Investigation to find the lowest temperature that kills all the yeast cells in suspension of fresh bakers yeast
Investigation to find the lowest temperature that kills all the yeast cells in suspension of fresh bakers yeast
Yeast has the ability to convert sugar to alcohol (ethanol) during anaerobic respiration. This process is known as fermentation and is caused by enzymes in yeast.
They are temperature sensitive and as temperature increases, rate of reaction increases. This is due to both the enzyme and substrate having greater kinetic energy, therefore moving faster, having more frequent collisions and meaning that the substrate molecules enter the active site more often. However, above a certain temperature, the enzymes molecule becomes denatured. This is due to the enzymes vibrating so energetically that bonds holding the molecule together begin to break and the enzymes molecule starts to lose it shape and activity.
The enzyme does not denature as temperature decreases but takes place slower and slower. (Bibliography (1))
The following investigation is going to be to try and find the lowest temperature at which all the yeast cells die.
Equipment
Boiling tube (x11) - needed to hold the substrates for reaction
Thermostatic water bath- This maintains a constant temperature for the substrates to react in.
Stopwatch - To conduct a fair test as the test tubs must be subjected to the relevant temperatures for the same amount of time. This allows an accurate reading to 4 significant figures. (200 words)
0 cm3 Pipette and pipette filler (x2)- To ensure accurate measurements of each substrate. Use one for the yeast suspension and one for the sugar solution. Accurate to +/- 0.4cm3, more accurate then a measuring cylinder (+/-1cm3)
Yeast has the ability to convert sugar to alcohol (ethanol) during anaerobic respiration. This process is known as fermentation and is caused by enzymes in yeast.
They are temperature sensitive and as temperature increases, rate of reaction increases. This is due to both the enzyme and substrate having greater kinetic energy, therefore moving faster, having more frequent collisions and meaning that the substrate molecules enter the active site more often. However, above a certain temperature, the enzymes molecule becomes denatured. This is due to the enzymes vibrating so energetically that bonds holding the molecule together begin to break and the enzymes molecule starts to lose it shape and activity.
The enzyme does not denature as temperature decreases but takes place slower and slower. (Bibliography (1))
The following investigation is going to be to try and find the lowest temperature at which all the yeast cells die.
Equipment
Boiling tube (x11) - needed to hold the substrates for reaction
Thermostatic water bath- This maintains a constant temperature for the substrates to react in.
Stopwatch - To conduct a fair test as the test tubs must be subjected to the relevant temperatures for the same amount of time. This allows an accurate reading to 4 significant figures. (200 words)
0 cm3 Pipette and pipette filler (x2)- To ensure accurate measurements of each substrate. Use one for the yeast suspension and one for the sugar solution. Accurate to +/- 0.4cm3, more accurate then a measuring cylinder (+/-1cm3)
