BIOLOGY practicals help

[lychee26]

this is usually what should be done! i couldnt view the ms :sorry:

whats this!?

 

[Emily793]

this is the reply to eyamwir question above... the on he posted the question paper

 

[eyamwir]

this is the reply to eyamwir question above... the on he posted the question paper

thank you emily. i'll be doing my practical today, in the morning :s wish me tons of luck. so i just got to remember

for table
i)list all the experiments/labelled test tubes
ii)independent variable
iii)dependent variable
iv) rate if any experiment involve in measuring time
v) units in each heading
vi) do any repeats for the experiment if necessary, usually 3 trials.

for microscopy
i)magnification
ii)follow the instruction
iii)choose the easiest part to label ; cell wall, cell membrane, nucleus, cytoplasm
iv) eyepiece graticule and the stage micrometer
v) comparing the two different specimens shown : choose around 3-4 statement

i think that's it maybe

oh and errors! reducing errors and ways to improve experiments. isn't it all?

 

[Emily793]

Yes you are! And dnt forget imprvments! Good luck pal. Everyting gonna be ok. Ill pray 4 you! :good:

 

[eyamwir]

Yes you are! And dnt forget imprvments! Good luck pal. Everyting gonna be ok. Ill pray 4 you! :good:

thank you emily you're right i did my practical jn p36 it was okay. so i have a week left before paper 4 do you think i could study with you as well? is it possible

 

[Emily793]

yes why not eyamwir!!

 

[eyamwir]

wow thank you emily :') hmm can i have your email? i could communicate w you easily thro email i think i've seen your email in my hotmail is it the gmail?

 

[Emily793]

ive sent you my email add through pm. hope you get it. better use hotmail coz my gmail is not working properly.

 

[eyamwir]

ive sent you my email add through pm. hope you get it. better use hotmail coz my gmail is not working properly.

okay then. will add you up in a min

 

[eyamwir]

emily im online right now let's chat hehe cant reply your inbox something wrong with the connection

 

[panda222]

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

 

[Emily793]

what is the difference between low power diagram and high power diagram?

Low power is in other words a plan digram.. howere high power inolves details such as individual cells or organelles.

 

[panda222]

Emily could you check if i did the question above correctly. I'm not quite sure about it myself. The mark scheme doesn't tell you the answer, just the method.

 

[mrpaudel]

Can anyone draw a low power plan diagram labelling mesophyll cells and vascular bundle?

 

[Emily793]

you are right thats correct pal! :good:

 

[panda222]

you are right thats correct pal! :good:

When r u sitting ur prac?

 

[babycry]

Do you join points with a ruler or a curve when drawing a curve? loll :%)

And what is the test for starch when in a LOW CONCENTRATION as high concentration turns iodine in potassium iodide dark blue/black

tankyewww

 

[sweetiepie]

Biology Serial Dilation

viewtopic.php?f=7&t=5229




hope this helps

 

[Emily793]

you can do both either join with a line or curve.. personally i would go for line.. unless its a curve like the rate of enzyme action then its obvious that you have to use curve

 

[Emily793]

are you guys doing practicals on 8th nov too??
how was p4 guys?? i dont do it as i do bio as an AS... but my friends found it quite tricky and difficult..