Description
Introduction: Week 2: Enzyme Lab
In this activity, you will study the effect of pH, temperature and lactose concentration on lactase activity. By the end of this activity, you should be able to:
design experiments to study the effects of pH, temperature, and substrate concentration on enzyme activity.
graph data related to enzyme activity.
analyze data related to enzyme activity.
complete a lab write-up summarizing and analyzing your results for the effect of temperature on lactase activity.
identify the components of the scientific method.
identify components of the substrate-enzyme-product system being studied.
Before beginning this activity, make sure you are comfortable with the concepts of independent and dependent variables, experimental and control groups, and hypothesis. You will be applying these concepts in this lab, plus in many of the future labs. To prepare for the lab, watch the following
video
(Links to an external site.)
and think about enzymes, substrates, products, maximum rate of reaction, and optimal conditions.
(Links to an external site.)
We will work through Experiment I, testing the effect of pH on enzyme activity, together during our
Zoom lecture
(Links to an external site.)
. You will then individually use what we did together as a model to design data collection tables and study the effect of temperature and the effect of lactose concentration on lactase activity (Experiment II and Experiment III). Please note, this requires that you totally understand what we are doing while we are together in our Zoom session. You will take this understanding and apply it in a slightly different experiment to complete Experiment II and Experiment III. Experiment IV requires you to look at the materials and methods available to you in the simulation to determine if you can study the concept of enzyme specificity using the website.
You will need to produce graphs using Excel or Google docs. I will not accept hand-drawn graphs or photographed images. If you are unsure how to do this, it is fine to work with other students. The final product must be your own work, but it is a good strategy to help out others in the lab.
To complete the lab activity, go to the following website (
https://sites.google.com/site/biologydarkow/lactase-enzyme-simulation
(Links to an external site.)
and read through the Home, Background and Explore the Model tabs.
You will produce a lab write-up on the effect of temperature on lactase activity. Note, you are focused on Experiment II and should use the data from that activity only for the write-up. Your understanding of Experiments III and IV will be assessed in a different format during Week 3.
I will provide you an outline of how to organize and what to include in your write-up, but your report should be in nonnumeric, paragraph form. This outline is found in the Week 2 module.
Submit your lab write-up by 1159PM this Sunday (Week 2) using Canvas. We will use this lab write-up as a major part of Week 3. By 9AM Tuesday of Week 3, you will be provided with comments and feedback from both the instructor and Peers. You should make changes based on these comments and feedback (or inspirations which come to you outside of this exercise) to improve the write-up. You must resubmit your lab writeup prior to 11:59 PM next Sunday (Week 3) even if you do not make changes. If you do not submit an assignment, you will receive no points. Lab for the Week 3 will consist of providing comments and feedback to your peers and reworking your lab report. We will not be doing the osmosis lab that week. This will be done utilizing the Week 3 lab module.
