FOR HEALTH SCIENCES
Term 1 2013
SUBJECT: BIOLOGY YEAR 11 HL & SL
Name of Student:
Name of Teacher:
FORMATIVE ASSESSMENT ITEM: Chemistry of Life Practical Investigation Term 1
Task: Investigation of a Factor Affecting Enzyme ActionAspects Assessed: D DCP CE MS Introduction:Thousands of enzymes are found in living cells. In addition to making life possible, many enzymes have numerous applications that affect our daily lives in other ways such as food processing, clinical diagnoses, sewage treatment, and the textile industry. In this activity you will investigate how a particular factor influences the action of an enzyme.Conditions: Students are NOT required to design an experiment. Experimental design has been provided for you to use instead. You are however required to submit a Risk Assessment for the investigation. Students are to work independently. However, you will need to collect raw data from 4 other students to make the 6 trials. The final version is to be submitted to TURNITIN and then class teacher.A journal will need to be included as part of the final submission. Time Allowed: 4 weeksDue Dates Task Out first lesson week1, term 1, 2013Risk Ass Due: last Lesson week 2, Term 1, 2013Final: First lesson week 6, Term 1, 2013Procedure: Your task is to investigate the effect of temperature on the activity of enzyme catalase found in beef liver. Use the experimental design and the BioLab Guide provided to assist with your report write up. Safety Considerations:You must have the risk assessment checked before continuing. NOTE: For this task you are required to submit a journal which documents your progress. You are also required to include photographs which display the techniques you used in the experimental procedures. This evidence will be used in assessing your manipulative skills in this experiment| RESULTS: REFER TO the Assessment Grading Matrix|
Effect of temperature on the activity of Catalase
Design Aspect 1:
This lab will be driven by the research question, Do changes in temperature (from 0˚C, 7˚C, 19˚C, 37˚C, and 100˚C) have an effect on the activity of the enzyme catalase (found in beef liver) in the breakdown of hydrogen peroxide? Hypothesis
If liver is placed in different temperatures of 0˚C, 7˚C, 19˚C, 37˚C, and 100˚C and hydrogen peroxide is added to each piece of liver, then the liver placed in 37˚C will have the largest reaction height. The liver in 100˚C will have the smallest reaction height, followed by the liver in 0˚C, then 7˚C, and then 19˚C.
Pearson Baccalaureate: Standard Level Biology Developed Specifically for the IB Diploma defines enzymes as “protein molecules which act as catalysts for reactions. As catalysts, the real function of enzymes is to lower the activation energy of the reactions that they catalyze” (166). Enzymes are proteins; therefore the liver has a particularly high concentration of catalase. When hydrogen peroxide (H2O2) is added to liver, catalase catalyzes a reaction in which the hydrogen peroxide is broken down into oxygen gas (O2) and liquid water (H2O). Hydrogen peroxide is a toxic chemical that is produced as a byproduct of many normal cellular reactions, so it is crucial that catalase in the liver breaks the hydrogen peroxide down into the two harmless substances of oxygen gas and liquid water. The hydrogen peroxide must be quickly degraded or converted, and catalase accomplishes this task because one molecule of catalase can deal with six million molecules of hydrogen peroxide in one minute. Enzymes and the temperature of their environment are particularly important to the human body because “Many of the reactions which represent the digestive process would...