Ncert Exercises & Solutions

The genes causing cancer are called

1. structural genes
2. expressor genes
3. oncogenes
4. regulatory genes

(c) Normal cells have genes called cellular oncogens or proto-oncogenes which are present in inactivated state, but under cortain conditions (like mutation) these get transforrned to cancer causing oncogens, whereas structural gene, expressor gene and regulatory genes are responsible far ragulation of gene expression (operon model).