Answer:
a. contact with other cells
Explanation:
Contact inhibition prevents cells from further growth. When a sungular cell is in contant with another, it will stop it's growth right away.
In cell biology, contact inhibition as to do with two distinct but close phenomena: contact inhibition of locomotion (CIL) and contact inhibition of proliferation (CIP).
CIL is regarded as the avoidance attributes shown by fibroblast-like cells when in contact with each other resulting in changes of their movement in a separate direction to prevent future collision. In times when such collision is unpredictable, a separate biological process is observed resulting the cells growth to come to an end in a cell-density reliat way.
Contact inhibition leads to regulation of normal tissue growth, differentiation, and development.
It is essential to recall that both forms of regulation are usually silenced and inhibited in times of organogenesis in the course of embryonic development and tissue and wound healing. Also, contact inhibition of locomotion and proliferation are silenced in cancer cells prompting tumorigenesis.
