BIOLOGY practicals help

[babycry]

Im doing my AS bio next year in may/june.. way bout youu?? ^^

 

[Emily793]

as bio this year!

 

[babycry]

well best of luck

wer you from?

 

[Emily793]

you too!!! im from mauritius and u?

 

[nano9595]

Emily im appearing for AS bio too this session
i hope that all the papers would be easy especially paper 3
anyways gud luck

 

[memyself15]

Emily im appearing for AS bio too this session
i hope that all the papers would be easy especially paper 3
anyways gud luck

good luck!!

 

[Emily793]

i really hope so after what ive heard about p4 im really scared cambridge seems to want all of us to fail!!

 

[babycry]

I'm from zambia
errm best of luck guys.. I'm writing next year ^^ muahahahahahahah

 

[nano9595]

i really hope so after what ive heard about p4 im really scared cambridge seems to want all of us to fail!!

yeah i ve also heard about Paper 4 from my friends i just hope our exam wouldnt be filled with
tricks and suggesting questions cause i really dont want to resit in june with babycry

 

[babycry]

you should rest with me as i will be the reason cambridge will moderate

 

[rz123]

Guys how do you do this question?
how do you count the divisions, the marking scheme does not make any sense to me. Please solve it..

It's question number 2 in both 31/32 oct/nov 2008 paper

http://www.xtremepapers.com/CIE/Interna ... _qp_31.pdf
http://www.xtremepapers.com/CIE/Interna ... _qp_32.pdf

Thanks in advance

So you count the number of eye piece graticule units in fig2.2. To me, it looks about 8 units. Then compared with the stage micrometer, 8 eye piece graticule units is same as 9 stage micrometer divisions.

We have been told that each division on the stage micrometer is 0.1 mm.

Therfore we divide; (9 x 0.0001) /8. We do this so as to divide the 8 eye piece graticules by 9 of the stage micrometer divisions. As a result we know the size of each eye piece graticule unit.......which is.....0.0001125 metres.

So....each eye piece graticule unit is 0.0001125 units therefore 8 of those would give us the width of the lumen (since 80 eye piece graticule units=the width of lumen) so you just multiple 8 by 0.0001125

The answer is 0.0009. I know the mark scheme is pretty confusing. The stuiped thing is it doesn't even give you any marks for getting the answer. You only get the four marks for collecting the data and writing it down.

Hope that helps you out

yes it helped. Well done kung fu panda! Thanks i always forget this method!

 

[Emily793]

hey guys any predictions for bio p33 tomorow???

 

[rahultaneja2010]

any predictions for 35 ?

 

[Emily793]

hey guys anyone got notes for bio practicals??? :wink:

 

[rz123]

yeah here there are...download these:-
http://studyguide.pk/?p=580 if this doesn't work find from this web studyguide.pk go to bio handouts nd then practical notes

 

[Emily793]

ive tried that too but it wont give anything jst a blank page.. can you email it to me instead?

 

[panda222]

ive tried that too but it wont give anything jst a blank page.. can you email it to me instead?

Hey emily....not sure if you'll get this in time but oh well.

I ran into the same trouble. The problem is that the page takes a long time to load and until it loads fully it'll show up as a blank page. So just click on that page and wait for ages. It'll come up eventually.

An alternative is that you can right click on the download button and click save as. Then once it finished downloading then just open the file and you'll be fine.

 

[anahita16]

food tests on
http://homepage.mac.com/hgsdietz/NEW_10 ... es/78.html
http://www.biotopics.co.uk/nutrition/benedt.html

 

[sweetiepie]

FOOD TESTS
Starch:
Iodine, observe a colour change from brown to blue-black.

Reducing Sugars:
Cut or grind off a small sample and add it to water to attempt to dissolve it. Then add Benedict's solution and heat using a waterbath. Observe a colour change from blue to brick-red.

Protein:
Cut or grind off a small sample and add it to water to attempt to dissolve it. Add potassium hydroxide and copper sulphate. Observe a colour change from blue to purple.

Fat:
Cut or grind off a small portion. Place in a test tube of ethanol and shake. Add the liquid part of this mixture to a test tube containing water. Observe a cloudy emulsifying change.

 

[Emily793]

here we are, done with practicals!!!! how did you find the paper guys??