Describe the primary secondary and tertiary structure of DNA

Describe the primary, secondary, and tertiary structure of DNA

Solution

Answer:

1. Primary structure: DNA is made of nucleotides. Nucleotides are arranged in linear fashion by the phosphodiester bonds. Linear structure of DNA is called primary structure.

2. Secondary structure: Helical tructure is called secondary structure. In this structure, two linear polynucleotides are held together by hydrogen bonds and formrs double helical structure. The DNA appears in different helices, hence the DNA is called as A-DNA, B-DNA and Z-DNA.

3. Tertiary structure: It is specific three dimensional shape of DNA that is formed by repeating folding of DNA. This foldings are formed by the histone proteins. Several beads like structures are formed in the tertiary structure called nucleosomes. Hence, the tertiary structure of DNA appears like beads on string.