Which statement best describes cancer cells? They grow as a single layer of cells.
They cease to reproduce after 20–50 mitotic divisions.
They reproduce only when needed to replace missing cells.
They are not regulated by contact inhibition.

They are not regulated by contact inhibition.

Explanation:

Contact inhibition is a form of controlling cells. Cancer doesn't have contact inhibition, which is one of the reasons why it spirals out of place so easily.

enzyme speed up the reactions

try using substitution:

x + y - 6 = x - y. (i'm not giving you the exact answer). since 0 = x - y, then sub 0 in the equation with x - y. combine your like terms, and then use inverse operations, and you'll have your answer.

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