The Effect of Glucose Concentration on Anaerobic Respiration in Yeast
Aim:To investigate the effect of glucose concentration on anaerobic
respiration in yeast.
Equipment list:
2* conical flask
Delivery tube with bung
Dropper
Yeast
Glucose
Limewater
Water bath
Stopwatch
Measuring Cylinder
Method:I am going to do 5 tests & each test will be performed 3 times
to get an average result. In one conical flask, I will mix together
25ml of yeast & 25ml of a glucose solution, with a delivery tube with
a bung in the top of it and leave it for 5 min so it gets
acclimatised; in the other conical flask I will put enough water to
cover the end of the delivery tube.
On the first test I will use a 10% concentration of glucose.
On the second test I will use a 15% concentration of glucose.
On the third test I will use a 20% concentration of glucose.
On the fourth test I will use a 25% concentration of glucose.
On the fifth test I will use a 30% concentration of glucose.
I will then put the yeast & glucose mixture in a warm water bath and
count how many bubbles of CO2 are produced within 5 min.
Fair Test:to make it a fair test, I am going to keep the water
temperature, volume of yeast and glucose, concentration of yeast and
the timings constant and the one thing I will change is the
concentration of the glucose so we can tell how the concentration of
glucose effects the respiration of yeast.
Prediction: I predict that the conical flask with the yeast and the
most glucose concentration will respire quickest.
[IMAGE]The conical flask with the yeast and the least glucose
concentration will respire slowest. This is because of the Lock and
Key Theory. Enzymes basically work due to the 'lock and key' theory,
where the substrate (the 'key') fits into the active site on the
enzyme and they bind together, the reaction takes place and the
Data from Table 1. confirms the theory that as the concentration of glucose increases so will the absorbance of the solution when examined with the glucose oxidase/horseradish peroxidase assay. Glucose within the context of this assay is determined by the amount of ferricyanide, determined by absornace, which is produced in a one to one ratio.1 Furthermore when examining the glucose standards, a linear calibration curve was able to be produced (shown as Figure 1). Noted the R2 value of the y = 1.808x - 0.0125 trend line is 0.9958, which is statistically considered linear. From this calibration curve the absorbance values of unknowns samples can be compared, and the correlated glucose concentration can then be approximated.
2. A test tube was then filled with 35ml of yeast and placed in the
We then took 1ml of the 10% glucose solution again using the glucose rinsed pipette and added it to test tube 1, we then filled the H2O rinsed pipette with 9ml of H2O and added it to test tube one; making 10ml of 1% solution.
Each subsequent trial will use one gram more. 2.Put baking soda into reaction vessel. 3.Measure 40 mL vinegar. 4.Completely fill 1000 mL graduated cylinder with water.
3.) Divide your 30g of white substance into the 4 test tubes evenly. You should put 7.5g into each test tube along with the water.
These labels indicated the lactose solution that was be placed into the mini-microfuge tubes. The varying lactose ph solutions were obtained. The four miniature pipets were then used, (one per solution,) to add 1mL of the solution to the corresponding mini-microfuge tubes. When this step is completed there were two mini-microfuge tubes that matched the paper towel. Then, once all of the solutions contained their respective lactose solutions, 0.5mL of the lactase enzyme suspension was added to the first mini-microfuge tube labeled LPH4 on the paper towel, and 4 on the microfuge tube. As soon as the lactase enzyme suspension was added to the mini-microfuge tube, the timer was started in stopwatch mode (increasing.) When the timer reached 7 minutes and 30 seconds, the glucose test strip was dipped into the created solution in the mini-microfuge tube for 2 seconds (keep timer going, as the timer is also needed for the glucose strip. Once the two seconds had elapsed, the test strip was immediately removed, and the excess solution was wiped gently on the side of the mini-microfuge tube. The timer was continued for 30 addition seconds. Once the timer reached 7:32 (the extra two seconds accounting for the glucose dip), the test strip was then compared the glucose test strip color chart that is found on the side of the glucose test strip
2. Drop a gummy bear into each of your prepared beaker or cup and place the beaker or cup
Third, grab the left edge of the Kool-Aid packet between your thumb and index finger. With your other hand, begin peeling the upper-left corner until the entire top of the envelope is removed. Next, dump the contents of the envelope into the pitcher. Notice how the powder floats before settling on the bottom of the pitcher. Then, take the measuring cup and scoop two cups of sugar into the pitcher as well. At this point, adding the water is a crucial step. Place the pitcher under the water faucet and slowly turn on the cold water. If the water is turned on too quickly, powder will fly all over when the initial gusts of water hit. After the pitcher is filled within two inches of the top, turn the water off and get prepared to stir. With the wooden spoon submersed three-quarters of the way in the liquid, vigorously stir in a clockwise motion until all of the powder is dissolved.
The Effects of Concentration of Sugar on the Respiration Rate of Yeast Investigating the effect of concentration of sugar on the respiration rate of yeast We did an investigation to find how different concentrations of sugar effect the respiration rate of yeast and which type of concentration works best. Respiration is not breathing in and out; it is the breakdown of glucose to make energy using oxygen. Every living cell in every living organism uses respiration to make energy all the time. Plants respire (as well as photosynthesise) to release energy for growth, active uptake, etc…. They can also respire anaerobically (without oxygen) to produce ethanol and carbon dioxide as by-products.
· First I will fill up the ice cream tub with water at one of the
Dab on a cotton ball and rub it. You may also put a cotton ball soaked as a compress for an immediate cooling effect. Do this two times a day in the evening and when in the morning.
2. In the lab, equal amounts of warm water (⅘ the volume of the test tube) and equal amounts of yeast (2 grams) were placed in three different test tubes. A balloon was placed on each of the test tubes to catch the carbon dioxide that was released. The tubes were observed every two minutes for twenty minutes to check the changes in the balloon diameter and any change within the tubes.
¨ After one minute use forceps to take it out and put it in a test
To make sure it is a fair test; the procedure is repeated a couple of
This lab attempted to find the rate at which Carbon dioxide is produced when five different test solutions: glycine, sucrose, galactose, water, and glucose were separately mixed with a yeast solution to produce fermentation, a process cells undergo. Fermentation is a major way by which a living cell can obtain energy. By measuring the carbon dioxide released by the test solutions, it could be determined which food source allows a living cell to obtain energy. The focus of the research was to determine which test solution would release the Carbon Dioxide by-product the quickest, by the addition of the yeast solution. The best results came from galactose, which produced .170 ml/minute of carbon dioxide. Followed by glucose, this produced .014 ml/minute; finally, sucrose which produced .012ml/minute of Carbon Dioxide. The test solutions water and glycine did not release Carbon Dioxide because they were not a food source for yeast. The results suggest that sugars are very good energy sources for a cell where amino acid, Glycine, is not.