To investigate the effect of pH on the rate of enzyme activity Flashcards
Do safety measures for this exp?
wear goggles and gloves
What do you do first with the celery?
weigh on a mass balance
What do you blend the celery with after weighing?
water
After blending the celery and water what do you do?
using coffee filter paper, filter it with a funnel and beaker
Where do you put the celery filtrate after filtering?
a graduated cylinder
After placing the celery filtrate into a graduated cylinder what do you do?
add a few drops of washing up liquid
After washing up liquid, what do you add to the celery filtrate?
pH buffer 2
Once pH and washing up liquid has been added to the celery filtrate what do you do?
place graduated cylinder into a waterbath @25 degrees C with a thermometer
What temp should water bath be, why?
25 C degrees, optimum temperature for enzyme activity
What do you put into a second graduated cylinder that goes into water bath?
hydrogen peroxide
Once both graduated cylinders are at 25 C degrees what do you do?
add the hydrogen peroxide to the celery and start your timer
How long should timer be set for?
1 minute x 3 times
What do you record over the time period?
volume of foam
Repeat experiment but what do you differently?
use pH buffers 4, 9 then 12 (so that you finish experimenting with pH buffer 2, 4, 9, 12)
After you have recorded all pH buffers what do you finish with?
graph results showing volume of foam and/vs. pH
What are the 2 takeaways/results?
- most foam was produced @pH buffer 9 = optimum pH for catalase to work
- no foam produced @pH buffer 2, 4 or 12 as catalase enzyme was denatured, no longer functioning
What type enzyme do you use for this experiment? What plant did you use as a source of enzyme?
catalase + celery
What do you use to tell what temperature the water bath is?
thermometer
