October 16, 2009
Objektif:To identify how does the temperature affect the rate of enzyme activity.
contanst variable: same amount of starch and amylase and iodine as well
manipulated : the temperature of water bath(0, 20, 37, 50,65 degree celcius)
responding : the presence of starch
Discussion : when starch is present,iodine will change from yellowish to blue.
- iodine will remain yellow when starch is dehydrolysis.(ie when amylase is digest stach ady)
- iodine will change to blue when amylase is denatured
Hypothesis: 1. at o .c , the enzyme is present,but it can't digest starch,hence u will get all the way blue colour when starch and amylase are mixing together .
2. at 20.c, the mixing solution(amylase and starch)
will change to yellow gradually after some time(approximately 20th minutes)
3. at 37.c , the mixing solution will immediately change to yellow.(our experiment show the positive result after 2 minutes),this is because 37.c is the optimum temperature for amylase activity)
4. at 50.c,the mixing solution will become yellow,then blue after approximately 37 minutes,this showing amylase is denatured.
5. at 60.c,the enzyme amylase denatured immediately,you will get blue colour all the way.
apparatus: the grey one is starch,the brown one is amlylase and it was smell unpleasant.Iodine to detect the presence of the starch.
this is the ambience at the iniation of the experiment.
.preparing for 50 and 65.c water bath.
han sian: what r u laughing at?
blur,but they were all becoming serious ady
i found out that students of sis 1 is quite spontaneous is using the appartus. gals group just realise that we should use the clicker after saw boys do so.From left to right: jia wei,han sian,zhe kang
either 50 or 65
shu yan and susan
i took from car park de.i wanna rush to home le.
dropping amylase to starch.
jia wei: what should i measure?
jia wei wan to kao lui while doing experiment,hahaha.
me,have to test the presence of starch every interval one minute.
mixing the solution together after stabilise their temperature in water bath for 5 minutes.
group 50 and 37 .c
han sian: what r u doing r?
yih kang: watch and see(we are science student,we should be curious about this)
the result of 20.c
the one and only malay student in our class,she is quite pity coz we always speaking chinese.
it is hard to get shu yuan photo,u know?
jia wei: 大功告成
cute pic taken .u guys know where is it ady,right?
well,quite a long didn't update my blog ady.
in fact,i am quite indolent to do so too,hehe.prefer to go facebook now.
coz you can receive more responds there.
however,there are still something that i will not post on facebook.
actually,there is nothing special event happened recently.i have create a new quiz,"how well did you know about Shuh Hong?" at facebook,
you can go here for the test.