The answer to this is false, a vector is a disease usually spread from a bite.
When lactose is not present, what happens to E. coli is that the genes that produce the enzymes needed to break down lactose are not expressed. The correct answer is B.
Answer:
The membrane is actually semi-permeable.
Explanation:
The membrane being semi-permeable means that, not all the things come in and out of the cell, only if it's really needed. The cell works in a gradient way, and that means that, to balance things, the cell will put in it a substance in a very high concentration outside of it, just to balance things. And this would happen to potassium, the cell would put it inside to balance this gradient, and once all sides have the same amount of potassium, it will stop, and the gradient is finally equal.