Question

how are proto - oncogenes and tumor suppressor genes different?
○ proto - oncogenes identify and correct cancer - causing mutations in dna, and tumor suppressor genes attack irregular cell masses using the immune system.
○ proto - oncogenes promote cell division when a cell is ready, and tumor suppressor genes halt cell division when a dna sequence needs correction or repair.
○ proto - oncogenes promote dna repair when errors are detected, and tumor suppressor genes promote dna synthesis when a sequence is error free.
○ proto - oncogenes cause cancer by failing to correct errors of dna synthesis, and tumor suppressor genes cause cancer by promoting unregulated cell division.
○ proto - oncogenes halt cell division when dna contains damage or errors, and tumor suppressor genes promote properly - timed cell division.

Explanation:

Proto - oncogenes are normal genes that promote cell growth and division in a regulated manner when the cell is ready for it. Tumor suppressor genes, on the other hand, act as "brakes" on cell division. They stop cell division when there are issues with the DNA (such as damage or errors) that need to be corrected or repaired before the cell can safely divide again.

• The first option is incorrect because tumor suppressor genes do not attack irregular cell masses using the immune system.
• The third option is wrong as proto - oncogenes do not promote DNA repair (that is more of a role of some tumor suppressor - like functions in some cases, but not proto - oncogenes) and tumor suppressor genes do not promote DNA synthesis.
• The fourth option is incorrect because proto - oncogenes do not cause cancer by failing to correct DNA synthesis errors (they can become oncogenes through mutations and then promote unregulated cell division), and tumor suppressor genes do not cause cancer by promoting unregulated cell division (mutations in them lead to loss of their ability to halt cell division).
• The fifth option is wrong as it has the functions of proto - oncogenes and tumor suppressor genes reversed.

Answer:

Proto - oncogenes promote cell division when a cell is ready, and tumor suppressor genes halt cell division when a DNA sequence needs correction or repair.