i am pretty sure its B...because the code in trna will be the opp...n dna is the opp of trna....hope u get what i mean
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AS Biology P1 MCQs Preparation Thread
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14) to check whether a solution contains reducing sugar, you just need to add Benedict's Solution. but for non-reducing sugar you need to boil it with acid and then neutralize and then add Benedict's solution. the answer is B beacuse it gives negative result with reducing sugar and positive (that is, change in colour from blue to orange, yellow, green or red depending on the conc. of non-reducing sugar) with non-reducing sugar.
22) pulmonary artery is the blood vessel taking de-oxygenated blood from the heart to the lungs for the blood to get oxygenated. so, the partial pressure in the pulmonary artery has to be low as all the oxygen has been used around the body in respiration. but the partial pressure in never zero. so answer is B.
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can anybody telll me why we measure width of cell walll in nanometers?
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Hey people could you please help me with these:
QN PAPER: http://www.xtremepapers.com/papers/...nd AS Level/Biology (9700)/9700_w11_qp_12.pdf
MS: http://www.xtremepapers.com/papers/...nd AS Level/Biology (9700)/9700_w11_qp_12.pdf
qn 10 - why not A? I mean doesn't the green signify a little non-reducing sugar is present?
qn 21 - why A and not C?
qn 28 - might be a silly qn but am kinda messed up so a little help would be appreciated
qn 34 - why C and not D?
qn 39 -
thanx a lot and God bless you for your help!
QN PAPER: http://www.xtremepapers.com/papers/...nd AS Level/Biology (9700)/9700_w11_qp_12.pdf
MS: http://www.xtremepapers.com/papers/...nd AS Level/Biology (9700)/9700_w11_qp_12.pdf
qn 10 - why not A? I mean doesn't the green signify a little non-reducing sugar is present?
qn 21 - why A and not C?
qn 28 - might be a silly qn but am kinda messed up so a little help would be appreciated
qn 34 - why C and not D?
qn 39 -
thanx a lot and God bless you for your help!
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A little off-topic but does anyone know where to find the grade thresholds of papers before 2006? Back then they weren't printed as seperate documents so I don't know where to find them. I need those to evaluate myself. Thanks
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Can anyone show me how to work this one out?
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1.5 / 2 = 0.75 second (only 1 cardiac cycle)
60 / 0.75 = 80
(per minute)
Hope it helps.
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Why is 1.5 the time for 2 cardiac cycle?? Isnt a cardiac cycle from one AS to the next(or 1 VS to the next/from 1Diastole to the next)??
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(What is a mesosome and what is its function?? and Why is cellulose cellwall not a part of a phtosyntheric prokaryote?
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mesosomes r intense foldings or invaginations of d bacterial wallsassosiated with DNA during cell division and helps with formation of cell wall
http://http://www.xtremepapers.com/...and AS Level/Biology (9700)/9700_s06_ms_1.pdf
Q13
Q17
Q19
Q30- impossible to do!!!!!!!!!!!!!!
Q36
Q13
Q17
Q19
Q30- impossible to do!!!!!!!!!!!!!!
Q36
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Q13) B and D are obviously wrong. Product concentration will not decrease to zero. So, left A and C. product concentration will not come to the same level as X because enzyme will denature. So, the answer is A.
Q17) Water will diffuse into cell. Water potential near to zero. Pressure potential become more positive. Answer is A.
Q19) Answer is D. there'll be double the chromatids and chromosome because after interphase, everything doubled. spindle will not form yet (before prophase). it only forms after metaphase. (correct me if it's not after metaphase cuz it's somewhere along there..) Nuclear membrane will still present before prophase.
Q30) im confuse with question 30 too.. sorry.. >_<
Q36) answer is B. P must be the antigen. R is b-lymphocyte because it has to create clones, which is the "multiplication". and Q will be t-cells..
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30 is not quite impossible.
See, when the ventricles begin to contract the AV valves closes instantly. But initially the semi-lunar valves are also closed after the previous ventricular diastole and does not open until the pressure in the aorta rises sufficiently. So, both valves are closed. These two events are represented by 1 and 2 in the graph.
Again, during the next ventricular systole the semi-lunar valves snap shut as the pressure in the aorta drops. The AV valves are also closed initially as the atrium did not begin to contract yet. So, both valves are closed. time between point 3 and 4.
