Anyone studying A2-level Edexcel Biology A Salters Nuffield??

what are the different things we need to know calculations for, e.g. Q10, t-test, percentage change.etc??

t- test is used to see if there if there is a significant difference between two means of data. I.e if the difference in heart rate before and after exercise is significant. they will defo give the calculations. You basically just then find the degrees of freedom then see the critical value at p=o.o5.

q10 is just how much the rate of a reaction increases when the temperature increases by 10 degrees. you just divide the rate at say 40 degrees by the rate at 30 degrees.

percentage change is really simple just new- original/ original x 100

is this of any help?

Reply 1221

Diastal

6

Original post by bobby147

My notes say ethanoic acid,but i checked and ethanoic alcohol is mentioned.I assume both answers will get the marks ?

Yeah, I'm sure both will get the mark. Hopefully. Thanks for the links on the practicals btw they were really helpful!

Oh and when you do experiments with different temperatures, e.g: the brine shrimp experiment, you shouldn't really have a temp above 40. I saw this on a markscheme and it said that temperatures should not be above 40. So for the 5 different temperatures what I pick is 10,15,20, 25, and 30. First time I saw this in a markscheme I was surprised, but I guess it does make sense since temps above 40 may kill off the eggs, which wouldn't be much help when doing the experiment. This goes for most other experiments as well which contain living organisms, except ones such as the beetroot one.

Also, most people misspell colorimeter and write calorimeter instead. So be careful as these are two different pieces of equipment and you may lose out on a mark if you write calorimeter instead of colorimeter.

(edited 6 years ago)

Reply 1222

Unionjem123

10

What did people write for the devise question in paper 2 about earthworms and habituation?

Reply 1223

JTD99

9

Original post by wolfbook

Anyone know how paper 3 will be structured I have no idea what to expect :s-smilie:

everything from topics 1-8 plus there should be a 30 mark question, (multiple parts) on the scientific article

Reply 1224

Adam_chhetri

Whats the percentage/marks you need to average across the 3 papers for a B

Reply 1225

AD490995

13

Original post by Adam_chhetri

Whats the percentage/marks you need to average across the 3 papers for a B

I reckon about 60% going off the old spec requirements for a B and considering that the new spec is much harder.

Reply 1226

Adam_chhetri

Cheers

Original post by AD490995

I reckon about 60% going off the old spec requirements for a B and considering that the new spec is much harder.

Reply 1227

AnimeFreak101

12

Does anyone have a PDF document of the scientific article?

Reply 1228

bobby147

20

Original post by AnimeFreak101

Does anyone have a PDF document of the scientific article?

http://www.the-scientist.com/?articles.view/articleNo/41990/title/The-Energy-of-Life/
The science article it is based off,and it matches it word for word.

(edited 6 years ago)

Reply 1229

AnimeFreak101

12

Original post by bobby147

http://www.the-scientist.com/?articles.view/articleNo/41990/title/The-Energy-of-Life/
The science article it is based off,and it matches it word for word.

All of it? Thank you!

Reply 1230

bobby147

20

Original post by AnimeFreak101

All of it? Thank you!

Yes,I have compared it to the one we are given in school,and it matches word for word.

Reply 1231

AnimeFreak101

12

Original post by bobby147

Yes,I have compared it to the one we are given in school,and it matches word for word.

Well thank you once again! :smile:

Reply 1232

Diastal

6

Original post by AD490995

I reckon about 60% going off the old spec requirements for a B and considering that the new spec is much harder.

What? Are you being serious? The grade boundaries for biology are extremely low. No way is is gonna be 60% for a B. It was 54% for an A last year and its gonna be somewhere around 55-60% for an A this year too.

Reply 1233

COCO16382

2

Original post by Diastal

What? Are you being serious? The grade boundaries for biology are extremely low. No way is is gonna be 60% for a B. It was 54% for an A last year and its gonna be somewhere around 55-60% for an A this year too.

We hope... edexcel are so unpredictable!

Reply 1234

Philip-flop

OP

18

Can someone tell me what blood plasma is?

Reply 1235

Diastal

6

Original post by Philip-flop

Can someone tell me what blood plasma is?

You don't really need to know but its just basically some sort of liquid which is in our blood and it basically contains the blood cells. Thats all I know anyway.

- Contains red and white blood cells and platelets

Reply 1236

Philip-flop

OP

18

Original post by Diastal

You don't really need to know but its just basically some sort of liquid which is in our blood and it basically contains the blood cells. Thats all I know anyway.

- Contains red and white blood cells and platelets

Thank you

Reply 1237

AD490995

13

Original post by Diastal

What? Are you being serious? The grade boundaries for biology are extremely low. No way is is gonna be 60% for a B. It was 54% for an A last year and its gonna be somewhere around 55-60% for an A this year too.

This is going off previous years. Also it's important to remember that that a lot of the people who performed poorly last year, I.e the ones that came out with E and U grades will have most likely dropped out this year and thus won't be here this year to bring back down the grade boundaries. I know it's harsh but that's the reality. I'm not saying this years papers were easy, but I doubt that the grade boundaries will be 60% for an A, maybe 65-70.