• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Catalase lab. This intent of this lab is to investigate how the factors of different pH levels and how they affect catalyze activity on the decomposition of hydrogen peroxide.

Extracts from this document...

Introduction

Sydney Berger Ms. O'Brien IB1 Biology B3 1st November, 2011 IB1 Biology Internal Assessment In terms of biology, an enzyme is a large protein molecule that speeds up or catalyzes chemical reactions found in nature. The intra- and intermolecular bonds that hold these proteins in their secondary and tertiary structures can be disrupted by changes in temperature and pH, and in some cases to the point where their catalytic activity can be destroyed (known as denaturation). All enzymes have an active site, and when a molecule has the correct shape and conditions it binds to one of the reacting molecules. The reacting molecule that binds to the enzyme is known as the substrate. The active site of an enzyme is where a substrate fits to initiate a reaction, or creating an enayme-substate complex as shown below. Catalase is an enzyme found in a variety of tissues of animals and plants that plays a role in the protection of cells. It destroys toxins introduced to cells, and this lab it will decompose the substrate hydrogen peroxide (??2??2) into two harmless products oxygen (??2) and water (,??-2.??). This intent of this lab is to investigate how the factors of different pH levels and how they affect catalyze activity on the decomposition of hydrogen peroxide. This entails measuring the height of the foam resulting from the amount of oxygen and water that the enzyme liberates from the reaction. ...read more.

Middle

5. Using a clean stirring rod, gently stir the ??2??2 solution and red potato with a slow, constant pace for one minute. 6. Immediately use a ruler to measure the height of the white foam from the initial height of the solution before the reaction occurred, to the top of the foam after one minute that reaction occurred. ((If you are not adding any pH solution, measure from the 20 mL mark (15mL of ??2??2 solution, 5 mL of red potato). If you are altering the pH of the ??2??2 solution, measure from the 23 mL mark (15mL of ??2??2 solution, 5 mL of red potato, 3 mL of pH solution.)) Record Results. 7. Dump solution in the waster container (NOT down the sink) and CLEAN the test tube (use test tube brushes) 8. To alter the ??2??2 solution, pour 3 mL of the desired pH solution (that is room temperature, ensured by using a thermometer prior) into the graduated cylinder of the initial 15 mL ??2??2 solution and thoroughly stir the mixture. 9. Repeat steps 1-8 using ??2??2 solutions but changing the pH level to 2, 4, 6, 8 and 10. Perform 5 trials for each different level. Raw Data- Qualitative- As the lab was being performed, qualitative observations included the most bubbles formed the quickest around the pH levels of 6 and 8, and the bubbles were very dense and thick. ...read more.

Conclusion

Also I did the best I could to control the temperature of all of the materials and keep them constant, but when I could not record the temperature there could have been slight variations that could alter the result, considering catalase is sensitive to temperature change. As a limitation using a wide range of pH solutions would give a broader prospective of how varied pH levels of a substrate truly affect catalase activity, however the recourses were not present at the time. If I had access to more than 5 different pH levels, the extra data points would establish a stronger support for the quadratic relationship. Anomalies that I had encountered included separation of the solid and liquid of my Red Potato catalase Source, and knowing that if I tried to react and un-mixed catalase source, my results would probably be less effective and have less foam. To minimize these adverse effects, I paid critical attention to my catalase before each trial and was constantly stirring it back to its original condition. All in all, the experimental design did answer my research question and had minimal adverse results due to poor lab techniques. The reliability of my data corresponds with my background information, and provides stable evidence with quantitive and qualitative data to support. Suggestions for Improvement 1) A larger range of pH solutions to alter the H202 solution would establish a stronger relationship. 2) Using an O2 detector could provide a more accurate detection of the oxygen liberated from the reaction. Resource of Picture: http://www.rsc.org/Education/Teachers/Resources/cfb/enzymes.htm 1 Berger ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our International Baccalaureate Biology section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related International Baccalaureate Biology essays

  1. Marked by a teacher

    Osmosis Internal Assessment (Biology)

    4 star(s)

    The difference between the two was 0.3 grams while the differences between the one hour intervals for all the other time intervals was only 0.1 grams, and after processsing the raw data, mean percent change of the mass of the potato strip at 2 hours did not fit in graph

  2. Design Lab

    more beats per minute. The reason as to why I think that this is going to happen is that house music is a type of music that has a strong beat and generally gets people motivated and moving. We associate house music with dancing and jumping up and down, and for that reason I

  1. Biology Lab Report-Osmosis

    the potato cell, then water from the potato cell will move out into the solution, through the semi-permeable membrane by osmosis. This means that each cell of the potato chip will decrease in size and mass as water leaves the cell.

  2. Investigating an enzyme-controlled reaction: catalase and hydrogen peroxide concentration

    2H2O2 ==> 2H2O + O2 My hypothesis was right. As the concentration of hydrogen peroxide increased, the rate of reaction also increased. This is because more substrates could react with more active sites of the enzyme when the concentration of hydrogen peroxide increases.

  1. Influence of pH on the activity of potato catalase

    Cut cylinders of potato tuber. 3) Cut 60 discs 1 mm thick and put them under water 4) Construct the apparatus shown on the Drawing 1. 5) Place 5 cm3 of buffer solution at pH 3.0 6) Dry the potato discs 7) Place 10 discs in the solution 8)

  2. Investigating the effect of pH of Hydrogen Peroxide upon the activity of Catalase

    -computer with scientific software -bunsen burner -tripod stand/thermometer Method: First, the Catalase from the chicken liver will be obtained. It will be cut up with a scalpel and measured by a ruler to 5 pieces of 1cm� and weighed with the weighing machine so that it weighs 0.5g.

  1. Biology Internal Assessment Soil pH

    Find out the average for both the moisture soil and dry. Afterwards find out the average for the length of the Viola tricolor in different soil as well. 6.) Return the soil back to where you took it from originally.

  2. What is the effect of increasing pH concentration (pH 3, 4, 5, 6 and ...

    This was done to ensure that all the seeds get enough space to grow and was growing in the same environmental conditions. * All the seeds were exposed to the same temperature, and the Oâ level.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work