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

Rate of respiration in Yeast.

Extracts from this document...

Introduction

Aim: I am going to investigate the rate of respiration of yeast cells in the presence of two different sugar solutions: glucose, sucrose. I will examine the two solutions seeing which one makes the yeast respire faster. I will be able to tell which sugar solution is faster at making the yeast respire by counting the number of bubbles passed through 20cm of water after the yeast and glucose solutions have been mixed. Prediction: I predict that the glucose solution will provide the yeast with a better medium by which it will produce a faster rate of respiration. This is because glucose is the simplest type of carbohydrate (monosaccharide). However sucrose is a complex sugar it contains large molecules making it a disaccharide. Due to the large molecules being saturated and the small molecules being unsaturated this will allow the glucose to mix easily with the yeast therefore making it respire more frequently. The sucrose sugar however having larger molecules will find it harder to mix in with the yeast; this will make the rate of respiration in the sucrose much slower as it is not as efficient as the glucose. ...read more.

Middle

In another test tube I will place 15 cm of water. Into this test tube I will place the other end of the delivery tube. I will start the stopwatch and begin counting the number of bubbles that come through into the water. If no bubbles appear then I will gently shake the test tube full of yeast and sugar this may allow any blockages in the delivery tube to clear and we will be able to see if any bubbles form in the water. After two minutes are over I will record the number of bubbles that appeared and record on a sheet of paper. I will dispose of the contents of the test tubes and replace them with new ones. I will repeat the test for both the glucose and sucrose five times in the same manner. Method: After collecting all of my equipment and setting it up. I measured out 3cm of yeast and placed it inside a test tube. To this I added 5cm of glucose solution. I allowed it to heat inside a beaker full of warm water which was at 45 degrees Celsius. After leaving the test tube in there for 1 minute I collected another test tube and inside it I placed 15cm of water. ...read more.

Conclusion

I received no anomalous results. We should have had another sugar to use as we could have compared it to the glucose and sucrose and this would have provided us with better results. I think that there was enough evidence to draw a conclusion however if we had used another type of sugar it would have made the evidence much more precise and clearer. I don't think that my method could have been improved in any way unless another sugar was utilized. There were some things that were difficult to keep constant in the experiment and this is where my results may have wavered slightly. It was difficult to keep the temperature of the warm water constant as it dipped at times which could have had an effect on how efficient the enzymes were. The delivery tubes were becoming blocked sometimes and by shaking the test tube it cleared them. However as we shook the test tube a large number of bubbles were formed which may not have formed if we didn't shake the test tube. Also we might have been shaking the test tubes at different speed which may have caused a greater number of bubbles to be released. Overall I felt that the experiment was accurate and reliable and there was not much that could have been changed on it. By Omar Jamshad 10S ...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

    What is Type 1 diabetes

    3 star(s)

    Diabetic acidosis, a life-threatening condition caused by the lack of insulin. Late-stage diabetic complications Retinopathy, which can cause blindness. Diabetic neuropathy, which can cause foot ulcers and foot infections. Diabetic kidney disease, which can lead to kidney failure. Atherosclerosis, particularly in smokers and those with high blood pressure.

  2. Peer reviewed

    "An investigation into the Respiration of Carbohydrate Substrates by Yeast."

    5 star(s)

    25cm3 of baker's yeast and 25 cm3 of sucrose was mixed together and preheated at the required temperature for 15 minutes in an electronic water-bath. 2. 400cm3 of water was preheated to the same temperature as the yeast using the Bunsen burner.

  1. Peer reviewed

    Effect of Caffeine on the Heart Rate of Daphnia

    3 star(s)

    nervous system - due to the translucent exoskeleton, and the visibly altered heart rate. They are tolerant of being observed live under a cover slip and appear to suffer no harm when returned to open water. In this experiment, it is intended to study the effect of different concentration of caffeine solutions on the heart rate of Daphnia.

  2. Rate of Respiration

    as much glucose available to the yeast than just using glucose or fructose therefore there will be more glucose molecules in the same volume, so more sugars are available for respiration. Because of this it will produce a lot more CO2 in the same amount of time.

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

    these are then used to produce ATP. Yeast (zymase complex) Glucose + Oxygen Water + Carbon Dioxide + Energy C6H12O6 6O2 6H20 6CO2 2880 Kj/mole In Anaerobic When oxygen is not present, hydrogen cannot be disposed of by forming H2O.

  2. An investigation to see whether the concentration of Sucrose effects the amount of Carbon ...

    We found this because we massed the separate solutions at regular intervals and noticed that the greatest mass loss was from the sucrose solution and we took the loss in mass to be the mass of carbon dioxide (gas).

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

    (Especially oil) - Glucose and saline solution are safe, for safety reasons; prevent drinking since the apparatuses are sometimes contaminated. - The heater can be very hot, prevent touching it after the testing - Make sure that the power supply connected to the heater is off before taken out of

  2. Effect of Caffeine on the Heart Rate of Daphnia

    Hypothesis: The higher the concentration of caffeine solution, the higher the heart rate of Daphnia. 3.1 Apparatus: * Cavity slides * Dropping pipettes * Muslin cloth * Petri dish * Spatula * Stopwatch * Paper towels * Light microscope 3.2 Materials: * Culture of Daphnia (water fleas)

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