When glucose is high, cAMP is low; CAP does not bind the lac operator, and RNA polymerase does not bind the lac promoter. CAP is only active when glucose levels are low, which means the cAMP levels are high, and therefore the lac operon can only be transcribed at high rate when glucose is absent. The importance of this is that the bacteria only turns on the lac operon and start using lactose only after they have used up all the preferred energy source which is glucose.
Cancer is an abnormal and uncontrolled multiplication of cells.
<span>Cancer also involves abnormal cell growth with the potential to spread to other parts of the body via blood and to form metastasis. Cancer cells avoid apoptosis (programmed cell death), have the limitless number of cell divisions and promote blood vessel construction. There are more than 100 types of cancers that affect humans with different signs and symptoms and with many different causes. </span>
