English Language · English

Find the proper sequence of the four jumbled sentences (P, Q, R, S) to form a meaningful passage between S1 and S6: S1: Mutations are random changes to the base sequence of genes. S6: Several mutations must occur in the same cell for it to become a tumour cell. P: This is why mutations in them can result in uncontrolled cell division and therefore tumour formation. Q: The few genes that can become cancer-causing after mutating are known as oncogenes. R: Most genes do not cause cancer if they mutate. S: In a normal cell oncogenes are involved in the control of cell cycle and cell division.