What is the length of one loop of BDNA?
Correct answer: A. 3.4 nm
- A. 3.4 nm
- B. 0.34 nm
- C. 20 nm
- D. 10 nm
Explanation
B-DNA is an antiparallel double helix. The double-strand or duplex is coiled plectonemically in a right-handed fashion around a common axis, like a rope staircase twisted in a spiral. The coiling produces alternate major and minor grooves. One turn of the spiral has a distance of 3.4 Å between two adjacent nucleotides.
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About Chromosomes
Chromosomes are DNA-protein structures that carry genes and become visible during cell division. Coverage includes chromatin, centromeres, sister chromatids, homologous chromosomes, chromosome number, and the distinction between diploid and haploid cells, with links to DNA replication, mitosis and meiosis.
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