AS Biology CourseworkWatch
And cud ne1 help with a suitable range?
PH would have a similar effect to the copper sulphate as the H+ ions in the acid would behave much like the Cu2+ ions in copper sulpate solution, by affecting the ionic bonding among R groups.
Copper being heavy is totally irrelevant.
Thanks for all the help
in all honesty its by far the best method and the exam board will be expecting it
most places have one colourimeter, ive used one at school. i think it is included in the list of apparatus found in a school. so dotn worry if ure school doesnt have one....
Egg Albumen is a globular protein held together in the usual manner by interaction between R groups.
Some of the bonds between R groups are Ionic, ie a positively charged R group is attracted to a negatively charged R group and the force of attraction holds the shape of the protein.
CuSo4 disociates into Ions in solution. These Ions are also attracted to the charged R groups. the positive Cu ions are attracted to negative R groups, the Sulphate ions to the positive R groups. They effectively neutralise the charge on the R groups so that the R groups no longer bind to each other. This allows the protein to uncoil into long strands.
Some of the bonds in the portein strand are polar, slightly charged at one end.
H groups are slightly positive, and become attracted to the slightly negative O end of OH groups. As the protein has uncoiled the H and OH groups are free to line up. The resulting hydrogen bonds cause the molecules to stick together. It is this more compact regular arrangement of molecules that blocks the light and turns the albumen white.
Hope that's of some help. Mine has to be in tommorrow.
it doesnt matter if your school doesnt have a colourimeter, if you read the paper it says use anything you would expect to find in a school or collage.
which brings me onto the conclusion.....what do we write in it? do we have to do the whole ..."if i repeated this study i would change this... " because we dont actully carry out the study so how can we draw up a results table and graph if we have no results. oh and if anyone knows what a colourimeter measures in then plz let me know. thank u.
so any help at all would be apprieiated
any help would be appreciated.
I've also referenced the UK Learning Forum. It doesn't sound too bad as a reference I think.
It's mostly deduction. Copper sulphate consists of Ions. R groups bind to each other using Ionic attraction, which adding Ions will neutralise. It's then logic that the molecule will uncoil and bind to other protein mollecules in much the same way cellulose does when the H and OH groups on the main chain of the protein line up.
There are no dedicated sources on this that I have found, so the next best thing is to use what you do know and put two and two together.
i have been told to use a colourimeter (spelling?), that box type thing that shines light through and lets you know how much light is going through. it should help with telling how denatured the egg and copper (2) suphate solution is.
the concentrations i am going to use are 0.0 (pure water), 0.02, 0.04, 0.06, 0.08 and 0.1m. they seem the simplest to be able to work out for me although im not sure if all of this matters because i dont think that the experiment actually has to be done.
In conclusion, I wish to summarise what I put in mine in the hope of helping other people. Please understand that I by no means claim to say this is correct. It may well be completely wrong, so if you use this theory and it is wrong, on your own head be it. Thats my terms and conditions.......lol.
Ok....use a colourimeter.....or simply use the stronger concentrations as an easy comparision to the others. The choice is yours.
My explanation for the denaturation is a direct quote from my coursework so if you use it....PLEASE DO NOT SIMPLY COPY AND PASTE!
'Copper ions in copper (II) sulphate are highly electropositive. Within proteins exist ionic bonds, which form between polarised R groups. Because of the positive charge of the Cu2+ ions the copper ion then forms an ionic bond with the polarised R group, which is stronger than the already existing bond. As a result, the existing bonds are broken and the protein changes shape. This change in shape is responsible for the denaturation.'
A lot of this is simply repatition.
Hope that is of ANY help to anyone.....if you still have major problems....please dont hesitate to email me
Good luck all.....
sounds like loads of people have done different things. i've gotta few questions that need answerin...
does diluting the copper sulphate alter the ph?
how much albumen and copper sulphate do you recommend using?
what concentrations of copper sulphate did you use?
what part of the experiment involves a change of ph if all you're doing is changing the concentration?
If you can help please email me at [email protected]