Final answer:
The Watson and Crick model revealed DNA's structure as a double helix with antiparallel strands and specific base pairing: A with T, and C with G. It was grounded in prior findings, such as Chargaff's rules and Franklin's X-ray crystallography data, and elucidated the transmission of genetic information, paving the way for further discoveries in molecular biology.
Step-by-step explanation:
The Watson and Crick model of DNA is a seminal concept in biology that explains the double helical structure of DNA. According to this model, DNA is composed of two antiparallel nucleic acid chains, with the 5' end of one chain adjacent to the 3' end of the other. The two strands form a right-handed helix, with the sugar and phosphate groups creating the backbone of the structure and the nitrogenous bases positioned on the inside. The bases pair in a specific manner: adenine (A) with thymine (T), and cytosine (C) with guanine (G), ensuring a consistent width throughout the helix.
The insights provided by Watson and Crick's model were built upon existing research. Chargaff's experiments had shown that the amounts of A and T, and of C and G, were roughly equal in any given DNA molecule, crucial for the concept of base pairing. Moreover, Rosalind Franklin's X-ray crystallography provided the necessary structural details that led to the double helical model. The Hershey-Chase experiments had confirmed that DNA is the genetic material, which the Watson and Crick structure further explained, showing how it could carry and transmit genetic information due to the sequence of bases along the DNA strands.
This model also paved the way for understanding the mechanisms of cell division, genetic inheritance, and protein synthesis. By illustrating how complementary base pairing is crucial for DNA replication and function, the Watson and Crick model has become a cornerstone of molecular biology.