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

Factors Affecting Enzyme Activity.

Extracts from this document...

Introduction

Factors Affecting Enzyme Activity! Reactions proceed because the products have less energy than the substrates. However, most substrates require an input of energy to get the reaction going, (the reaction is not spontaneous). The energy required to initiate the reaction is called the activation energy. When the substrate(s) react, they need to form a complex called the transition state before the reaction actually occurs. This transition state has a higher energy level than either the substrates or the product. Outside the body, high temperatures often supply the energy required for a reaction. This clearly would be hazardous inside the body though! Fortunately we have enzymes that provide an alternative way with a different transition state and lower activation energy. The rate of the reaction without any external means of providing the activation energy continues at a much faster rate with an appropriate enzyme than without it. The maximum rate that any reaction can proceed at will depend, among other things, upon the number of enzyme molecules and therefore the number of active sits available. ...read more.

Middle

As the enzyme concentration increases, there are more active sites and the reaction can proceed at a faster rate. Eventually, increasing the enzyme concentration beyond a certain point has no effect because the substrate concentration becomes the limiting factor. 4. Substrate concentration: at a low substrate concentration there are many active sites that are not occupied. This means that the reaction rate is low. When more substrate molecules are added, more enzyme-substrate complexes can be formed. As there are more active sites, and the rate of reaction increases. Eventually, increasing the substrate concentration yet further will have no effect. The active sites will be saturated so no more enzyme-substrate complexes can be formed. Inhibitors Inhibitors slow down the rate of a reaction. Sometimes this is a necessary way of making sure that the reaction does not proceed too fast, at other times, it is undesirable. Reversible inhibitors: Competitive reversible inhibitors: these molecules have a similar structure to the actual substrate and so will bind temporarily with the active site. ...read more.

Conclusion

For example NAD, which transfers hydrogen away from one molecule in a dehydrogenase reaction and takes it to another molecule (see the Respiration QuickLearn). 2. Metal ions - most speed up the formation of the enzyme-substrate complex by altering the charge in the active site e.g. amylase requires chloride ions, catalase requires iron. Examples of the industrial uses of enzymes Perhaps the best known use is that of protease in biological washing powders. This enzyme helps to break down protein stains such as blood at lower washing machine temperatures. This means they save energy and are gentler on clothes. Some people are allergic to biological washing powders but this may be overcome by encapsulating the enzymes in wax from which they are only released during the wash. Another wide spread use of enzymes is that of pectinases in food modification. Pectin is a substance which, is found in cell walls and helps to hold the structure together. Pectinase is the name given to a group of enzymes which, break down pectins. They are therefore used to partially digest fruit and vegetables in baby food and to help extract fruit/vegetable juices. ...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

    How does the concentration of enzymes affect the breakdown of starch by a-amylase in ...

    4 star(s)

    The base of the plates appeared to be curving upwards slightly. This causes a slight complication in the measurement of the depth of the agar that fills the plates, as due to the curved surface, the plate will not be filled at an even 6mm depth.

  2. The effect of Electromagnetic Fields on Enzyme Activity

    Therefore in a cell any positive ions will be probably attracted to the negative pole of the field and the negative ions to the positive side. The causes of this would probably be determined by how strong the induced electric field is and how powerful the electromagnetic field itself is.

  1. Investigation into Pectinase

    If time allowed it I would test on a wider range of PH's and treble check them etc. So I will complete my experiment as follows considering I have restrictions on the amount of time I have and the amount of apparatus and the accuracy of it: I will stir

  2. Investigating Factors Affecting Enzyme Activity.

    An increase in the concentrations of the substrate or the enzyme will expectedly be in direct proportion to the rate of reaction in a positive sense, i.e. the higher the concentration, the higher the rate that the products of reacting hydrogen peroxide with catalase will be.

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