NEET BIOLOGY

Detailed explanation-1: -Figure 3: The double-helical structure of DNA. The 3-dimensional double helix structure of DNA, correctly elucidated by James Watson and Francis Crick.

Detailed explanation-2: -Watson and Crick proposed the molecular structure of DNA which they termed the “double helix”. The specific pairing of nucleotides is a key feature of the Watson and Crick model of DNA. Here, each DNA strand is linear and long, comprising smaller units known as nucleotides which in turn form a chain.

Detailed explanation-3: -Answer: Watson and Crick defined DNA as a double helix with two long helical strands twisted together in their paper titled A Structure of Deoxyribose Nucleic Acid. According to them, each DNA strand has discrete units known as bases. The bases along one DNA strand match the bases along the other DNA strand.

Detailed explanation-4: -Created by Rosalind Franklin using a technique called X-ray crystallography, it revealed the helical shape of the DNA molecule. Watson and Crick realized that DNA was made up of two chains of nucleotide pairs that encode the genetic information for all living things.