Final answer:
In B-DNA, there are approximately 10 nucleotides per turn of the helix. This arrangement is a characteristic of the double helical structure of DNA, where the nucleotides are held together by hydrogen bonds and create major and minor grooves.
Step-by-step explanation:
In B-DNA, there are approximately 10 nucleotides per turn of the helix. This arrangement of nucleotides is a characteristic of the double helical structure of DNA. The distance between each turn of the helix is approximately 3.4 nm (formerly 3.6 nm), and within this distance, there are 10 nucleotides stacked inside.
These nucleotides are held together by hydrogen bonds between complementary nitrogenous bases, and the spatial relationship between the two strands creates major and minor grooves where proteins can interact.