(a(i))[2]
Describe what the spindle does during this stage of mitosis.
(a(ii))[2]
Chromosomes contain DNA. Describe the structure of one monomer in a DNA molecule.
(b(i))[2]
Suggest why telomerase activity matters in stem cells.
(b(ii))[1]
Suggest why tumour cells make high concentrations of telomerase.
(b(iii))[3]
Scientists have investigated treating cancer by blocking telomerase action. One approach studied is the insertion of small, single-stranded DNA into cancer cells. These DNA segments have a base sequence complementary to a section of the mRNA transcribed from the gene that codes for telomerase. Explain how inserting small, single-stranded DNA could stop translation of the mRNA so that telomerase is produced.