Lab 05 Flashcards
What does Ecoli use for nutrients
Glucose and if it has to lactose
What happens when E-coli senses only lactose is present
When e-coli senses only lactose is present the inducer allocatose will de activate the repressor so the lac operon is on. Then RNA polymerase will transcribe the lac Z gene on the lac operon and will produce the enzyme Beta gallactose to split the lactose into glucose.
Why does E-coli prefer glucose
E-coli will prefer glucose to lactose as lactose is a dissacharide and needs to be broken down before consumption.
What does E-coli do when glucose is scarce
When glucose is scarce the secondary messanger cAMP is produced which activates the Cap-binding site. The CAP binding site is right behind where the RNA polymerase starts to transcribe and when it is activated the transcription becomes must more effective.
What was the independent variable
Sugars present
What was the dependent variable
Absorption
What was the control group
Flask with no sugar
What was the treatment groups
Glucose only, lactose only, glucose and lactose
What was the hypothesis
The hypothesis is that when only lactose is present the ONPG will be split, turning yellow
Prediction
If only lactose is present then ONPG will split then turn yellow
Null Hypothesis
The presense of sugars has no effect on absorbancy of E.Coli in a spectrophotometer
Alt hypothesis
The presense of sugars has an effect on the absorbance of E.Coli in a spectrophotometer
Why do we use ONPG in the experiment
We use ONPG in this experiment because B-gal will also split ONPG and so it shows that if ONPG is split lactose is also split. ONPG turns yellow when split
What do we do with the solutions after adding the E-Coli and waiting
We add the solutions to the spectrophotometer to measure abosrbancy
What is an ANOVA test
It is a statistical test to test the null hypothesis, we compare the F-ratio to the F-critical and if the F-Ratio is bigger then we reject the null
