AS Biology P1 MCQs Preparation Thread

[JulyMei]

By internal membranes it does not refer to double membranes. Do not confuse inner membranes with internal membranes!
Only mitochondria and chloroplasts have internal membranes (cristae and thylakoids respectively). Nucleus has a double membrane but no internal membranes.

ok.. thanks.
but can i know what does "internal membrane" means? I mean, the definition.

 

[JulyMei]

how to find this????
thanks in advance.




I dont understand this. Why can't the answer be C?

 

[Pinklady]

http://www.xtremepapers.com/papers/...nd AS Level/Biology (9700)/9700_w10_qp_12.pdf
PLEASE EXPLAIN Q# 26, 33 and 35
please please please!

 

[JD REBORN]

http://www.xtremepapers.com/papers/...and AS Level/Biology (9700)/9700_s08_qp_1.pdf
Q35

 

[aom]

how to find this????
thanks in advance.

View attachment 12528


I dont understand this. Why can't the answer be B?
View attachment 12532

38 is A because they asked for an energy pyramid.... so u ignore coloumn 2 , because its not a mass pyramid .... so u multiply the first column by the third column and then work it out the biggest down and the lowest is up ....
for Q 16 i think its either D or C , i go with C, but i don't have a reason.... but i exclude B because its curved into the inside and A because its a stalk.. so it must be curved down like the leaf also so the confusion is between C and D ... but C is less curved so thats why i chose it .... hope i helped

 

[sophiaaa]

Yes , both exocytosis n endocytosis ( i.e bulk movement of materials ) are energy consuming processes which means they require ATP !! Not sure about endocytosis of proteins but Yes proteins do move out of cell by exocytosis ( through exocytotic vacuole ) !!

endocytosis doesnot require enrgy bt exocytosis does..

 

[sophiaaa]

hmm, ok so looking at the equation again...
wp = sp + pp, in the sieve element the water potential is more negative, which means the solute potential is even more negative according to the equation, so if the water potential is lowering cuz of the assimilates the solute potential is even lower and it gives the answer C as well...

http://www.xtremepapers.com/papers/...nd AS Level/Biology (9700)/9700_s10_qp_11.pdf.q.no.2..

 

[sophiaaa]

..http://www.xtremepapers.com/papers/...nd AS Level/Biology (9700)/9700_s10_qp_11.pdf..q.no.33 and 2.nyone can help........

 

[JulyMei]

38 is A because they asked for an energy pyramid.... so u ignore coloumn 2 , because its not a mass pyramid .... so u multiply the first column by the third column and then work it out the biggest down and the lowest is up ....
for Q 16 i think its either D or C , i go with C, but i don't have a reason.... but i exclude B because its curved into the inside and A because its a stalk.. so it must be curved down like the leaf also so the confusion is between C and D ... but C is less curved so thats why i chose it .... hope i helped

wopss.. im sorry.. for Q16, i mean, why can't it be C? the answer is A though..
and for Q38, the answer is B..

 

[Ineedhelp]

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Biology (9700)/9700_w04_qp_1.pdf
questions 20,29 and 32 pleasee and 30!

 

[JulyMei]

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Biology (9700)/9700_w04_qp_1.pdf
questions 20,29 and 32 pleasee

Q20) Cell 1 is in prophase. Before prophase, it's interphase. chromosomes are replicated. So, cell 1 will have 46 x 2 = 92. When anaphase, sister chromatids move to opposing poles. So, the number of chromosomes will be back to original number, which is 46. So, answer is D.

Q29) Xylem made up of dead tissues (lignin), while phloem is made up or living cells. So, when plant is heated, living cells will lost the function but not dead cells. Therefore, xylem will not be affected and phloem will. So, answer is B.

Q32) 4 boxes = 1000cm^3
1 boxes = 250cm^3
2 boxes = 500cm^3 (tidal volume)

15 boxes = 3750cm^3 (vital capacity)
So, answer is B.

Hope it helps.

 

[sahania]

I'm confuse with this... the answer is A.. Why not B?

View attachment 12477

Yes , it should be A.In Prophase , Chromosomes become visible, the nucleolus disappears, the mitotic spindle forms, and the nuclear envelope disappears. That's it ... no reduction nothing....

 

[raamish]

http://www.xtremepapers.com/papers/...nd AS Level/Biology (9700)/9700_w11_qp_11.pdf

how to do qs 6

 

[raamish]

answer is A

 

[thu]

18 Male bees are haploid. They develop from unfertilised eggs. Female bees are diploid.
Which statements are correct?
1 All male bees are genetically identical.
2 Male bee sperm cells are produced by mitosis.
3 New combinations of genes only occur in female bees.


A 1 and 2 only B 1 and 3 only C 2 and 3 only D 1, 2 and 3

guyss em reposting this qst ..plz do help :|

I dont get why the ans is C. I think it's D cos all male bees should be genetically identical .

 

[raamish]

I dont get why the ans is C. I think it's D cos all male bees should be genetically identical .

yeh im having probs in this qs as well

 

[thu]

This is from paper w10_11, Q22.

The table shows the percentages of nitrogenous bases in four samples of nucleic acids.

Which base is adenine?

percentage of nitrogenous bases
sample:
A B C D uracil
1 19 31 30 19 nil
2 27 23 24 26 nil
3 25 25 nil 25 25
4 17 32 33 18 nil

Guys please help! I have no idea what this question is saying . What is 'nil' ?

 

[knightrider1994]

This is from paper w10_11, Q22.

The table shows the percentages of nitrogenous bases in four samples of nucleic acids.

Which base is adenine?

percentage of nitrogenous bases
sample:
A B C D uracil
1 19 31 30 19 nil
2 27 23 24 26 nil
3 25 25 nil 25 25
4 17 32 33 18 nil

Guys please help! I have no idea what this question is saying . What is 'nil' ?

Nil is 'zero' means no uracil is present. The answer is B. Its like as uracil is 25 in sample 3, adenine will be 25 as well as both are complementary. Moreover thymine will be nil where uracil is present so column C represents thymine. I hope it clears the doubts you have.

 

[knightrider1994]

I dont get why the ans is C. I think it's D cos all male bees should be genetically identical .

It has to be D ! Because 1 and 2 are inter-related. Mitosis produces genetically identical cells therefore both 1 and 2 are correct.

 

[sahania]