shells are, I'm AQA.

High humidity= smaller water potential diffusion gradient= transpiration slower

And opposites... in a very simple term!

Reply 282

username2396569

Original post by Bluebird38

Hey, now I'm no botanist, but I think Sammy's explanation is pretty good. Basically, if it's humid, then less water can evaporate (this is why you feel hotter in humid conditions eg steamroom). Think of it like this, evaporation is the change of phase of H2O from liquid to gas, it's an equilibrium, and if you increase the "concentration" of gaseous H2O (ie water vapour) then the equilibrium will shift so that less liquid water becomes water vapour. If less water can evaporate, then less can be pulled up by cohesion-tension ie transpiration. Less evaporation = less transpiration. Just remember that and you're sorted.

As for difficulty in topics, I'm going to be awkward and say that I actually found A2 easier than AS, but personally, this is because I was under a lot of stress and pressure in year 12 to get lots done to help me get into medical school (volunteering/sport/work placements etc) so I had less time to devote to my work. Also, once I got my AS grades I had the confidence and so A2 was much easier for me. But I'm weird in that way, the general concensus is that A2 is harder! haha

Reply 283

username2396569

Original post by Bluebird38

Oh and I also don't know what a concentric shell is, I even googled it and it doesn't seem to exist.. was it a typo?

Reply 284

username2396569

Original post by sammy2012

You're predicted an A*? What are you worried about? :wink:

haha. I do have my A2 biology notes only, but they're pictures of handwritten notes and I feel like they don't have much value. I can send them if you want, but I feel you'd be better off getting a textbook and making your own notes! My notes do have some explanations on trickier concepts, but they're a bit hard to read, so it's up to you

Reply 285

Bluebird38

Original post by AortaStudyMore

Thanks ever so much for your response, Aorta, you explained that very clearly :smile:

Spoiler

Reply 286

sbscx28

Hey man..

I was just wondering is it bad that I'm going through past papers and marking (Bio + Chem) half-heartedly most of the time... Although I do plan on definitely going through the marking all again intensely as the exams get closer?

Reply 287

username2396569

Original post by sbscx28

yh don't worry that's fine honestly, it's normal to not be that interested in doing and marking past papers, because at the end of the day they don't count, so I doubt anyone really puts all their efforts into anything other than the real exams.

Reply 288

Logic4Life

Original post by AortaStudyMore

Hi do you have any recommendations for the "suggest" questions that crop up in all the exams because the mark scheme usually has specific abstract answers that confuse me. Also how do you think I should revise for the practical questions that come up eg "Suggest how the students can increase the validity of their results" because they also confuse me. Thanks.

Reply 289

najmat

How to study for the BMAT exam? How to get get A* at bio , chem and maths A level ? Can I study As and A2 in one year and get A* in all subjects ? How to get a work experience ? Im self-studying for my A levels so can I get A* with the help of Youtube ? Thanks :smile:

Reply 290

username2396569

Original post by Logic4Life

So I think the reason why the mark scheme has such abstract answers is because when they mark it they take into consideration what people write, and if people have written valid answers then they incorporate them into the mark scheme. Also, it's worth noting that examiners probably aren't as strict as you think when marking these, as long as you get the general idea, they will give you the marks, so fear not. But yh, these questions do what they say on the tin really, they're asking you to suggest what you think will be the correct answer, you just need to write what makes sense to you, it's always worth sticking to logic, go with your heart, because what I always find is that if you overthink things, then you begin coming up with overcomplicated and incorrect answers. So write what comes to mind straight away (within reason of course, don't just write "bananas" if that's the first thing that comes to mind...) and then don't change that answer unless you have a brain wave. I seriously don't recommend sitting there for ages pondering all the different possible answers, because the more complicated the answer, the less likely it is to be correct.

As for practical questions, it might be worth just googling the difference between validity, reliability, reproducibility, accuracy etc etc, once you understand what they are, then it becomes easier to know how to improve them in an investigation. Usually though they're often used interchangeably, so you could probably get away with saying the classic "increase the sample size" or something in response to that question. But you should probably look up the technical definition, because the answer might be "increase precision of equipment" or "take more repeats" or whatever

Reply 291

username2396569

Original post by najmat

woah that's a lot of questions, so I'll try and keep the answers short, for the bmat, do past papers and read the online textbook that is released every year, and practise essays, a poor essay can ruin your whole bmat score despite the result in the other 2 sections. As for the second question, put the hours in and be interested in the subject and you can get an A*. Make sure you understand the content, don't just memorise it. I'm not sure about studying AS and A2 in one year because idk how A-levels work anymore with the single-exam structure thingy that's been introduced, you might have to ask someone who's a bit more knowledgable in that area, it's been over 2 years since I did my A2 levels now and things are slightly different now I think haha. For work experience, just apply to hospitals, the big teaching hospitals are the best for placements, and don't be afraid to apply for a hospital that's far away from where you live, you need to learn independence for uni anyway so you might as well start early! As for the final question, i don't see why you can't get A*s if you're motivated, although I wouldn't use youtube, buy yourself some exam board accredited textbooks and learn from those, you can easily get A*s from textbooks alone, although having a teacher does help (but I can deal with any queries you may have)

Good luck bud