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

What is the effect of temperature on the reaction between sucrose and invertase

Extracts from this document...


What is the effect of temperature on the reaction between sucrose and invertase. About enzymes Enzymes are biological catalysts that speed up the rate of reaction without taking part, therefore causing the reaction to use less energy. They are all proteins so having either a primary, secondary or teritary structure ( how it is held together by globular proteins). These structures either build up (anabolism) or break down substances (catabolism). When these enzymes go past their optimum temperature which they work best at they become denatured. This is when the molecule is moving so fast due to very high temperatures that it vibrates so energetically that some of the bonds break causing the enzyme to change shape. At first the substrate just fits less well into the active site but then more bonds break causing the enzyme to loose it's shape more and therefore the more shape that is lost the longer and harder it is for the substrate to bind with the active site. This eventually causes the enzyme to become denatured. About sucrose It is a non-reducing sugar that is formed when C1 of the ? glucose and C2 of the ? fructose join in a condensation reaction. Therefore it is a disaccharide They are join by a 1-2 glycosidic bond. Both carbonyl groups occur within the 1-2 glycosidic bond so there are no free carbonyl groups to reduce the copper in the benedicts solution. Yet both fructose and glucose have a fee carbonyl group therefore can react with benedicts and are reducing sugars. ...read more.


measuring cylinders 1 to measure 5cm( of sucrose 1 to measure 5cm( of invertase - each time * Benedicts 18cm( for each part of experiment * 72 test tubes To hold sucrose and invertase To combine substances To filter into * 18 funnels To filter precipitate from the solution * 3 stirring rods To agitate solution while in water bath * Timer To time how long substances are in the water bath * 3 plastic droppers To measure and transfer sucrose, invertase and benedicts. * Test tube rack To hold test tubes * 90cm( of 2% sucrose It is the substrate we are using for testing * 90cm( of 2% invertase The enzyme being used to break down substrate * Balance To weigh out precipitate Method 1. Collect apparatus 2. Heat water bath to 30?c 3. Measure 5cm( of 2% sucrose into 1 test tube and 5cm( of 2% invertase and 1cm( of benedicts. 4. Put both in water bath for 5 minutes, time using timer. 5. Mix invertase and sucrose together and agitate using stirrer and put back into water bath for 30 seconds for time to react. 6. Add substance to benedicts and put back in the water bath for 5 minutes. 7. Remove from the water bath and filter the solution and leave to dry over night. 8. Repeat this for another 2 times at this temperature 9. Now repeat the whole thing for 40?c, 45?c, 50?c, 55?c and 60?c 10. ...read more.


* Also even though each solution of sucrose and invertase is stirred 4 times it is still a limitation as the rate and pressure can not be determined with the available resources. This may cause the rate of reaction to increase in some experiments as the molecules are agitated and therefore collide more often and therefore form more precipitate. Analysis As the results show that an increasing amount of precipitate is formed as does the temperature. This is due to the fact that the higher the temperature the faster the molecules move therefore the substrate (sucrose) collides with the active site of the enzyme (invertase) more often. This substrate binds with the active site then the invertase breaks down the sucrose into ? glucose and ? fructose. As they both are reducing sugars and can react with the benedicts due to the free carbonyl group the precipitate is formed. Therefore the higher the temperature the more precipitate formed as more frequent collisions are happening. However once the enzyme reaches its' optimum temperature, shown in the results as 55?c, the molecules start to vibrate so energetically that the bonds begin to break causing the shape of the active site to slowly change. The substrate is unable to bind with the active site as effectively causing the amount of precipitate to decrease and eventually become non-existent. The reasons that the precipitate produced increases as the temperature is due to the above as the molecules are starting to collide more often. ?? ?? ?? ?? Jodie Arlott 29/04/05 Biology Course Work ...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 Exchange, Transport & Reproduction 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 Exchange, Transport & Reproduction essays

  1. Marked by a teacher

    Biology coursework planning - the effect of lead chloride on the growth of cress ...

    5 star(s)

    They also fit well in the petri dish. The arrangement of the seeds on the cotton pad will be in a grid form where one seed will be placed on each corner of the squares making up the grid. This will provide enough distance between each cress seed so that

  2. Peer reviewed

    Effect of Caffeine on the Heart Rate of Daphnia

    3 star(s)

    In the Journal of Biological Education (1997) 31, pp. 253-255 by Foster, a method of using a stroboscope to freeze the motion is suggested. The use of stroboscope may overcome the problems of counting faster heart rates. When the frequency of the stroboscope is in phase with the heart beat, it looks as if the motion of heart is freezed.

  1. To find out the factors affecting the refractive index of liquid by using different ...

    to help it stand inside the solution. The ruler represents the normal line of the refraction. Then adjust the ruler towards or away from the light source until the light beam shone on the ruler at the surface of the solution. Since this vertical ruler is perpendicular to the horizontal ruler at the bottom.

  2. Design an experiment to investigate the effect of temperature on the movement of a ...

    tubes in it, to ensure that it has heated up to the correct temperature. Also when I put the beetroot into each of my test tubes I will use a thermometer to check that they have heated up to the right temperature.

  1. The sensitivity of the Benedict's Test-Investigation

    8) Remove and return to the rack. 9) Make a subjective comparison of the colours in each tube by observation. You can use a scale of '+' to '+++++' to record the depth of colour, from lightest to darkest. 10) Use the colorimeter to measure the percentage transmission of each of your samples.

  2. Determine which of the three sugars tested (Glucose, Fructose and Sucrose) is a reducing ...

    PREDICTION: The glucose and fructose (monosaccharides) are reducing sugars and will react with Benedict's solution and form insoluble copper (II) oxide (Colour Change: Blue to a Red-brown precipitate). The sucrose (disaccharides) is a non-reducing sugar and will not react with the Benedict's solution and therefore no colour change will take place.

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