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

An experiment to investigate the effect of temperature on the action of the enzyme lipase.

Extracts from this document...


An experiment to investigate the Effect of Temperature on the Action of the Enzyme Lipase Introduction In this experiment I will be investigating how temperature affects the rate of reaction of enzymes (lipase) on substrates (fats). This investigation will allow me to gain a greater knowledge of enzymes and how they work. In this experiment I will only be investigating one factor that affects the action of enzymes. The other factors that might affect the action are the concentration of the enzyme and the concentration of the substrate. According to how concentrated the enzyme or substrate is, it will affect the rate of reaction as a higher concentration of enzymes may make the rate of reaction quicker. (Although we have to take into account the ratio between enzymes and the substrate, as having a too high concentration of the substrate may not affect the rate of reaction). Also if there is a lower concentration of substrate, then the rate of reaction may speed up. To understand how the temperature might affect the rate of reaction, we have to see how enzymes work, especially lipase. Here is an equation that gives the general outline to it. FAT........................... FATTY ACIDS + GLYCEROL Enzymes have an active site in which they break down the substrate. I will talk about this in my conclusion and my evaluation. The method I am going to use will help gather results from different temperatures to which the enzymes are exposed to and will enable me to draw a graph. From this I can gather more data on the effects of temperature on enzymes. I will give a detailed method further on in my planning. I predict that the temperature for optimum enzyme activity will occur 40�C-45�C. It is known that every enzyme has an optimum temperature and breaching this means denaturing the enzyme. When the temperature gets higher, there is enough energy to break some molecular bonds in the enzyme. ...read more.


Enzymes have factors that affect the rate of reaction. They are the concentration of the lipase, the concentration of the substrate and the temperature. I investigated the temperature. To understand how the temperature affected the rate of reaction and gave me the results I achieved, I need to see what enzymes are and how they work. An enzyme is a biological catalyst that speeds up reactions without chemically changing itself. They have an active site that connects the substrate and the enzyme together. It is here that the enzyme breaks the substrate down, making it easier for it to be absorbed into the blood stream. Here is a diagram of the enzyme breaking a substrate down. This diagram shows what is happening to the fat in the milk. When an enzyme is not present, there is an energy barrier preventing the molecules in a cell from reacting more than occasionally to form products. An enzyme gives more chance of this happening by temporarily combing itself with the molecules of the substrate and making them more reactive. In this way, if there is more heat then the molecules will work faster as they have more energy. At higher temperatures this happens, but if the temperature exceeds the optimum temperature a lot, then something different happens. The reason for the reaction going slowly at a temperature below 50�C is because there was enough energy at such a low temperature, even if there was an enzyme there. At temperatures above the optimum temperature, which were different in my graph, the enzyme became denatured. The rate was higher at the higher temperatures (up to 50�C) because as the temperature is raised, so is the energy level of the enzymes and substrate molecules. This is where the greatest number of collisions takes place between the enzyme and the substrate and therefore the highest rate of reaction is. This means that they have more kinetic energy so they collide more often and therefore more reactions take place between them. ...read more.


I could find out the lowest temperature recorded of a human being, and try and see how it affects the rate of reaction of the lipase. Also, this could be tried with different types of enzymes, for example using potato discs with amylase. This experiment helped me to learn a lot more about enzymes and how the function under some circumstances. It also helped me to learn how I can improve my obtaining results section. Although it was almost a suitable method, the fact that I obtained anomalous results shows that it was not that reliable. Also many people did not get accurate results, as the equipment used did not allow us to acquire accurate results. It is important that we find out about enzymes and their actions as we use them in our everyday lives. Apart from living in our bodies and breaking up large molecules, enzymes are used for other important things. These are included in industrial and medicinal. They are needed for the fermenting of wine, leavening of bread, curdling of cheese, and brewing of beer. In medical usage, they include the killing of disease-causing microorganisms, the promotion of wound healing and the diagnosis of diseases. They are also needed for washing-up powder, to break down food stains, and also to be synthesised to produce more enzymes for people who cannot manufacture it themselves. If wee do not understand enzymes, then we will not be able to use them when we need to do. This would cause us to fall back in our progress in science. As well as these reasons, we use enzymes everyday and so we need to understand how they work so we know where to use them. They are also living inside us and many people like to know what is going inside themselves. This investigation was very helpful and informed on new things that involve enzymes. It also helped me to see that changing the temperature will affect the rate that the enzyme breaks down the substrate, which affects our body. 1 Ambareen Naqvi 10K ...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

    The Effect of Substrate Concentration on Enzyme Action.

    4 star(s)

    A small number of the amino acids make up the enzymes active site. This is the part of the enzyme where a substrate will fit forming an enzyme substrate complex. The products are released from the active site leaving the enzyme free to combine with another substrate.

  2. for this experiment my main aim is to investigate the effect of temperature on ...

    temperature of Catalase affects the breakdown of hydrogen peroxide, although there were some limitations and minor errors which must have contributed to some of the inaccuracies in my results. Most of the errors that contributed to the inaccuracies in my experiment came from the experimental procedures.

  1. An Experiment to investigate the factors that affect the Power Output of a solar ...

    That is the pattern. When it was 80 cm away from the light, the solar cell with the red filter produced a power output of 22.5 milliwatts, the solar cell with the green filter produced a power output of 8.1 milliwatts and the solar cell without any filter produced a power output of 44.1 milliwatts.

  2. Investigating The Activity Of The Enzyme Lipase On Milk

    The higher the temperature, the more collisions occur between enzyme and substrate, which means there is more change of an enzyme binding with the correct substrate to complete the Lock and Key Hypothesis more rapidly. When a certain temperature is reached, enzymes will denature and no longer be able to fit substrate molecules into them.

  1. An experiment to investigate the effect of enzyme concentration on the rate of milk ...

    ==> How enzyme concentration must be kept accurate: We are using different enzyme concentrations in this reaction so even though they are not being kept constant they must be accurate. The source of the lipase enzyme must remain constant due to possibly more or less impurities possibly acting as inhibitors therefore causing anomalies.

  2. Comparing the effect of different temperatures on free lipase and immobilised lipase

    This is because the molecules have increased kinetic energy, hence more collisions between the substrate and enzyme molecules. However, temperatures over about 45�C break the links that hold the enzyme molecules in shape. An increase in temperature after this causes the destruction of the tertiary structure of the enzyme protein thus destroying the native sites.

  1. How temperature affects the activity of lipase

    The substrate molecule fits into the active site of the enzyme molecule like a key fitting into a lock (in fact it is sometimes called a lock and key mechanism). Once there, the enzyme changes shape slightly, distorting the molecule in the active site, and making it more likely to change into the product.

  2. See if the concentration of the substrate (milk) will effect the rate at which ...

    I thought this because the less fat particles there are, the less work the enzymes have to do. However, this is not the case because the more fat particles there are, the more chance there is of an enzyme bumping into it.

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