Is this gcse biology cousework??? (I could have emailed mine to you, but my laptop has recently broken down and i've lost all my cousework)
This question, (Why is yeast a good source of catalase?), would come under preliminary work. In my experiments there were two main sources of catalase: from a plant (e.g. celery) or from yeast. Yeast is a better source of calalase than celery for the following reason.
1) In celery catalase is not found in as high a concentration than in yeast. Therefore by using yeast,(which has a higher concentration of catalase), a smaller amount of the source will be need for each experiment.
2) To extract catalase from celery a stock of celery needs to be made. This is done by mashing up the celery and mixing this with water. This is very time consuming.
3) It is impossible to justify that the concentration of celery in each of the different celery stocks' that will need to be made up for the investigation are equal as different celery stick contain a different concentration of catalase.
By using yeast as the source of catalase, one can ensure that the concentration of catalase remains constant throughout the investigation. This is done by using the same mass of yeast in each exeriment, (as a certain mass of yeast contains the same mass of catalase).
These are the only reasons i can think about off the top of my head, but if i think of anymore i'll be sure to write them down. N e wayz is ure investigation about the effect of the concentration of the substrate on the activity of the enzyme (as this is the one i did). I would be happy to help u with scientific knowledge or analysis if u get stuck.
no actually its for my as courseowork, ive nearly finished but i just needed to answer this last question. im doing about the effect of changing the concentration of substate and its affect on rate of reaction, were using hydrogen peroxide and catalase.