*Biology Paper 5 tips*

[oldfashionedgirl]

Can someone PLEASE explain me question 3, part (b) (ii) and (iii)
I don't understand a thing from the mark scheme!

http://papers.xtremepapers.com/CIE/...and AS Level/Biology (9700)/9700_s09_qp_5.pdf

 

[Paparazzi478]

hey can anyone explain me how to find E expected value in chi squared test
i know we can find by finding the mean of the observed value what is the other method
cause in nov 11 p53 question two i am not gettin the correct answer! Help!

 

[sagystu]

i need some help with point regarding precations or low risk experiment, what do i write and when do i write it ? i always find a mark for it in mark scheme.

 

[comrade]

hey can anyone explain me how to find E expected value in chi squared test
i know we can find by finding the mean of the observed value what is the other method
cause in nov 11 p53 question two i am not gettin the correct answer! Help!

The whole test has been explained in the book. In the dihybrid cross, you should get the ratio 9:3:3:1. So it should be like this:

9 (from the ratio)/the number of offspring from the dihybrid cross chart x total number of offspring. Same goes for 3:3:1. I'm not how to explain it here. :/ I myself didn't do anything. Doing it now.

 

[Amaryllis]

guys do we have to memorize formulas ? like for standard deviation and error , or the formula is mentioned in the question ???

 

[comrade]

i need some help with point regarding precations or low risk experiment, what do i write and when do i write it ? i always find a mark for it in mark scheme.

You have to always write precautions. Just have a look at a couple of mark schemes. First you have to write about independent variable, followed by dependent variable, standardizing variables, safety and then reliability. You'll get an idea for each experiment if you go through mark schemes.

 

[Marks&Spencers]

guys do we have to memorize formulas ? like for standard deviation and error , or the formula is mentioned in the question ???

No worries, you don't have to memorise it I'm pretty sure, they said so in the revision guide.

 

[comrade]

guys do we have to memorize formulas ? like for standard deviation and error , or the formula is mentioned in the question ???

The formulas are always there as far as I know. I have never memorised them before. But you should know what the symbols mean. Also stuff like mean percentage values, probability, null hypothesis etc.

 

[Paparazzi478]

You have to always write precautions. Just have a look at a couple of mark schemes. First you have to write about independent variable, followed by dependent variable, standardizing variables, safety and then reliability. You'll get an idea for each experiment if you go through mark schemes.

okay i tried solving it that way but still didnt get the answers did you do it??

 

[knowitall10]

okay i tried solving it that way but still didnt get the answers did you do it??

What's your question, Sis?

 

[comrade]

okay i tried solving it that way but still didnt get the answers did you do it??

I'm sorry. I haven't done much. I'm just going through Paper 52 and their mark schemes. I mostly wasted my time. -_- I wish I could help you there.

 

[knowitall10]

I'm sorry. I haven't done much. I'm just going through Paper 52 and their mark schemes. I mostly wasted my time. -_- I wish I could help you there.

*hi5* so did I... -__-

 

[comrade]

What's your question, Sis?

Question number 2 of NOV 11 P53 and here is the mark scheme.

 

[knowitall10]

Question number 2 of NOV 11 P53 and here is the mark scheme.

What about it?

 

[comrade]

*hi5* so did I... -__-

*Hi 5* I'm now cursing myself for wasting so much of my time. I wish I had done some practice before. Opened the papers after a year. Don't know anything about t-test and some terms that I don't even remember. Critical values, degrees of freedom etc. :/

 

[comrade]

What about it?

She says that she isn't getting the correct answer. Hope she replies in time.

 

[Soldier313]

For qn 1 b i of this paper, the standard deviation I calculated was 2.36, but the ms says 2.23 :/
Can someone please help?

http://papers.xtremepapers.com/CIE/...and AS Level/Biology (9700)/9700_y07_sp_5.pdf

Irfan1995 knowitall10
and everyone else
Thank you

 

[knowitall10]

She says that she isn't getting the correct answer. Hope she replies in time.

ok..for the chi squared part?

 

[oldfashionedgirl]

http://papers.xtremepapers.com/CIE/...and AS Level/Biology (9700)/9700_s09_qp_5.pdf

Someone PLEASE explain me question 3, part (b) (ii) and (iii)
help will be much appreciated!

 

[knowitall10]

For qn 1 b i of this paper, the standard deviation I calculated was 2.36, but the ms says 2.23 :/
Can someone please help?

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Biology (9700)/9700_y07_sp_5.pdf

Irfan1995 knowitall10
and everyone else
Thank you

I haven't done this paper....i feel like a useless jerk now... =/