Answer:
D.) repressor DNA-binding site mutation
Explanation:
lacl prevents the repressor polypeptide is a mutant that prevent operon from binding lactose, and thus will bind to the operator and be non-inducible.. This mutant will represses the lac operon whether lactose is present or not and the lac operon will not be expressed. It is also called“super-supperesor".
The lacI locus – One type of mutant allele of lacI (callled I-) prevents the production of a repressor polypeptide or produces a polypeptide that will not allow to bind to the operator sequence.
This is also a constitutive expresser of the lac operon because absence of repressor binding permits transcription.
Answer: 1. increase the temperature from 27 degrees Celsius to 37 degrees Celsius
Explanation:
Generally, protease function optimally at temperature range of 55 to 60 degrees Celsius and at lower pH 5.0 to 5.5. Hence increase in temperature to 37 degrees Celsius will increase proteolysis.
The situation that a new technology would be most likely to cause change in existing theory about cell is : D. The technology allows detection of a substance that could not be detected previously
Cell is incredibly small and we still hasn't 100% figured out their perfect mechanism yet. New technology might found the new substance that alter the cell's theory as a whole
hope this helps
Answer:
Cabbage juice
Explanation:
Red cabbage has pH indicator pigment. It changes color when mixed with acid or basic solution.
For acidic solution, the juice turns red.
For neutral, it shows purple color.
For basic solution have pH 8-9 : Blue
pH 10-11: Green
For strong basic solutions: yellow in color.