Today in lab we started an enzyme experiment. We had a false start with some crazy quick setting jello, so we started over. We didn’t get to see the results during lab because the final jello didn’t set quickly enough (even though we used the quick set method!). It seems to have worked fine in the end, it just needed a little more time in the fridge. I posted the pictures/results below. We also finished our discussion of macromolecules and made DNA models! We talked about the basic structure of DNA and the components. Making the models really forces you to be clear about which part goes where and how it all relates to each other – hopefully it was a helpful exercise, and now they have a fun model to refer to (in Module 7 we will talk a lot more about genetics!).
To work on for next time:
- Enjoy fall break!
- start reading Module 6, answering the on your own questions as you go
- read experiment 6.1 and 6.2
Experiment 5.3 – The Fragility of an Enzyme:
We had 3 bowls of jello
- control: regular jello with no pineapple added
- room-temperature pineapple: jello with 1 Tbsp of the blended pineapple added
- heated pineapple: jello with 1 Tbsp of heated pineapple added
What is our expected outcome? How do you think the pineapple will affect the jello? Will heating the pineapple make a difference?
Results (see video):
- control: set as expected
- room-temperature pineapple: remained liquid, did NOT set
- heated pineapple: set just fine – no inhibition of setting detected
Conclusions:
- the enzyme in the fresh pineapple kept the jello from setting in the room-temperature pineapple jello
- the heat disrupted the enzyme and allowed the jello to set normally in the heated pineapple jello, matching the result from the control.
Video: Our experiment
Watch this video to understand more about what is happening in this experiment. Their experimental procedure is a little different than ours, but illustrates the same concept. There’s an excellent explanation of the biochemistry of the enzyme and how it is disrupted by heat starting at about the 2:30 mark.