AS-Bio - Vit C in fruit practical exam question HELP!!

try reading this part .....this is all practicals in short
https://www.google.lk/url?sa=t&rct=j&q=&esrc=s&source=web&cd=6&cad=rja&uact=8&ved=0ahUKEwjtrOOtuZjMAhWHm5QKHXkiBh0QFghEMAU&url=http%3A%2F%2Fwww.thestudentroom.co.uk%2Fattachment.php%3Fattachmentid%3D514015%26d%3D1458392118&usg=AFQjCNGTiEqNvtFLf7d-jSz9QFgcQk0m4Q&bvm=bv.119745492,d.dGo

Hey. I have something you could use.

Thank you!!!

Wow this must be good as you both linked me the same file!! Would I be prepared enough for the exams just with this summary of the core practicals? What way did you learn/memorise them?

Thank you!!!

Wow this must be good as you both linked me the same file!! Would I be prepared enough for the exams just with this summary of the core practicals? What way did you learn/memorise them?

Thank you!!!

Wow this must be good as you both linked me the same file!! Would I be prepared enough for the exams just with this summary of the core practicals? What way did you learn/memorise them?

how many units are you doing this MAY ?

You will absolutely not feel ready by just reading the summary. If you have any questions you may ask around. But really try and understand the practicals and do past papers because Edexcel is never straightforward. I memorized many experiments by doing past papers. They kind of repeat experiments but in different contexts. They may surprise you with something completely different. So you need to understand the question and modify the original experiment accordingly. If you don't understand what I am talking about then attempt 5) b) ii) on this paper and tell me how you found it. http://qualifications.pearson.com/content/dam/pdf/International%20Advanced%20Level/Biology/2013/Exam%20materials/WBI01_01_que_20150521.pdf

More Enzyme activity questions that I'm struggling with


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More Enzyme activity questions that I'm struggling with


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More Enzyme activity questions that I'm struggling with


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The answer for the second experimentLipase is an enzyme which breaks down triglycerides such as lipids.Use about 7 different concentrations of triglycerides but same volume.Add lipase with same concentration and volume to each triglyceride concentration.Measure the pH of solution using a pH indicator for a given timeRepeat with same concentration and get average and also repeat with the other different concentrations.Plot a graph of volume produced against time....And use this to plot a graph for initial rate of reaction for each concentration.Controlled variablesTemperatureVolume and Concentration of Enzyme Lipase.Volume of Triglycerides (NOT concentration)Independent variable = Concentration of triglycerides.Dependent variable = pH

First of all, let's break things down. To write an experiment, you must use CORMS.
C - control: always include a control in your experiment, eg for the light intensity leaf experiment have an empty test tube with just some indicator in it...
O - organism: what organisms will be involved and what similarities do they need to have eg. same sex, age, health, ect
R - repetition: how many repeats do you do to make it more practical?
M - measurement: what do you plan to measure? eg growth length temperature weight size ect.
S - standard: what do you need to keep the same? eg time, diet, oxygen, light intensities pH ect

Now since you are comparing two types of mussels (the organisms in this case), you have to control factors like Age and Gender because if your mussels have different ages and gender, the effect of enzyme maybe different and this leads to errors. So always control these type of variable okay?

You have to repeat your experiment in order for you to get many results so that you can obtain the mean rate of enzyme activity. Repeats ALWAYS increase reliability of the experiment.

The above experiment requires you to measure the RATE of enzyme activity. Rate is always respective to time. REMEMBER THAT. Hence the " Amount of oxygen produced PER UNIT TIME". Eg. Per minute.

You need to keep all the variables that may affect this experiment constant. Enzymes are affected by temperature so keep temperature constant by using a water bath or an incubator. Also, concentrations and volumes of catalase enzyme and the substrate may affect the results so you need to use the SAME amount. eg. if you use more substrates than enzymes, the rate of reaction will be slow because all the active sites of the enzymes are used up.


The control for this experiment would be doing this experiment WITHOUT THE ENZYME. Do NOT get confused between "Standard" and "Control".

A Control is a test where the person conducting the test only changes one variable at a time in order to isolate the results. eg. The control of this expt, shows you the effect of conducting the experiment without the enzyme.

If you have any more questions, feel free to ask.

@Puddles the Monkey wanna shut this down?