Final Applied Lab Project (1 credit Lab Component)
Addresses course
outcomes 1-4:
·
recognize and explain how the scientific method is used to solve problems
·
make observations and discriminate between scientific and pseudoscientific
explanations
·
weigh evidence and make decisions based on strengths and limitations of
scientific knowledge and the scientific method
·
use knowledge of biological principles, the scientific method, and
appropriate technologies to ask relevant questions, develop hypotheses, design
and conduct experiments, interpret results, and draw conclusions
This is the culminating lab
assessment in BIOL 103. It is designed to assess your ability to apply the
principles of the scientific method.
The Effect of low pH on Enzyme Activity
Design an experiment in which
you will test the effect of an acidic fluid on enzymatic activity. Recall:
enzymes are proteins! To complete this project, it may be useful for you to
first review the Scientific Method Tutorial, the OLI module about pH and
enzymes, Lab 1 (Introduction to Science) and Lab 4 (Enzymes). As you
review Lab 4, you will be reminded that there are several factors that impact
enzymatic activity: pH, temperature, and amount of reagent. It is OK to
use the same enzyme/substrate/method as you did in lab 4 (but modify the
treatment), or you can search on-line to find a different
enzyme/substrate/method for measuring enzyme activity for your project (include
all references).
As you design your experiment
for this project, please remember that you are trying to examine how anacidic fluid will modify the outcome
of an enzymatic reaction. To successfully complete this project, you will
need to identify the question(s) being asked in your experiment and the
hypothesis that you are testing. In your experimental design, you must
clearly explain what you are doing. That means that you will need to
identify the enzyme, the substrate, the acidic fluid used as treatment, the
control treatment and the method of measuring enzyme activity, as well as explain
your experimental protocol. You must also thoroughly explain how the
acidic fluid impacted enzyme activity based on the results from your own
experiment as well as knowledge of enzymes and pH from the OLI modules, lab
manual and potentially additional information sources.
Hint: Keep in mind that the acid will change the environmental conditions
of the experiment (for example, a low pH value could change the shape of the
active site on the enzyme protein), without directly participating in the
reaction.
Lab Materials
Youmay need all or some of the
following, depending on your experimental design:
Materials from your lab kit:
·
pH paper
·
hydrogen peroxide solution (you can purchase this at a pharmacy if you have
used up the bottle that came with the lab kit)
·
plastic beakers or cups
·
vinegar
·
yeast (can be purchased at grocery store if more is needed)
·
balloons
·
plastic bottle
·
marker for labeling of beakers
You may choose to use
additional materials (different acidic fluids and/or different organisms and/or
different substrate if you chose an enzyme other than catalase).
Outline submit in assignment folder in week 5.
Include the following in your
outline:
·
Name of enzyme you will use
·
Name of organism (if applicable)
·
The substrate
·
Method for measuring enzyme activity
·
Treatment: acidic fluid(s), pH, length of exposure, how you will treat your
samples
·
The control(s) in the experiment
·
Sample size
·
Hypothesis
·
How you will present your data (table and/or type of graph)
·
Anything else you would like to get feedback on before you start your
experiment
Write a paper that includes the following:
1. Title page: descriptive
title, your name, course name, semester
2. Introduction: general
background information about enzymes and specific information about your chosen
enzyme, the question(s) that you are asking and a clear hypothesis for your
experiment (20 points).
3. Design an experiment.
Provide a detailed description of the materials and methods used to conduct the
experiment. Identify control and experimental samples, as well as independent
and dependent variables. Also include the methods used for data collection and
analysis (20 points).
4. Conduct the experiment and
record your results. What did you observe? Present your data in table
and/or graph format. Remember to label everything and include the unit of
measure with all numbers (20 points)
5. Use your knowledge of
enzymes and pH to interpret and discuss your results. It may be necessary for
you to refer to the OLI course modules, lab manual and/or use additional
information resources. What effect does the acidic treatment have on
enzyme activity? Did you get the expected results? Explain. (20 points)
6. State a specific and
accurate conclusion. Is your hypothesis supported by the results? Looking back,
how could you have improved your experiment? (10 points)
7. Include a list of
references to all information sources used in APA format (5 points).
