Chapter 12, Problem 10STP

Summary Introduction

To explain:

An example of a technological development that contributed to scientists’ understanding of the structure of DNA.

Introduction:

There were many experiments conducted by scientists such as Griffith, Avery, Hershey and Chase, Chargaff and Watson and Crick that led to the discovery of DNA as the genetic material. Many technological developments such as radioactive labeling and X ray diffraction also contributed to the scientists’ understanding of the structure of DNA.

Answer to Problem 10STP

One important technique was X ray diffraction used by Wilkins and Franklin to study the structure of DNA.

Explanation of Solution

Wilkins worked with X ray diffraction at King’s college in London, a technique that involved aiming X rays at DNA molecule. In 1951 when Franklin joined King’s college, she used X-ray diffraction technique on the famous Photo 51 and collected data. This data was used by Watson and Crick to solve the structure of DNA. The data indicated that DNA was a double helix formed by two strands of nucleotides twisted around each other.

Using franklin’s data, Watson and Crick measured the width of the helix and the spacing of the bases. Together they built a model of the double helix that conformed to other scientists’ research.