Help in Prac NEEDED! (1 Viewer)

[arson_system]

Hiya, has anyone done or knows how to do a prac on finding the effect of increased temperature and change in substrate concentration on one named enzyme? I have chosen rennin as my enzyme but i am having lotsa trouble trying to create a prac with it...so any help offered will be much appreciated!

 

[babydoll_]

dp:
* identify data sources, plan, choose equipment or resources and perform a first-hand investigation to test the effect of:
- increased temperature
- change in pH
- change in substrate concentrations on the activity of named enzyme(s)

Use hydrogen peroxide as the catalyst and potato (starch) as the substrate. Since you are not sure about rennin you should probably not use it. Most students here use starch and hydrogen peroxide, I think.

Set up testtubes of potato mixture at various temperatures and pHs. Add hydrogen peroxide, and record the time it takes to change colour (i think it goes to black).

Generally, as temperature and substrate concentration increases, rate of reaction increases. With pH, it increases towards a peak somewhere at 6 I think? then decreases.

Correct me if I'm wrong, people - it's been a while!

 

[Tommy_Lamp]

nancy I dont think they can ask you a question on a specific test, rather they ask "you tested on of the following" etc. At least thats what i've noticed in the 40 or so test papers ive done lol

Temperature is the easiest one, but ill post a prac for each.

To demonstrate the effect of increased temperature:

Make a rennin solution by dissolving a junket tablet in distilled water.
Add the same amount of rennin solution to a number of test tubes of milk.
Place test tubes in a number of different water baths at temperatures ranging from 0oC to 60oC. Make sure each water bath is kept at a constant temperature.
Time the interval between adding the rennin and curdling of the milk.

To demonstrate the effect of change in pH:
Make solutions of junket covering a range of pH.
Add the same amount of rennin solution to milk.
Place in a water bath kept at a constant temp 37oC.
Time the interval between adding the rennin and curdling of the milk.

To demonstrate the effect of change in substrate concentration:
Make different concentrations of the substrate by diluting the milk with distilled water or by using powdered milk to get different concentrations.
Add the same amount of rennin solution to the milk.
Place in a water bath kept at a constant temp 37oC.
Time the interval between adding the rennin and curdling of the milk.


Hope that helps.

 

[arson_system]

omg! babydoll & tommy lamp...u guys don't know how much ur help means ta me...it has helped me see da prac in a clearer way now if that makes sense...thanks so much n i'll tell u how it went when i'm done with it...THANKS SO MUCH!!!

 

[Tommy_Lamp]

Glad to help