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

To find out how different sugar concentrations affect the respiration of yeast

Extracts from this document...

Introduction

A2 Biology Coursework Aim To find out how different sugar concentrations affect the respiration of yeast, I shall do this by conducting a simple safe experiment, which will involve the timing of the yeasts respiration, when mixed with different sugar concentration solutions. Introduction Yeast is single celled specie of fungi and is commonly used to make bread. Yeasts are commonly found wherever sugar occurs. It has been used for thousands of years to ferment sugar into ethanol i.e. alcohol. Yeast added to dough ferments the sugar in the dough to produce carbon dioxide. Also yeast is a heterotroph as it needs to consume a ready made supply of carbon. Yeast contains an enzyme called zymase, which will only bind with glucose molecules. During fermentation, it breaks down hydrolyses starch into complex sugars, then simple sugars, and finally ethanol and carbon dioxide. Respiration is a process that takes place in all living cells. Yeast can respire aerobically or anaerobically, however for alcohol to be produced yeast must respire anaerobically. Respiration converts sugars taken in by the organism into energy. It is the controlled breakdown of carbohydrates to make energy. The normal form of energy for most living organisms is adenosine triphosphate (ATP), the other products of respiration are carbon dioxide and water. The reaction taking place in aerobic respiration is: C6H12O6 + 6O2� 6CO2 + 6H2O + ATP (ATP) ...read more.

Middle

A catalyst is a substance that speeds up a chemical reaction without being used up in the reaction itself. In a chemical reaction a certain amount of energy needs to be supplied in order for the reaction to take place this called the activation energy, enzymes lower the activation energy required for the reaction to take place. Prediction I predict that as I increase the concentration of glucose the rate of reaction will increase therefore the fermentation of yeast will increase. This is because the glucose acts as the substrate concentration which is binding to the enzyme zymase which is in the yeast. There will be a increase in the speed of the reaction as the glucose (substrate) is added this is because substrate concentration affects the rate of reaction up to a certain point. The higher the substrate concentration the faster the reaction but only to a certain point as there will be too many substrate molecules and there will be no difference. Also I predict that glucose and fructose will have the fastest rate of reaction upon the fermentation of the yeast this is because glucose and fructose are both monosaccharide's and the others have more than one sugar molecule therefore they will take longer because they have to undergo hydrolysis and then start there reaction also the higher the temperature the faster the rate of reaction, this is due to the kinetic energy as the enzymes are more likely to collide with the substrate and fill the active site. ...read more.

Conclusion

8) Using the rubber tubing allow it to run from the top of the rubber bung down into the large bowl of water and through a tight gap of the burette. 9) Start the stopwatch as soon as you add the rubber bung and both mixtures are getting mixed. 10) Record how long it takes until no more Carbon Dioxide is released and the level of water stops and doesn't get reduced any more. 11) For each different sugar Concentration follow out Steps 1 - 10. Variables * Concentration of Solution - this must be kept the same as altering this will increase or decrease the rate of reaction and therefore won't give an accurate reading. * The temperature must be kept the same at all times as altering this means there will be more or less kinetic energy which means the rate of reaction can be affected. * Also there must be the same amount of yeast used in each individual boiling tube as more yeast will slow the reaction down and will respire more slowly. * Change of pH may result in a change in the bonds of the enzyme. The active site will be disrupted and the enzyme will be denatured. * Also when you shake the boiling tube u might shake it more for one and less for the other therefore it will interfere how fast the rate of reaction will occur. By Mohammed Nabeel ...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 Energy, Respiration & the Environment 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 Energy, Respiration & the Environment essays

  1. Marked by a teacher

    Effect of Anaerobic Respiration On Yeast

    5 star(s)

    This will cause more collisions to occur and allow the enzymes to react ore easily and regularly. At 40�C or 50�C I predict that the most will occur at these temperatures. Not all the heat energy will be passed onto the yeast.

  2. Marked by a teacher

    effect of temperature on the rate of respiration in yeast

    5 star(s)

    The equation to an aerobic respiration: C6H12O6 2C3H6O3 + 2 ATP. The chemical energy in glucose can be used to provide the energy required for growth, repair and movement. In fact most things you do require energy. Respiration is a transfer of potential chemical energy to ATP.

  1. Marked by a teacher

    An investigation into the effect of different sugars on respiration in yeast.

    5 star(s)

    When this happens, the enzyme is described as saturated with substrate. Saccharide Enzyme Glucose Glucokinase Fructose Fructanase Sucrose Invertase Maltose Amyloglucosidase and maltase Lactose Lactase Galactose Galactokinase The Collision Theory "For a reaction to occur, particles have to collide with each other.

  2. Marked by a teacher

    Effect of nitrate concentration on the growth of Duckweeds

    5 star(s)

    This will affects the results obtained because a thicker rootlet meant that there was a bigger surface area for the root to absorb more water and uptake more nutrients, this therefore means that more nitrates are taken up and so increased growth.

  1. Marked by a teacher

    Fighter Pilot A Statistical Analysis of Reaction time and its Correlation with Dominant ...

    5 star(s)

    0.229 0.262 0.251 0.304 0.254 0.260 0.344 0.233 0.286 0.222 0.209 0.293 0.248 0.252 0.280 0.218 0.294 0.279 0.276 0.349 0.346 0.267 0.259 0.232 0.245 0.295 0.263 0.257 0.237 0.267 0.293 0.245 0.219 0.326 0.274 0.345 0.278 0.322 0.261 0.245 0.256 0.230 0.289 0.232 0.231 0.308 0.293 0.255 Table 7

  2. Marked by a teacher

    ATP or Adenosine Triphosphate.

    3 star(s)

    organisms able to synthesise complex organic compounds from simple inorganic compounds, use an external source of energy such as light, hence photosynthesise produces ATP. The production is associated with the dependant reaction (thylakoids in the chloroplasts) and consumption or role is in the light independent reaction (in the stroma of the chloroplast).

  1. the effect of bile concentration on the activity of the enzyme lipase during the ...

    Repeat step 5 another three time until you have 80cm3 of 5% bile salts solution in the volumetric flask 7. Using the beaker with distilled water pour the distilled water into the volumetric flask until the solution in the flask reaches the graduation mark 8.

  2. An investigation into the effects of temperature on the rate of anaerobic respiration of ...

    19 23 22 29 29 41 30 16 17 38 21 22 24 26 35 32 45 35 18 20 39 26 22 24 26 36 36 48 40 19 26 40 27 22 25 29 41 37 50 45 22 30 41 27 22 28 31 42 38 51

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