Edexcel BIOLOGY Doubts!!!!

[Amii]

this is all u need to noe for the AS i think.... if u have seen any q like this in any pastpaper then do let me noe caz the controling of the heart beat by nervous system is in A2

The question is from Jan 2008 Unit 2B paper. It's the old syllabus - we don't have to know that for AS 

[guMnam]

if a risk assesment q is for 4 marks.. do we have to rite 4 risks.. or 2 risks and their controls/precautions

[noor.h92]

Hi,

has anyone done the 2011 biology paper 3. (As-level). In question 1ai- where you have to draw a graph what would be my x-axis and y-axis?


thanks in advance

[guMnam]

here are some unit 1 revision notes... good to go thru them

[Blizz_rb93]

january 2011 unit 1 question 1 b) where they give us this graph , how do we describe the results, ok i see the graphing for the control group and the treatment group but then theres that line in the middle of each bar i really dont get it :S
please help asap
thank you <3

[guMnam]

january 2011 unit 1 question 1 b) where they give us this graph , how do we describe the results, ok i see the graphing for the control group and the treatment group but then theres that line in the middle of each bar i really dont get it :S
please help asap
thank you <3

the line u r talking about is the error bar... it is a range in which the results cud have been... wat u can write abt it in the ans is tht.. the range was larger for the treatment group compared to the control group

mention tht the control group has shown an mean increase and treatment group has shown a decrease.. the diference is means is 70mm³ ull get full marks

[Blizz_rb93]

the line u r talking about is the error bar... it is a range in which the results cud have been... wat u can write abt it in the ans is tht.. the range was larger for the treatment group compared to the control group

mention tht the control group has shown an mean increase and treatment group has shown a decrease.. the diference is means is 70mm³ ull get full marks

Thank you!! i appreciate it, i understand it now

[8T]

Could someone explain in detail what is the effect of temperature( Low & High) on the permeability of a memberane ?

[guMnam]

how do we calculate the heart rate ?? frm a graph of  blood presure(kpa) /time (s) showing aortic and ventricular presure (left) ?

[~ Miss Relina ~]

here are some unit 1 revision notes... good to go thru them

to which book are the related to as they say see book page etc.

[~ Miss Relina ~]

Vincristine is a drug used in the treatment of cancer. It prevents spindle formation during mitosis. The result of a root tip squash on the roots grown in a solution of vincristine showed an increase in the percentage of cells found in one of the phases compared with roots grown in water. State the precautions that must be taken for the results of the comparison to be reliable

[MKh]

hey could someone plz tell me the procedure of this core practical --- how to investigate the effect of temperature on seedling growth rate? thnxx..

[guMnam]

Vincristine is a drug used in the treatment of cancer. It prevents spindle formation during mitosis. The result of a root tip squash on the roots grown in a solution of vincristine showed an increase in the percentage of cells found in one of the phases compared with roots grown in water. State the precautions that must be taken for the results of the comparison to be reliable

how many marks is the q for ??

the concentration of the solution shud be known and controlled..
the roots shud be of the same variety of plant..
the mass of root taken shud be same..

3 points for 3 marks

[guMnam]

hey could someone plz tell me the procedure of this core practical --- how to investigate the effect of temperature on seedling growth rate? thnxx..

umm y dont i remember any such practical :S

seen in any past paper ??

[Blizz_rb93]

For people interested in a list of all the practicals, here I attached a file that has all the practicals needed for you to know + questions related to that practical.

Enjoy