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

The aim of the experiment is to investigate the effect of temperature on the activity of trypsin, using a suspension of casein as the substrate.

Extracts from this document...

Introduction

Aim: The aim of the experiment is to investigate the effect of temperature on the activity of trypsin, using a suspension of casein as the substrate. Hypothesis: Enzymes are substances that act as catalysts, in other words they increase the rate of chemical reactions. In biological system, this reaction might occur very slowly, or not at all, in the absence of an enzyme. Enzymes will greatly increase the rate of formation of the product. Enzymes can increase the rate of reaction by a factor of at least one million. Most enzymes are large protein molecules, with complex three-dimensional shapes. This diagram shows the complex 3D-structure of trypsin. Trypsin is an enzyme that acts to degrade protein; it is often referred to as a proteolytic enzyme, or proteinase. Trypsin is one of the three principal digestive proteinases, the other two being pepsin and chymotrypsin . In the digestive process, trypsin acts with the other proteinases to break down dietary protein molecules to their component peptides and amino acids. Trypsin continues the process of digestion (begun in the stomach) in the small intestine where a slightly alkaline environment (about pH 8) promotes its maximal enzymatic activity. Trypsin, produced in an inactive form by the pancreas, is remarkably similar in chemical composition and in structure to the other chief pancreatic proteinase, chymotrypsin. ...read more.

Middle

Enzymes work best at around body temperature. This is how I expect the graphs to look during the experiment. Graph 1. Graph 2 Optimum Temp Rate of Reaction Time/ Min Temperature/ �C Temperature/�C The first experiment to take place was with two other enzymes and they were pepsin and protease. However, during the experiments, the pepsin and protease were working with the casein substrate at a very slow rate, so doing the experiment with the protease and pepsin would have been very time consuming. The point of doing trypsin, pepsin and protease was to make a comparisons about their optimum temperature. So I carried out the experiment just looking at the effect of temperature on the enzyme trypsin. I used trypsin at 0.5% molar concentration because if I were to anymore the reaction would go quick and if I was to add any less, it would be very slow. I also used to 4% molar concentration of casein because if I was to use too much, there would more interactions and therefore the experiment would finish quickly. If I used to little the amount of interactions would be slow so the experiment would be slow. Method: Apparatus: 1.Casein Suspension, 4% 2. Trypsin solution, 0.5% 3. Distilled water 4. ...read more.

Conclusion

The following are precautions taken whilst doing the experiments to decrease the level of inaccuracy: - The equipment was well washed so that any impurities could be washed off and therefore not contaminate the water and the solution, which may alter the optimum temperature of the enzyme and change my results. I did not hold the thermometer as I would conduct heat into the thermometer and alter the readings so therefore it was left to stand in the beaker. To get a more accurate set of results, using shorter temperature intervals would show me the optimum temperature more clearly. I was using 5 �C if was to use a 2 �C I think I would get a more accurate set of results. Also, the concentration of trypsin, if it was changed it could show the optimum temperature more accurately. The experiment, with an increased amount of trypsin concentration, would have gone faster. The following sources errors, in my opinion have affected my results, they are: - The rounding up of temperatures and measurements. A lot of the heat could have been conducted into the desk from the beaker, causing our temperature readings to fluctuate. Some of the heat could have been radiated away. Also some of the heat heated up the thermometer therefore maybe a digital thermometer could have been used or maybe a calorimeter to get an accurate reading of the temperature. Also some the heat may have been lost by convection currents. ...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 Molecules & Cells 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 Molecules & Cells essays

  1. Marked by a teacher

    Investigating the effect of enzyme concentration on the activity of cellulase.

    5 star(s)

    Then to try to find the optimum or best substrate concentration that will give a viscosity that will flow through the syringe barrel within the time constraints (maximum 10 minutes for the substrate to flow through)

  2. Marked by a teacher

    The Effect Of Temperature On Trypsin Enzymes

    3 star(s)

    - For more reliable results repeat the experiment three times. Apparatus and diagram - Beaker containing trypsin. - Beaker containing milk. - Measuring cylinders. - Large beaker of water. - Test tubes. - Test tube holder. - Test tube rack.

  1. Marked by a teacher

    Enzyme concentration and enzyme activity. Trypsin

    3 star(s)

    There were many factors, which could have affected the results of my experiment. The main source of error was judging if the solution had turned clear. It was impossible to judge the point whether the solution had purely turned clear with naked eyes, causing the results to be unreliable.

  2. Marked by a teacher

    Enzyme concentrations using trypsin enzume and casein solution

    The 1% trypsin worked best because the active sits of the enzyme molecules are still free and are able to be a site for the substrate to react. Whereas, with a lower concentration, there are less active sites to accommodate all the reactions, saturated.

  1. Investigating the effect of temperature on Trypsin enzymes.

    In the main experiment, I will conduct the experiment at the following temperatures (?C): 15, 25, 35, 45, 55, 65, and 80. I will only go as far as 80?C because at this temperature I expect that the temperature will have denatured all of the enzymes.

  2. Investigate the effect of enzyme temperature on the activity of the enzyme Trypsin on ...

    This transition state has a higher energy level than either the substrates or the product. Outside the body, a lot of heat is used to initiate the reaction. However, this is dangerous inside the body, so we have enzymes that an alternative way with a different transition state and lower activation energy.

  1. An experiment to find of the isotonic point of root vegetables cells in contents ...

    This is what caused the carrot cell to decrease in length and width at this concentration. The beetroot was placed in sucrose solutions with molarity of 0.6, 0.65, 0.7, 0.75 and 0.8. The beetroot placed in sucrose solution with molarity of 0.6 and 0.65 had an increase in mass, width

  2. An Investigation Into the Effect of Substrate Concentration On the Rate of Enzyme Activity.

    9 8 8 60 7 7 6 8 7 7 7 70 12 15 12 14 13 12 12.5 80 did not rise after 60 seconds Table 8: 1/T - The Effect of Temperature on the Activity of Catalase and median 1/T (Free Enzyme)

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