Add the times between the two sets of points and you get .07 which is C.
If you're still confused, check this video-
http://highered.mcgraw-hill.com/sit...22/animation__the_cardiac_cycle__quiz_2_.html
Hope this helps!
If u guys see the examiner report of that particular paper: http://www.xtremepapers.com/papers/...A and AS Level/Biology (9700)/9700_s06_er.pdf , you will see that question no.30 was withdrawn from the examination due to difficulties in reading the graph. The sum of the time between 1 and 2, and 3 and 4 does not give the exact answer 0.07s. This particular question was repeated in the last session: http://www.xtremepapers.com/papers/...nd AS Level/Biology (9700)/9700_w11_qp_11.pdf (Q. 24). Here the graph can be read easily and gives the exact answer (0.07s)30 is not quite impossible.
See, when the ventricles begin to contract the AV valves closes instantly. But initially the semi-lunar valves are also closed after the previous ventricular diastole and does not open until the pressure in the aorta rises sufficiently. So, both valves are closed. These two events are represented by 1 and 2 in the graph.
Again, during the next ventricular systole the semi-lunar valves snap shut as the pressure in the aorta drops. The AV valves are also closed initially as the atrium did not begin to contract yet. So, both valves are closed. time between point 3 and 4.
Add the times between the two sets of points and you get .07 which is C.
If you're still confused, check this video-
http://highered.mcgraw-hill.com/sit...22/animation__the_cardiac_cycle__quiz_2_.html
Hope this helps!
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If u guys see the examiner report of that particular paper: http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Biology (9700)/9700_s06_er.pdf , you will see that question no.30 was withdrawn from the examination due to difficulties in reading the graph. The sum of the time between 1 and 2, and 3 and 4 does not give the exact answer 0.07s. This particular question was repeated in the last session: http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Biology (9700)/9700_w11_qp_11.pdf (Q. 24). Here the graph can be read easily and gives the exact answer (0.07s)
I noticed that. when you read the graph the time is a little more than .07 but not by very much. It's difficult to read it accurately.
But you see, you don't know what's in the examiners report while you're still giving the paper, and if i had given that particular pper this is what i would have done.
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people am reposting my qns, can someone please helpHey people could you please help me with these:
QN PAPER: http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Biology (9700)/9700_w11_qp_12.pdf
MS: http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Biology (9700)/9700_w11_qp_12.pdf
qn 10 - why not A? I mean doesn't the green signify a little non-reducing sugar is present?
qn 21 - why A and not C?
qn 28 - might be a silly qn but am kinda messed up so a little help would be appreciated
qn 34 - why C and not D?
qn 39 -
thanx a lot and God bless you for your help!
Exactly! even if the answer is not exact, you should select the option closest to your calculated value. The concept behind the calculation is what really matters.I noticed that. when you read the graph the time is a little more than .07 but not by very much. It's difficult to read it accurately.
But you see, you don't know what's in the examiners report while you're still giving the paper, and if i had given that particular pper this is what i would have done.
It is quite useful in Physics Paper 1 and even in Bio now...qn 10 - It cannot be solution 2 since the colour before adding acid and neutralising was orange and the colour did not shift towards red after hydrolysis with acid, which would have been the case, had the solution contained non-reducing sugars. The green colour after hydrolysis is due to the reducing sugars. Remember, to confirm presence of non-reducing sugar, the colour should always become more positive for the test after hydrolysis.people am reposting my qns, can someone please help
qn 21 - The answer is infact C, check the MS: http://www.xtremepapers.com/papers/...nd AS Level/Biology (9700)/9700_w11_ms_12.pdf
qn 28 - Its vessel and the tissue is xylem since you cannot see any sieve pores and sieve plates (present in phloem) and the structure is continuous/hollow tube with spots, indicating pits in the walls (which are a feature of xylem vessels).
qn 34 - Only C is the effect of smoking. Tar is cigarette smoke stimulates goblet cells to secrete more mucus, so the goblet cells become enlarged. D cannot be linked to cigarette smoke.
qn 39 - 1st we have to calculated the net primary productivity which is = gross productivity - energy loss in respiration, where gross productivity is light energy - reflection and transmission (1000 000 - 990 000 = 10 000). Thus net productivity = gross - respiration = 10 000 - 5000 = 5000. The percentage is then = (5000/1000000) x 100 = 0.5 %