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

The effect of substrate of yeast fermentation and its respiration rate

Extracts from this document...

Introduction

The effect of substrate of yeast fermentation and its respiration rate. Aim: The aim is to measure the amount of carbon dioxide bubbles produced by three different respiratory substrates; glucose, sucrose and starch that are acted upon by yeast. To determine, which substrate produces the most amount of bubbles. I will carry out this experiment by reacting yeast with the three different respiratory substrates at constant temperature, pH, mass, volume and other variables and I will measure the rate of respiration. I will add each respiratory substrate sugars with yeast and that will produce alcohol, carbon dioxide and energy and I will measure the rate at which most bubbles are produced for each sugar. Yeast + Respiratory Substrate Bubbles (CO2) + Alcohol + Energy Prediction: I predict that when glucose reacts with yeast it will produce most amount of bubbling than sucrose and starch and therefore the rate of respiration of glucose with yeast will be higher than with sucrose and glucose. ...read more.

Middle

Starch is a polysaccharide which consists of many units of glucose linked together by a glycosidic bond. It is a long chain of molecules and branched molecules. * This is a polysaccharide which has many units of glucose linked together. It is a very compact structure therefore hard to breakdown. It is difficult to break down all these glycosidic bonds and the structure is very compact. Therefore starch will have the lowest rate of respiration and will produce least amount of bubbles. Glucose is a simple molecule, a monosaccharide so it is easy to break down and therefore it will have the highest rate of respiration. Alcohol will be produced much quicker and more bubbling will be recorded. Equipment: * Respiratory substrates (glucose, sucrose, starch) * Yeast * Distilled water * Measuring cylinder * 3 Test tubes * 100 cm³ beakers * 100 cm³ syringe * 100 cm³ measuring cylinder * flask * cork stopper with tube * rod to stir * water bath * weighing scale * weighing boat * cork stopper * 250 cm³ flask * gloves * lab coat Method: * Get all the equipment ready. ...read more.

Conclusion

Place the flask in the water bath with set temperature of 37ºC for 10 minutes. Then as the bubbling starts immediately place the cork stopper onto the flask. Measure the volume of gas produced. * Repeat the same procedure for test tubes B and C. * Repeat the same procedure for sucrose and starch. * Take the readings. Fair test: To ensure that the experiment is fair there are certain variables that must be kept constant. Temperature and pH must be constant in order to obtain accurate results. To keep the temperature constant I will use the water bath to maintain the temperature of 37ºC as this is the optimum temperature for the enzymes to work at its best. I will use the buffer solution to monitor the pH value. I will ensure that I use the same measuring cylinder and same volume of yeast and sugars to maintain the accuracy. I will repeat the experiment three times for each sugar to increase the degree of accuracy. Resources: http://www.scientificpsychic.com/fitness/carbohydrates.html http://en.wikipedia.org/wiki/Sucrose http://www.scientificpsychic.com/fitness/carbohydrates1.html Essential AS Biology for OCR, Glenn and Susan Toole, nelson thornes pages; 28, 30. 1 ...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. Peer reviewed

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

    5 star(s)

    that the optimum temperature would be 30-40°C (due to the favourable conditions for enzymes/ denaturation) and the concentration would be high but not the highest (due to the kinetic theory/ osmotic effects). Limitations/ modifications from the pilot. From this experiment we can clearly see the most gas was produced at

  2. Peer reviewed

    Effect of Caffeine on the Heart Rate of Daphnia

    3 star(s)

    However, there is a drop in the heart rate for 0.4% and 0.5% of caffeine solution. This is an anomaly shown in the experiment. Reference to other research papers and the results from other students doing the same experiment as well as consultant to experienced lecturers reveal that the

  1. Rate of Respiration

    Facilitated Diffusion. Facilitated diffusion is the transport of substances across a membrane by a trans-membrane protein molecule. The transport proteins are specific for one molecule (for example a carrier protein for glucose will not diffuse a sucrose molecule). Molecules are transported down a concentration gradient, hence facilitated diffusions a passive diffusion process.

  2. Effect of Caffeine on the Heart Rate of Daphnia

    This shows that caffeine also exhibits antibacterial properties. Anatomy of Daphnia 1.2 Problem statement: How does the concentration of caffeine solution affect the heart rate of Daphnia? 1.3 Aim: To determine the effect of concentration of caffeine solution on the heart rate of Daphnia.

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

    This is a condensation reaction whereby the net result is to remove a molecule of water. The complementary process, whereby complex molecules can be split into their component parts, is called hydrolysis. Fructose is a monosaccharide that forms a five-sided ring.

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

    are hydrogen bonds which make the shape of the alpha-helix or beta-pleated sheet coil and fold. The hydrogen bonds occur between the oxygen in the -CO group of one amino acid and the hydrogen in the -NH group of another amino acid.

  1. Investigating Respiration in Yeast

    The next three pages is a Preliminary Investigation, then the main Investigation Results long with the line graph. Preliminary Investigation I am going to measure the rate of CO2 produced by yeast when supplied with three different concentrations of glucose.

  2. Affects of Alcohol on the Body & Fermentation

    These are bottom and top fermentation. Bottom fermentation produces a pale coloured beer, often lighter and contains fewer units of alcohol. These characteristics are developed when yeast is injected at lower temperatures, between 6-8 degrees, and left to mature at zero degrees.

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