{"id":1339,"date":"2020-04-21T11:36:04","date_gmt":"2020-04-21T15:36:04","guid":{"rendered":"https:\/\/wordpress-projects.wolfware.ncsu.edu\/bio-183-lab-yhnn8gz\/?page_id=1339"},"modified":"2023-05-10T21:21:39","modified_gmt":"2023-05-11T01:21:39","slug":"unit-2-labs-2-3-online","status":"publish","type":"page","link":"https:\/\/wordpress-projects.wolfware.ncsu.edu\/bio-183-lab-yhnn8gz\/unit-2-labs-2-3-online\/","title":{"rendered":"Unit 2: Labs 2-3 Enzyme Lab – In Person Labs"},"content":{"rendered":"\n

Properties of Enzymes (2 weeks of lab) –<\/span> In Person Labs<\/span><\/span><\/h2>\n\n\n\n

Scroll below for In-person Labs<\/span><\/h4>\n\n\n\n
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Click for Online Make Up Module<\/a><\/div>\n<\/div>\n\n\n\n

Enzyme Lab Handout (covers 2 weeks of In-Person labs)<\/a> \u2013 Includes areas for filling out your tables and answering questions. <\/span><\/p>\n\n\n\n

Make sure you have Excel or access to Google Sheets.  As an NCSU student, you can download Microsoft Office 365 from NC State\u2019s OIT<\/a> software site for free!<\/span><\/p>\n\n\n\n

Read along in your Enzyme Handout as you work with the information in this webpage.  Fill in and answer questions accordingly.  Your Enzyme Handout will be collected and graded later.<\/em><\/span><\/h4>\n\n\n\n
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\"Enzyme<\/figure><\/div><\/div>\n\n\n\n
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\"Effect<\/figure><\/div><\/div>\n<\/div>\n\n\n\n

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How Cells Work – Enzymes<\/a><\/h3>\n\n\n\n

Chemical Reactions and Activation Energy<\/h3>\n\n\n\n
\"Graph<\/figure>\n\n\n\n

Catalase<\/h3>\n\n\n\n
\"Catalase<\/figure>\n\n\n\n

Animation – Enzyme Function and the difference between competitive and non-competitive inhibitors.<\/a><\/h3>\n\n\n\n

Activity 1: Qualitative Study of Catalase <\/span><\/h3>\n\n\n\n

2H2<\/sub>O2<\/sub> + catalase —-> 2H2<\/sub>O + O2<\/sub> + catalase<\/span><\/span><\/h3>\n\n\n\n

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Catalase is prepared by blending a potato in cold water, then filtered by straining the mixture through 4 layers of cheesecloth.  The catalase solution is then kept cold on ice.  Why would filtering and maintaining a cold temperature be important for the catalase solution?<\/span><\/p>\n\n\n\n

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Procedure A Testing the Activity of Catalase <\/span><\/h3>\n\n\n\n

Follow steps 1-3 and complete Table 1 using the results from your 4 prepared test tubes.  The picture below shows the appearance of catalase and boiled catalase used Procedure A.  What would account for the difference in appearance of the boiled catalase?  Where did the “chunks” come from?  <\/span><\/p>\n\n\n\n

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Procedure B Testing the Activity of Catalase Under Six Different Environmental Conditions <\/span><\/h3>\n\n\n\n

You will be assigned to work with ONE of the six environmental conditions (Groups) below.  Propose a plausible hypothesis for your assigned experiment.  The same basic reaction as tube #3 in Procedure A is followed, but treated with an assigned environmental condition.  Answer all questions and fill in the Table that corresponds to your assigned<\/em> treatment in your lab manual (Tables 2 – 7).   <\/strong><\/span><\/p>\n\n\n\n

Your assigned Group for Procedure B will be the same Group assignment for Procedure D performed in lab Enzyme Week 2.<\/strong><\/span><\/p>\n\n\n\n

Group I: Effect of Substrate Concentration on Catalase<\/td>Group II: Effect of Hydroxylamine and Subs. Concentration<\/td><\/tr>
Group III: Effect of Salt Concentration on Catalase<\/td>Group IV: Effect of the Metal Copper Sulfate<\/td><\/tr>
Group V: Effects of pH on Catalase<\/td>Group VI: Effect of Temperature<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

Activity 2: Quantitative Study of Catalase <\/span><\/h3>\n\n\n\n

2H2<\/sub>O2<\/sub> + catalase + guaiacol (colorless) —-> 2H2<\/sub>O + catalase + tetraguaiacol (orange-brown)<\/span><\/h3>\n\n\n\n

We can study the same reaction as above in a more detailed manner by fine tuning the experiment.  Instead of learning about the relative activity of catalase, observing more or less reaction, we can introduce a sensitive color indicator to detect the presence of one of the reaction products.  The color indicator guaiacol will change from clear to orange-brown as it binds to the O2<\/sub> produced in this reaction forming tetraguaiacol.  This color change can be measured using a spectrophotometer.  These data can then be graphed and rates determined for the baseline reaction of catalase, but also for the various treatments.<\/span><\/p>\n\n\n\n

Procedure C Using a Spectrophotometer to Monitor Baseline Catalase Activity <\/span><\/h3>\n\n\n\n

Carefully read the Procedure C background.  This will help you fill in and answer Procedure C questions and Table 8 & 9 in within in your lab handout.  <\/span>We will use a Genesys spectrophotometers and square disposable cuvettes.  If you have not used a spectrophotometer before, view the videos below.  It is very important to use an appropriate blank for each treatment that is run.  The blank will contain all the same components as the treatment tube, minus the enzyme.  This way we will know that any change in color is resulting from the activity of the enzyme itself.<\/span><\/p>\n\n\n\n

How spectrophotometers work<\/a> – transmittance and absorbance<\/h3>\n\n\n\n

How to use a Genesys 10 Spectrophotometer<\/a><\/h3>\n\n\n\n

Determining  Baseline data<\/strong><\/span> – Follow directions in Procedure C to collect quantitative data.  Then create a graph monitoring the baseline catalase reaction.  Be sure to label the graph correctly with all appropriate graphing components outlined by your TA and indicated in the Resources –> Appendix D: Graphing Using Excel.<\/span><\/p>\n\n\n\n