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

The effect of Temperature on Enzyme Action (Rennin)

Extracts from this document...


The effect of Temperature on Enzyme Action (Rennin) Aim To investigate the effect of temperature on activity of Rennin Introduction Rennin is an enzyme secreted by walls of the stomach. It acts on a protein in milk causing it to pump into a semi-solid curd. The enzyme is readily available in the form of rennin solution. Enzymes are proteins that catalyze (i.e. accelerate) chemical reactions. In enzymatic reactions, the molecules at the beginning of the process are called substrates, and the enzyme converts them into different molecules, the products. Almost all processes in a biological cell need enzymes in order to occur at significant rates. Since enzymes are extremely selective for their substrates and speed up only a few reactions from among many possibilities, the set of enzymes made in a cell determines which metabolic pathways occur in that cell. Activity is also affected by temperature, chemical environment (e.g. pH), and the concentration of substrate. Some enzymes are used commercially, for example, in the synthesis of antibiotics. ...read more.


Also care has to be taken for the Bunsen burner because it may cause burn to the skin and also were protective gloves from hazardous chemicals. Variables Independent: - Temperature Dependent:- Is the rate of reaction(time taken for the milk to curdle). Control Variable:- Same amount of Rennin, same amount of milk, same concentration of Rennin, same type of milk and same amount of time the test tubes were left in water bath(5 minutes). Results Time taken for milk to curdle in the presence of Rennin Temperature Experiment 1 Experiment 2 Average 0�C Greater than 60min Greater than 60min (did not curdle) Greater than 60min 20�C Started to clot at 50 mins 35 mins 55 mins 40�C 2 mins 3.5 mins 2.75 mins 60�C Denatured Denatured 80�C Denatured Denatured Time taken for milk to curdle without the presence of Rennin Temperature Experiment 1 Experiment 2 Average 0�C Did not curdle Did not curdle 20�C Did not curdle Did not curdle 40�C Did not curdle Did not curdle 60�C Did not curdle Did not curdle 80�C Did not curdle Did not curdle Discussion questions 1. ...read more.


As temperature increases, so does the enzyme activity, up to a certain point. This is because as the temperature increases, the kinetic energy of the molecules also increases in the reaction, including the enzyme and this increase the speed of reaction decrease. However, after a certain maximum temperature, the enzyme's structure becomes irreversibly changed. After this, the enzyme is said to be denatured and enzyme activity drops rapidly. This is because the changed shape of the enzyme does not allow it to become involved in further reactions. The maximum point before denaturation is called the optimum temperature. This is when enzyme activity is highest. 9. The procedure used is a reliable way of investigating the effect of temperature on enzyme activity. However to get more reliable results, the experiment should be taken at shorter temperature intervals (e.g. 5-10�C) Conclusion Enzymes work best at optimum temperature. In the experiment, the optimum temperature was 40�C. This is because Rennin is produced by the walls of the stomach where the temperature is about 37�C. As temperature increase beyond the optimum, the enzyme activity decreases till it finally stops because enzyme is denatured. As temperature is decreased lower then the optimum, the rate of enzyme activity slows. ...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. What Effect Does The Temperature Of Water Used Have On The Rate Of Coagulation ...

    This results in there being more collisions between substrate molecules and the enzymes active sites and therefore more enzyme-substrate complexes are formed. This means the substrate molecules are broken up quicker and the reaction rate is therefore faster. This increase of reaction rate continues with the increase of temperature until

  2. Find out what effect different temperatures have on the enzyme, rennin, in milk.

    It is also similar to pepsin because it is most active in acidic environments, i.e. at a very low pH. Rennin is also a very important industrial enzyme because it is widely used in cheese making. In the past rennin was extracted from dried calf stomachs for this purpose but

  1. Investigate the effect of temperature on the action of rennin and milk.

    These are the results which I got: Temperature Time 10 Didn't breakdown 20 11 mins 30 6 mins 40 5 mins 50 6 mins 60 Didn't breakdown These results back up my prediction because at 40 the amylase takes 5mins so I predict that the rennin will also work best at 40.

  2. The aim of the investigation is find out the optimum temperature at which rennin ...

    at its limits and if it were to be pushed any further it would break down.

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