1. A normal cell in a laboratory forms a single layer on a dish. When the cell touches other cells, it halts dividing. Which of the following hypotheses explains this phenomenon? a. It was regulated by kinases and cyclins.

b. Cells grow and divide in response to one growth factor.

c. It happens when internal and external signals stimulate genes that help produce self-destructive enzymes.

d. Receptors on adjacent cells have bound to each other causing the cells’ cytoskeleton to form structures that may hinder the signals that activate the growth.

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if, i suppose that a bee stings me swinging my hand away from a bee. then that if, i persist patient when a bee or wasp areas on your surface to investigate a scent or to take h2o and i secreting heavily, the bug ultimately will move of its personal agreement. if i don't need to set for it to disappear, lightly and gently wipe it off with a part of the paper.

other quantities, called derived quantities, are defined in terms of the seven base quantities via a system of quantity equations. the si derived unitsfor these derived quantities are obtained from these equations and the seven si base units.