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AS Biology P1 MCQs Preparation Thread

Soldier313

Soldier313

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eyamwir said:
can we do it already? i dont mind either way, we will waste 2 weeks if we don't start
Click to expand...
Yeah i think we really need to start now so let's begin with mj/02 as our first paper inshaAllah:) hope every1s fine with that:)
 
thunderingthunder

thunderingthunder

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The sequence of bases on a messenger RNA molecule is shown.
A U C G A A G U U C G U
It was transcribed from one strand of DNA.
What is the sequence of bases on the complementary,non-transcribed strand?
A.A C G A A C T T C G A T
B.A T C G A A G T T C G T
C.T A G C T T C A A G C A
D.U G C U U G A A G C U A
Y is the answer B??
Shouldn't it be C?
 
S

Soulgamer

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thunderingthunder said:
The sequence of bases on a messenger RNA molecule is shown.
A U C G A A G U U C G U
It was transcribed from one strand of DNA.
What is the sequence of bases on the complementary,non-transcribed strand?
A.A C G A A C T T C G A T
B.A T C G A A G T T C G T
C.T A G C T T C A A G C A
D.U G C U U G A A G C U A
Y is the answer B??
Shouldn't it be C?
Click to expand...

Post the link to the question and marking scheme.
 
XPFMember

XPFMember

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Soldier313 said:
Feel free to discuss your bio p1 doubts here......and we go through each paper from 2002 towards 2011 and discuss the "hard" MCQs of each paper (or all if time isn't an issue)? This would be much better and organized rather than, say, having 5 different people posting different MCQs every minute making it hard to answer every one (idea by leosco1995 in the physics mcq thread:))
Further suggestions are welcome:)
Click to expand...
Aoa wr wb! I personally would prefer solving 2011 backwards..starting with nov 2011 :D
dunno what are all people up to..

P.S. Here's how you can manage your time preparing for Physics and/or Biology Paper:1 !
 
S

Soulgamer

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Lets set a goal. Every night, everyone should post how many papers they have solved just for fun. :p
 
R

rogue94

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thunderingthunder said:
The sequence of bases on a messenger RNA molecule is shown.
A U C G A A G U U C G U
It was transcribed from one strand of DNA.
What is the sequence of bases on the complementary,non-transcribed strand?
A.A C G A A C T T C G A T
B.A T C G A A G T T C G T
C.T A G C T T C A A G C A
D.U G C U U G A A G C U A
Y is the answer B??
Shouldn't it be C?
Click to expand...
The answer in B!!! C would have been the answer had the question asked about the transcribed strand. Since, you have to figure out the sequence of bases on the non-transcribed strand, simply replace all the U's in the mRNA sequence given with T's and you'll get your answer which is B. This shortcut can also be used when they give you DNA sequence or tRNA codons and ask you to find the sequence of bases on tRNA codons or DNA. You simply replace the the Uracils with the Thymines or vice-versa. This is because you first have to find out the complementary sequence on mRNA and then again find the complementary sequence for the mRNA sequence which you just found, which brings you back to the original sequence that was given in the question.

For this particular question 1st find the complementary sequence of bases on the DNA, which is the transcribed strand (given in option C) then again find the complementary sequence of bases on the opposite DNA strand (the non-transcribed strand, which has been asked for in the question). This brings you back to the original mRNA sequence (given in the question), with only the U's replaced with T's because its DNA and not RNA.
 
thunderingthunder

thunderingthunder

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rogue94 said:
The answer in B!!! C would have been the answer had the question asked about the transcribed strand. Since, you have to figure out the sequence of bases on the non-transcribed strand, simply replace all the U's in the mRNA sequence given with T's and you'll get your answer which is B. This shortcut can also be used when they give you DNA sequence or tRNA codons and ask you to find the sequence of bases on tRNA codons or DNA. You simply replace the the Uracils with the Thymines or vice-versa. This is because you first have to find out the complementary sequence on mRNA and then again find the complementary sequence for the mRNA sequence which you just found, which brings you back to the original sequence that was given in the question.

For this particular question 1st find the complementary sequence of bases on the DNA, which is the transcribed strand (given in option C) then again find the complementary sequence of bases on the opposite DNA strand (the non-transcribed strand, which has been asked for in the question). This brings you back to the original mRNA sequence (given in the question), with only the U's replaced with T's because its DNA and not RNA.
Click to expand...
Thank you..i got it:)
 
confused123

confused123

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the reaction rate of salivary amylasr with starch decreases as the concentration of chloride ions reduced. which of the following describes the role of the chloride ions.
a) allosteric inhibitors
b) co factors
c) coenzymes
d) competitive inhibitors

the ans is co factors. i never read about it in the book.
 
Saad (سعد)

Saad (سعد)

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I'm gonna spend the next two days, insha' Allah, reading the book from beginning to end.

=_= There's no point in solving MCQs if you forgot the theory, and preparing for Chem made me totally forget Bio theory.
 
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