Some bacteria's require a certain amount of light in order to function properly and there fore survive. Escherichia coli is found in the gut and intestines of mammals.
Staphylococcus albus is generally a skin dwelling bacteria
Aim: To test whether the amount and type of light that the bacteria's E.coli and S.albus are subject to causes changes in their growth rates and habits.
To test whether the growth rates and habits of the bacteria's E. coli and S. albus are subject to change when to a varying amount and type of light.
Hypothesis: that the different types of light will affect the growth rate of the bacteria's. From prior knowledge and assumption of the environment, it is believed that higher temperatures will assist in the growth rate in the agar plates. Therefore it is believed that the agar plates placed in full light will produce more bacteria.
Due to the type of light used for the full light part of the experiment there will be higher temperatures and therefore grow better than the no light and day light plates which are at lower temperatures.
Equipment and Materials:
1 6 agar plates
2 E. coli and S. albus bacteria
3 Light
4 Day light
5 Cupboard
6 Dropper
7 Labels
8 Adhesive tape
Method:
1. using three agar plates make a lawn culture with E.coli, do the same with the other three agar plates with S.albus.
2. Separate into the following groups - Daylight i. E.coli (1) ii. S.albus (2) - No light i. E.coli (3) ii. S.albus (4) - Full light i. E.coli (5) ii. S.albus (6)
3. Place all plates in cupboard and incubate for 3 days undisturbed.
4. Place each pair of plates in the appropriate location - Full light in an area that allows it to be in constant effect of the light and undisturbed with the exception of the data recording - No light in an area which allows it to be in almost constant complete darkness and undisturbed with exception of data recording - Day