DNA is a polynucleotide consisting of repeating monomer units called nucleotides.
Identify the three chemical components that covalently link together to form a single DNA nucleotide monomer.
In B-DNA, the distance along the helical axis increases by 0.34 nm0.34\text{ nm}0.34 nm for every complementary base pair. A diploid somatic cell of a certain mammalian species contains a total of 6.8×1096.8 \times 10^96.8×109 nucleotides in its genomic DNA.
Calculate the total length of the DNA double helix in this mammalian cell. Give your answer in metres, rounded to 3 significant figures.
Practise AQA GCSE Biology 6.1 Reproduction with exam-style questions for Foundation and Higher tier. 60 questions covering 6.1.1 Sexual and asexual reproduction, 6.1.2 Meiosis, 6.1.3 Advantages and disadvantages of sexual and asexual reproduction (biology only), 6.1.4 DNA and the genome, 6.1.5 DNA structure (biology only), 6.1.6a Genetic inheritance, 6.1.7 Inherited disorders, and 6.1.8 Sex determination, matched to the AQA GCSE Biology (8461) specification and written in Paper 1 and Paper 2 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.