2017 · Q4
In human body, the cell growth and differentiation are highly controlled and regulated, but in cancer cells
General KnowledgeBiology
- Athere is breakdown of these regulatory mechanisms leading to formation of benign and malignant tumors.
- Bcontrolled cell division and over-production of genetic material occur.
- CRNA is mutated and produced in less amount.
- DDNA is mutated and produced in, less amount.
Explanation
Normal cell growth is held in check by proto-oncogenes, tumour-suppressor genes, and cell-cycle checkpoints. In cancer, mutations break these regulatory mechanisms, producing uncontrolled proliferation that forms benign and malignant tumours. The other options misstate the mechanism: the problem is loss of regulation, not controlled division or reduced RNA/DNA output. Hence A.