A level Biology: Post your doubts here!

[thats_me]

lol... i tried to convert the mew in cm..

Oh, That would work too
Then it'll be 2/0.0007

 

[DeViL gURl B)]

http://papers.xtremepapers.com/CIE/...nd AS Level/Biology (9700)/9700_s13_qp_11.pdf

Question 5 is it cuz. Mitochondria supplies energy?

 

[DeViL gURl B)]

http://papers.xtremepapers.com/CIE/...nd AS Level/Biology (9700)/9700_s13_qp_11.pdf
Question 22? How???

 

[♣♠ Magnanimous ♣♠]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Biology (9700)/9700_s13_qp_11.pdf

Question 5 is it cuz. Mitochondria supplies energy?

yeah.. !! you are right it is because without mitochondria there will be no energy so no metabolism..... so overall mitochondria is needed.

 

[♣♠ Magnanimous ♣♠]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Biology (9700)/9700_s13_qp_11.pdf
Question 22? How???

listen there are max num of hyrogen bonds are 3 between Cand G so 700*3 = 2100 simple
see that maximum is highlighted that why i got the answer. just observe ques clearly..

 

[DeViL gURl B)]

http://papers.xtremepapers.com/CIE/...nd AS Level/Biology (9700)/9700_s13_qp_11.pdf

Guys for question 15 can't we say C?
Cuz substrate Y CAN NO LOGER BE FORMED!

 

[DeViL gURl B)]

listen there are max num of hyrogen bonds are 3 between Cand G so 700*3 = 2100 simple
see that maximum is highlighted that why i got the answer. just observe ques clearly..

Ohh okhay .. I was dividing by 2! Thank u!

 

[Sarah_3420]

guys please http://papers.xtremepapers.com/CIE/...and AS Level/Biology (9700)/9700_w06_qp_1.pdf
no.1 why is it B?

 

[thats_me]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Biology (9700)/9700_w11_qp_11.pdf

Q14?? sum1 plz explain

Animal cells don't have cell walls so there is free entry of water & excess is removed
Plant cell walls are completely permeable, but only until the cell is turgid
After that it would restrict water I.e to prevent it from bursting

 

[♣♠ Magnanimous ♣♠]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Biology (9700)/9700_s13_qp_11.pdf

Guys for question 15 can't we say C?
Cuz substrate Y CAN NO LOGER BE FORMED!

well when i read the textbook the diagram shows that the end product acts in enzyme 1which directly means that there would be increase in conc of X. simple.

 

[princeali97]

http://papers.xtremepapers.com/CIE/...and AS Level/Biology (9700)/9700_w06_qp_1.pdf
Q11.probably the most irritating question ._.

 

[♣♠ Magnanimous ♣♠]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Biology (9700)/9700_s13_qp_11.pdf

Guys for question 15 can't we say C?
Cuz substrate Y CAN NO LOGER BE FORMED!

i forgot to write enzyme 1 now check the answer please.

 

[zain ul abidin]

http://papers.xtremepapers.com/CIE/...nd AS Level/Biology (9700)/9700_w13_qp_13.pdf
Q21

 

[♣♠ Magnanimous ♣♠]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Biology (9700)/9700_w06_qp_1.pdf
Q11.probably the most irritating question ._.

you have to remember this two things... almost no explanation.... just see that water forms hydrogen bonds.

 

[DeViL gURl B)]

i forgot to write enzyme 1 now check the answer please.

Yeah the answer is inc. the X

 

[thats_me]

http://papers.xtremepapers.com/CIE/...nd AS Level/Biology (9700)/9700_w11_qp_11.pdf can I please get a detailed explanation for Q5?

 

[♣♠ Magnanimous ♣♠]

 

[thats_me]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Biology (9700)/9700_w13_qp_13.pdf
Q21

Base pairing occurs during translation ( between codons & anticodons)
Purines have a double ring structure where as pyrimidines have a single ring
Base pairs are of equal lengths
Uracil forms 2 hydrogen bonds with adenine
So statements 1& 3 are correct

 

[DeViL gURl B)]

View attachment 41574

It's D cuz myoglobin has in,y one polypeptide chain..where as a quaternary structure should have more then two polypeptide chains.

 

[daredevil]

http://papers.xtremepapers.com/CIE/...nd AS Level/Biology (9700)/9700_s13_qp_52.pdf

How do we perform the dilution on GA ?

also plz tell me the method of performing serial dilution.... i have totally forgotten x__x