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

Enzyme_Concentration_and_Enzyme_Activity

Extracts from this document...

Introduction

Enzyme Concentration and Enzyme Activity Aim: The pancreatic duct in individuals who have cystic fibrosis frequently becomes blocked, reducing or preventing the release of pancreatic enzymes into the small intestine. The aim of this activity is to investigate the effect of a reduction in enzyme concentration on the rate of reaction, in this case the breakdown of sucrose by sucrase enzymes. Hypothesis: I predict that an increase of concentration levels of substrate will catalyse the rate of reaction up to a point whereby any further increase in concentration produces no significant change in the rate of reaction as result of the enzyme reaching their active peak. Null Hypothesis: There will be no relationship found between the concentration levels of enzyme and substrate and the rate of reaction. Rationale: Enzymes play key roles in an experiment where they are used to catalyse a reaction. Enzymes can speed up the breaking down of molecules, like protein, into smaller ones. Others can speed up the building of large molecules out of small ones. They do this by lowering the energy needed for the chemical reaction to occur, the energy needed for the chemical to occur is also known as the activation energy. Without the enzyme, the activation energy needed for the reaction to proceed is high and vice versa. ...read more.

Middle

The enzyme can also be affected by the pH, if it's too high or too low the active site will, again, change shape, resulting in a lower rate of reaction.T Method: - Equipment list: - * Standard acidified sucrase solution. * Gelatine jelly. * Standard laboratory glassware, beakers, test tubes etc. * A ruler * Stop clock * Thermometer * Pen and paper. Variables: - * Independent variable: - My independent variable is the different concentrations of substrate. * Dependant variable: - My dependant variable for this experiment is the measurement of the rate of reaction in different concentrations. * Control variables: - My control variables are the variables that I need to keep the same to make sure that this experiment is a fair test. These are: - 1. The temperature. It is important that I control this as this will denature the enzymes. 2. pH. It is important that I control this as this will denature the enzymes. 3. Time that the mixture is in the beaker before and during the experiment. Procedure 1. Half fill a glass beaker with water to act as a water bath. Adjust its temperature to between 35 C and 40 C. (Note: Using a Bunsen burner may force the temperature of the water to rise a few degrees above the stated temperature after the burner has been taken away.) ...read more.

Conclusion

Results Test tube Sucrose Concentration / g dm3 Time (secs) Observations A 5 363.6 Light green B 10 87 Light yellow C 15 76.2 Yellow D 20 67.2 Light Orange E 50 45 Orange F 100 44 Orange/Red Below are the relative rates of cloudiness formation. I have worked this out by dividing 100 by the time taken in seconds for each tube as follows: Relative rate of cloudiness formation = 1000 T Test tube Sucrose Concentration/ g dm3 Relative Rate of cloudiness. A 5 2.75 B 10 11.49 C 15 13.12 D 20 14.88 E 50 22.22 F 100 22.73 Graphs Conclusion In this experiment, my results show that as the concentration of sucrose increases then the rate of reaction decreases. This suggests that as an increase in substrate is added the enzymes can not catalyse these as they have reached their active peak. The graph shows this as a steady curve. This then backs up my hypothesis and disproves my null hypothesis. Evaluation To improve this experiment I would have to increase the number of tests to see if my results are repeatable and accurate. I would also want to make sure that the timing was quicker when adding the Benedict's solution so that each tube would get the solution in a much shorter time to avoid anomalous results. I would also take more care when conducting the experiment to ensure that there can be no random errors produced. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our AS and A Level Energy, Respiration & the Environment 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 AS and A Level Energy, Respiration & the Environment essays

  1. Marked by a teacher

    Effect of nitrate concentration on the growth of Duckweeds

    5 star(s)

    Potassium is a cofactor that functions in protein synthesis, it also aids processes such as active transport and major solute functioning in water balance. The yellow colour obtained is because there was a shortage in chlorophylls which means that there is less light energy trapped due to fewer amounts of

  2. Marked by a teacher

    Fighter Pilot A Statistical Analysis of Reaction time and its Correlation with Dominant ...

    5 star(s)

    If this investigation were it to be repeated these variables may need to be considered. The next point observed while doing the experiment which may have caused some short comings was the area chosen for the experiment, the student's union, a rather noisy area with many people coming and going.

  1. Investigating the effects of Sodium Hydroxide concentration on Catalase

    you have a longer time to do it, you would do more to the investigation to get more relievable results, also the chemical you use and the apparatus you use because of being a school they can not have the really strong chemicals nor can they afford to have the

  2. the effect of bile concentration on the activity of the enzyme lipase during the ...

    Subsequently even though the enzyme has a certain basic shape it becomes slightly different as it alters its shape in the presence of the substrate to put strain on the substrate molecule and thereby lower its activation energy. By telling us how enzyme works we can be able to get a clearer understanding of what is occurring during our experiment.

  1. Investigate the effect of bile salt concentration on the digestion of milk by the ...

    This is called the lock and key mechanism. Alternatively, the substrate may be a slightly different shape and because the enzyme contains some flexibility it may be induced to change its shape slightly to fit in the molecule. However, an enzyme is specific for its substrate and only works to catalyse that reaction.

  2. To investigate how concentration of the enzyme catalase in celery extract affects the rate ...

    Material from - http://s-cool.co.uk In order for particles to react, they need kinetic energy. Reactant must collide, but only a certain fraction of the total collisions, the effective collisions, cause the transformation of reactant molecules into products. This is due to the fact that only a fraction of the molecules

  1. Investigating the effects of different lead chloride concentrations on the growth of cress seedlings

    Water then moves into the cell by osmosis to re-establish the osmotic balance. This increases the turgor of the guard cells and the stomata opens allowing gasses to enter the tissue. ABA will close the stomata very quickly. It is not known how exactly ABA achieves this, however is thought

  2. Effect of Concentration of Enzyme on the Rate of Reaction

    The diagram below shows the energy profile of decomposition of hydrogen peroxide with and without catalase. (467 words) Also, catalase is not used up in the decomposition of hydrogen peroxide. After catalyzing the reaction, the enzyme is still available to bind with another hydrogen peroxide molecule.

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