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can some one help me in questiom why it is B not A
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AS Biology P1 MCQs Preparation Thread
- Thread starter Soldier313
- Start date
The first question is very simple. An oxygen molecule has to diffuse to 5 cell surface membranes. Let me show you how, Check the uploaded file.
Reduction division means when chromosome number is halved. In first diagram you can see at point S, from diploid number there is a change to haploid number(halved) so we got S. The second is V has again from a diploid cell, gametes are formed which are haploid(half number of chromosome)
Hope that helped!
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can some one help me in questiom why it is B not A
Question number?
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The first question is very simple. An oxygen molecule has to diffuse to 5 cell surface membranes. Let me show you how, Check the uploaded file.
Reduction division means when chromosome number is halved. In first diagram you can see at point S, from diploid number there is a change to haploid number(halved) so we got S. The second is V has again from a diploid cell, gametes are formed which are haploid(half number of chromosome)
Hope that helped!
Thanksss!!!! I've confused about the layers things for so long. THANKS!!
Thanksss!!!! I've confused about the layers things for so long. THANKS!!
Do remember for Carbon dioxide it can be either 5 or 4 as Carbon dioxide also travels in the bloodstream rather than rbc's
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It can be 4 as carbon-dioxide will be directly transported by the blood in the form of hydrogen-carbonate ions. Hence no need to diffuse out of RBC's.
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it is Q 28 sorry i forgot to write it im only worried about the exam
it is Q 28 sorry i forgot to write it im only worried about the exam
A really simple one and needs no calculation. Wherever the graph is the steepest is the greatest change. In this case it is B.
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oh! right!! ok.. got it!! Thanks!!
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how to do this calculation?
why can't high temperature break ionic bond?
high temperature and pH change can break, right?
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yeah ryt. ohk
see the 5 membranes in the attachment....
2 of the alveolar wall
2 of the capillary wall
and 1 of the rbc
for the second.....reduction division is meiosis....they produce cells with half the number of chromosomes, like gametes. so where ever gametes or egg cells are produced reduction division occurs...
Attachments
http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Biology (9700)/9700_s11_qp_11.pdf
Q22 the answer according to the mark scheme is A....
why not D, i agree with the 1 and 2 but 3...sugar and phosphate bonds, do form...when the free mRNA nucleotides in the nucleus come and attach to the exposed template (a DNA strand) something forms the sugar phosphate backbone...so the sugar phosphate bonds are forming between the mRNA nucleotides...
4 even this seems true.....the free mRNA nuclotides in the nucleus come and pair with the exposed DNA strand according to compleentary base pairing rules....
so why A?
Q22 the answer according to the mark scheme is A....
why not D, i agree with the 1 and 2 but 3...sugar and phosphate bonds, do form...when the free mRNA nucleotides in the nucleus come and attach to the exposed template (a DNA strand) something forms the sugar phosphate backbone...so the sugar phosphate bonds are forming between the mRNA nucleotides...
4 even this seems true.....the free mRNA nuclotides in the nucleus come and pair with the exposed DNA strand according to compleentary base pairing rules....
so why A?
Because clearly the 4th process does not occur TWICE during transcription. I'm not sure about the 3rd one.
oh oh i ddnt even read the twice part
now i get it....even the sugar phosphate bonds form only once, between mRNA nucleotides...thnx!1. The only thing that matters the most is the 'tidal volume'. A and B have the greatest, i.e 0.6.
Now B has more breaths per minute than A. So clearly B would have absorbed most oxygen during those four minutes.
2. High temperature would break the Hydrogen bonds first. pH change would exclusively affect the ionic bond.
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Okay for the first Q. multiply each breath rate by the tidal volume this should give you the total Oxygen INHALED NOT ABSORBED in 1 minuite by whoever ok, then you find the diffrence betwwen the value you obtained anf the total lung volume the person with the largest diffrence is the person who absorbed the most oxygen e.g for B 15 x 0.6 = 9 right 9 - 6 = 3, 3 was the largest diffrence when i did the question so the anwser is B.
Q2 high temperature increase's the K.E puting strain on the bonds not breaking them eventualy the bonds will only break from weakest to strongest, PH will directly effect the ionic bonding. hope that was enough
http://www.xtremepapers.com/papers/...nd AS Level/Biology (9700)/9700_w11_qp_11.pdf
Can anyone explain why Q24 is C? I got B instead
Can anyone explain why Q24 is C? I got B instead
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The answer is A in the mark scheme, but why is it not C?? Heart is one of the chapters giving me a tough time.