A level Biology: Post your doubts here!

[Alazne Diamond]

Chloroplasts and mitochondria

Reason??

 

[benjamin123]

free a* quality revision notes at d2rek.wordpress.com

 

[6Astarstudent]

For paper5 .. all science subjects ..
do we have to write the answer for the 15 mark(phy) . 10mark(bio) ,7mark(chem) questions
in points or in story type??

bio essay based
chem, phy point based

 

[6Astarstudent]

Reason??

i doubt they'd ask such a bizarre question, but if you must, selecting mitochondria will be better. We don't even go into great detail on the double bi-lipid layer of the nuclear membrane anyway in A level.

 

[ahmed abdulla]

bio essay based
chem, phy point based

Is it for all papers ?

 

[Alazne Diamond]

i doubt they'd ask such a bizarre question, but if you must, selecting mitochondria will be better. We don't even go into great detail on the double bi-lipid layer of the nuclear membrane anyway in A level.

they did ask in M/J 2003 P1 Q. no. 2.....................anywayz thnxx

 

[ZaqZainab]

they did ask in M/J 2003 P1 Q. no. 2.....................anywayz thnxx

He was talking about explaining the reason they wouldn't ask you

 

[SilverCrest]

can someone explain why the answer to question 11 is A.Thanks!! =) =)

 

[Malik777]

View attachment 36636

can someone explain why the answer to question 11 is A.Thanks!! =) =)

As the frozen water has lower density it remained above the water, forming a layer during winter but as summer comes the frozen water melts and its density decreases. The nutrients dissolved in water as water is good solvent comes on the surface.

 

[Alazne Diamond]

He was talking about explaining the reason they wouldn't ask you

ik................itz a MCQ so ofcoz they won't ask da reason

 

[ZaqZainab]

ik................itz a MCQ so ofcoz they won't ask da reason

when you said "they did ask" quoting the post where he says "i doubt they'd ask such a bizarre question"
The bizarre question is stating the reason... and you said they have asked but they haven't asked you i was just clearing the fact you misunderstood

 

[Alazne Diamond]

when you said "they did ask" quoting the post where he says "i doubt they'd ask such a bizarre question"
The bizarre question is stating the reason... and you said they have asked but they haven't asked you i was just clearing the fact you misunderstood

lol k bt i guess he was tokin abt da question..........n abt dis msq if i jst need da answer den i can look at da mark scheme............so i was jst trynna knw da reason

 

[not.maria]

in the question:-
"State three features of the leaf, visible in Fig. 3.1, which show that it has developed in
a sunny position."
the markscjeme mentions
>smaller air spaces
>thick leaf

I dont understand how smaller air spaces are an adaptive feature.
Nor do I undertsnad how we are supposed to know if the leaf is thick or thin because for me 450micrometres in THIN.

Can anyone please explain?

THANKS!

 

[madoka]

could u plz help me

 

[madoka]

i want a help plz

 

[joanna omar]

i shall check and let u kno.

please can you explain the 5d) in paper 2 may june 2006 /9700 after looking at the answer the marking scheme gives for it?

qp link: papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Biology (9700)/9700_s06_qp_2.pdf

ms link: papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Biology (9700)/9700_s06_ms_2.pdf

THANKS

 

[joanna omar]

Re: Biology Doubt: Nervous System!

Assalamoalaikum!

Can someone please explain, what's refractory period? I am confused about it! =/

I need june 2013 and nov 2013 qp and ms please

 

[joanna omar]

AND PLEASE Anyyonee I need any guiddes or points that will help me proceed with paper 5 as itss so HARD !

 

[ZaqZainab]

lol k bt i guess he was tokin abt da question..........n abt dis msq if i jst need da answer den i can look at da mark scheme............so i was jst trynna knw da reason

well the reason is obvious that Chloroplast and mitochondria have internal membranes but it seemed like you need a reason why do they have internal membranes

 

[Khadija_1234]

Explain, interms of protein structure, how it is possible for each T cell receptor to bind specifically to one type of antigen. [3]
Please help. Thanks