The basic laboratory observations that lead to the elements every 0.34 nm and every 3.4 nm along the axis formulation of a structure for DNA did not involve of the molecule. biologists. Rather Irwin Chargaff, an analytical, organic chemist, and physicists, Rosalind Franklin and Maurice Wilkins made the laboratory observations that led to Rosalind Franklin Maurice Wilkins the solution of the structure of DNA. Chargaff determined that there were 4 different These astute observations allowed to synthesize nitrogen bases found in DNA molecules; the purines, together a 3-dimentional structure of a DNA molecule adenine (A) and guanine G), and the pyrimidines, with all of these essential features. This structure was cytosine (C) and thymine (T), and he purified DNA from published in 1953, and immediately generated much a number of different sources so he could examine the excitement, culminating in a Nobel Prize in Physiology quantitative relationships of A, T, G, and C. He and Medicine, in 1962 awarded to Franklin, Wilkins, that in all DNA molecules, the mole-percentage Watson, and Crick. of A was nearly equal to the mole-percentage of T, while the mole-percentage of G was nearly equal to the mole-percentage of C. Alternatively, you could state The key elements of this structure are: this as the mole-percentage of pyri-midine bases Double helical structure each helix is made from equaled the mole-percentage of purine bases. These – the alternating deoxyribose sugar and phosphate observations became known as . groups derived from deoxynuclotides, which are the monomeric units that are used to make up polymeric nucleic acid molecules. Each nucleotide in each chain consists of a nitrogen base of either the purine type Rosalind Franklin a x-ray crystallographer (adenine or guanine) or the pyrimidine type (cytosine working in the laboratory of Maurice Wilkins at or thymidine) attached to the 1’-position of Cambridge University used a technique known as to sugar, and a phosphate group, esterified generate images of DNA molecules that showed that DNA had a helical structure with repeating structural
The basic laboratory observations that lead to the formulation of a structure for DNA did not involve biologists. Rather Irwin Chargaff, an analytical, organic chemist, and physicists, Rosalind Franklin and Maurice Wilkins made the laboratory observations that led to the solution of the structure of DNA. Chargaff determined that there were 4 different nitrogen bases found in DNA molecules; the purines, adenine (A) and guanine G), and the pyrimidines, cytosine (C) and thymine (T), and he purified DNA from a number of different sources so he could examine the quantitative relationships of A, T, G, and C. He that in all DNA molecules, the mole-percentage of A was nearly equal to the mole-percentage of T, while the mole-percentage of G was nearly equal to the mole-percentage of C. Alternatively, you could state this as the mole-percentage of pyri-midine bases equaled the mole-percentage of purine bases. These observations became known as . Rosalind Franklin a x-ray crystallographer working in the laboratory of Maurice Wilkins at Cambridge University used a technique known as to generate images of DNA molecules that showed that DNA had a helical structure with repeating structural elements every 0.34 nm and every 3.4 nm along the axis of the molecule. Rosalind Franklin Maurice Wilkins These astute observations allowed to synthesize together a 3-dimentional structure of a DNA molecule with all of these essential features. This structure was published in 1953, and immediately generated much excitement, culminating in a Nobel Prize in Physiology and Medicine, in 1962 awarded to Franklin, Wilkins, Watson, and Crick. The key elements of this structure are: Double helical structure – each helix is made from the alternating deoxyribose sugar and phosphate groups derived from deoxynuclotides, which are the monomeric units that are used to make up polymeric nucleic acid molecules. Each nucleotide in each chain consists of a nitrogen base of either the purine type (adenine or guanine) or the pyrimidine type (cytosine or thymidine) attached to the 1’-position of sugar, and a phosphate group, esterified