A level Biology: Post your doubts here!

[sitooon]

why probes and agarose gel are added in electrophoresis >?

 

[6Astarstudent]

why probes and agarose gel are added in electrophoresis >?

probe to determine position
agarose for seperation and median

 

[Snow Angel]

Plz can anybody provide a link for 2013M/J resources..........ty

r u referring to the as level exam papers for biology?

 

[ZaqZainab]

Plz can anybody provide a link for 2013M/J resources..........ty

http://olevel.sourceforge.net/papers/ here

 

[joanna omar]

ASlam3lykom This thread is so informative thanks A lot

I Need Model answers of A level past papers but It wont be the mark-schemes way of answering ,with points but it would be better phrases and sentences
As I actually have difficulty in phrasing the sentences and way of writing perfect required answers.

 

[Snow Angel]

ASlam3lykom This thread is so informative thanks A lot

I Need Model answers of A level past papers but It wont be the mark-schemes way of answering ,with points but it would be better phrases and sentences
As I actually have difficulty in phrasing the sentences and way of writing perfect required answers.

u can look at the standard booklet if there is one.

 

[daredevil]

Hey can any of you answer this question for me :
Q. Describe the role of Gibbrellins in stem elongation. (4)

like a kind of a model answer as you would write in your exam in case the question comes.
Thankss in advance ^__^

 

[sitooon]

Hey can any of you answer this question for me :
Q. Describe the role of Gibbrellins in stem elongation. (4)

like a kind of a model answer as you would write in your exam in case the question comes.
Thankss in advance ^__^

This are things which you need to BY HEART IT !!
the answer will be clearly in your textbook and in order! just mark the important points and thats the answer and
you can check the mark scheme for reference

 

[daredevil]

This are things which you need to BY HEART IT !!
the answer will be clearly in your textbook and in order! just mark the important points and thats the answer and
you can check the mark scheme for reference

ummm do you have the biology as and a level book by mary jones??
look up the topic in that book and explain what i can include in the answer because apart from 2 points worth 2 marks altogether i find the topic irrelevant with example and stuff... -_- help

 

[sitooon]

ummm do you have the biology as and a level book by mary jones??
look up the topic in that book and explain what i can include in the answer because apart from 2 points worth 2 marks altogether i find the topic irrelevant with example and stuff... -_- help

The points quoted from my textbook are :
* Giberellin is plant growth regulator
*Active Giberellin stimulates cell division
*and stimulates cell elongation
*so causes plant to grow tall
*Applying giberellin to plants which are short such as cabbages stimulates them to grow tall
*Dominant allele regulates the synthesis of an enzyme that catalyse the synthesis of an active form of giberellin

this is worth 6 marks

 

[daredevil]

The points quoted from my textbook are :
* Giberellin is plant growth regulator
*Active Giberellin stimulates cell division
*and stimulates cell elongation
*so causes plant to grow tall
*Applying giberellin to plants which are short such as cabbages stimulates them to grow tall
*Dominant allele regulates the synthesis of an enzyme that catalyse the synthesis of an active form of giberellin

this is worth 6 marks

um yeah if there is a general question about giberellin then sure that answer is pretty strong.
but don't you think that when they ask about the 'role of giberellin in stem elongation' , the point about applying giberellin' can still be considered worth a mark?? Isnt it kinda like an application of the thing and not as much a ROLE??
and also when we are already saying that it is a plant grrowth regulator, can we still consider the point highlighted because it does no more than repeating the point isn't it??
#confused -_-

 

[sitooon]

um yeah if there is a general question about giberellin then sure that answer is pretty strong.
but don't you think that when they ask about the 'role of giberellin in stem elongation' , the point about applying giberellin' can still be considered worth a mark?? Isnt it kinda like an application of the thing and not as much a ROLE??
and also when we are already saying that it is a plant grrowth regulator, can we still consider the point highlighted because it does no more than repeating the point isn't it??
#confused -_-

All what you said is correct , Most of the points are related and bring up the same concept!
however, thats not my answer , i just saw a 6 mark question for the same question you asked and those were the points written
i am confused too

 

[daredevil]

All what you said is correct , Most of the points are related and bring up the same concept!
however, thats not my answer , i just saw a 6 mark question for the same question you asked and those were the points written
i am confused too

oohh ohkkaayy... well if anyone else has a better answer PLEASE SHARE!! :`)

 

[6Astarstudent]

Hey can any of you answer this question for me :
Q. Describe the role of Gibbrellins in stem elongation. (4)

like a kind of a model answer as you would write in your exam in case the question comes.
Thankss in advance ^__^

Gibbberellins is key to enzyme induction, by modifying genes Gibberellins speed up the process of making amylase. This allows faster hydrolysis of amylose to glucose which is further respired for ATP. This ATP is used to increase the rate of cell division of stem cells thus stimulating the growth of stems.

 

[daredevil]

Gibbberellins is key to enzyme induction, by modifying genes Gibberellins speed up the process of making amylase. This allows faster hydrolysis of amylose to glucose which is further respired for ATP. This ATP is used to increase the rate of cell division of stem cells thus stimulating the growth of stems.

Hey that is a pretty good answer..

sitooon u might want to go through this one...

 

[Igcse stuff]

Plz can anybody provide a link for 2013M/J resources..........ty

olevel.sourceforge.net/

 

[daredevil]

Heyey guys... just wanted to know if leaf abscission is included in the syllabus or not... well is it??

 

[Sam Ivashkov]

Hi,I have a question. Do water molecules pass the cell membrane by diffusion or facilitated diffusion? And if the answer is diffusion, why don't the hydrophobic tails (non-polar regions) repel the water molecules?

 

[asma tareen]

Th

Hi,I have a question. Do water molecules pass the cell membrane by diffusion or facilitated diffusion? And if the answer is diffusion, why don't the hydrophobic tails (non-polar regions) repel the water molecules?

I dunno if I'm right but I think both of these processes dont involve water transport I guess water is transported through osmosis :/

 

[Sam Ivashkov]

Th
I dunno if I'm right but I think both of these processes dont involve water transport I guess water is transported through osmosis :/

right. and since osmosis is nothing but a special type of diffusion of water molecules only, i guess it will fall under the diffusion category.