You isolate cells from a tumor and study them. you observe that the cells continue dividing, even when dna is damaged, when the cells become crowded, or even when nutrients run low. these observations lead you to suspect that the cells

contain a mutated tumor-suppressor gene.

Explanation:

A tumor suppressor gene performs the function of regulating the proper division of the cells as well as regulating replication.

The tumor suppressor genes perform the following functions :

Maintain the stability of the genome. Regulate cell growth. Regulates cell proliferation rate. Whenever the tumor suppressor genes get mutated it would either result in a loss of its function or a reduction in its function which can lead to the abnormal growth of cells. Hence, if the DNA is damaged, the cells become crowded and the nutrients run low then this indicates that the tumor suppressor genes are mutated.

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