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

To Investigate the Effect of Substrate Concentration On Yeast Respiration

Extracts from this document...


TO INVESTIGATE THE EFFECT OF SUBSTRATE CONCENTRATION ON YEAST RESPIRATION This is an experiment to examine how the concentration of the substrate Glucose affects the rate of reaction of the enzyme Yeast. Hypothesis The rate of yeast respiration will increase as the concentration of glucose increases. This is because the active sites of the enzymes in the yeast have fewer substrate molecules to bind with to form an enzyme-substrate complex. Outline Yeast will be suspended in glucose solutions of different concentration in different test tubes. The carbon dioxide produced by respiration of the yeast will be bubbled through the glucose solution and the volume of CO2 produced, used as a measure of the rate of respiration against a given time. A graph will be plotted of the different concentrations against the time taken. ...read more.


Using the cork borer, take a sample of potato, cut this piece in cm intervals using the scalpel and plastic rule. Then cut these a further 2 sections, so there is now 5 sections per 1cm piece of potato. Using distilled water; allow the potato discs to stick to the side of the glass Thistle Funnel. 2. Fill a beaker with about 4cm of the pre-made measured solution of Glucose and using the graduated measuring cylinder, completely fill the 10 cm3 cylinder with the same solution. 3. Immerse the thistle funnel into the beaker with the steam below the surface of the Glucose over the funnel stem. 4. Measure the volume of oxygen evolved in a time of 5mins. 5. Repeat the procedure with the other Glucose solutions. Be aware not to contaminate each solutions with one another, this will cause inaccurate results. ...read more.


When measuring the volumes of water and Glucose, the measurement should be taken from a 90-degree angle to avoid parallax error. Predictions I predict that as the substrate concentration increases, the rate of reaction will go up at a directionally proportional rate until the solution becomes saturated with the substrate Glucose. When this saturation point is reached, then adding extra substrate will make no difference. The rate steadily increases when more substrate is added because more of the active sites of the enzyme are being used which results in more reactions so the amount of Oxygen released in a given time is higher. Once the amount of substrate molecules added exceeds the number of active sites available then the rate of reaction will no longer go up. This is due to the maximum number of reactions being done at once, so any extra substrate molecules have to wait until some of the active sites become available. ...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)

    Repeat step 9 for the other petri dishes. Do not mix up the seedlings (arrange them in small groups on the baking tray, separate from each other). Record the concentration of the lead chloride that each group of seedlings was grown in.

  2. Peer reviewed

    Effect of Caffeine on the Heart Rate of Daphnia

    3 star(s)

    This increase in the number of the adenosine receptors makes the body much more sensitive to adenosine. Consequently, the stimulatory effects of caffeine are substantially reduced, a phenomenon known as a tolerance adaptation, thus the heart rate reduces even though the concentration of caffeine solution increases.

  1. Rate of Respiration

    By cleaning my apparatus I will ensure that there are no substances that may interfere with my experiment (for example there may be a non/competitive inhibitor that may inhibit the enzymes used by yeast to digest the substrates or respiratory enzymes, thus reducing amount of C02 produced)

  2. Investigate one factor that affects the rate of respiration of yeast

    in a table. Obtaining: Volume of gas produced (cm3) in 10 minutes Concentration of glucose solution In 10ml (%) Trial 1 Trial 2 Trial 3 Trial 4 Average Average Rate of Respiration ( cm�/second) 2 20 18 21 19.66667 0.032777778 4 21 19 21 20.33333 0.033888889 6 23 20 22 21.66667 0.036111111 8 23 17 20 23 22 0.036666667

  1. The Effect of Different Substrates on the Rate of Respiration on Yeast (Saccharomyces cerevisiae).

    This meant that more of the substrate was needed and it was found that 30cm3 was enough. * The temperature was important in deciding how quickly the yeast would respire and at 30oC the yeast hardly produced any CO2, at 50oC a better yield was produce but it was found that at 50oC the best yield of CO2 was produced.

  2. Rate of respiration in Yeast.

    I will empty the test tube and replace it with clean water after doing the test with each sugar, so that it doesn't manipulate my results. I will try to enforce these factors in order to keep the test fair.

  1. Investigation on Osmosis using a potato.

    0.10m, 1.15m, 1.20m, and so on. This way would have allowed me to also find out the isotonic point far more accurately then the ones I estimated in the past experiments.. The cutting of the potatoes was the most difficult part of the experiment as although I was recording my

  2. Investigate the effect different concentrations of glucose in a yeast & Glucose solution has ...

    to help this the glassware will be clean to stop any strong alkali's or acid's from affecting the experiment and ruining it. The pH if to high or low can cause the enzymes to denature by breaking the bonds that hold its structure.

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