OCR General Certificate of Secondary Education (GCSE) Biology Practice Exam

Who are credited with the discovery of DNA?

1. Hershey and Chase

2. Lincoln and Lee

3. Watson and Crick

4. Franklin and Wilkins

The correct answer is: Watson and Crick

The discovery of DNA's double helix structure is credited to Watson and Crick, who, in 1953, proposed the model based on x-ray diffraction images taken by Rosalind Franklin and the data gathered by other scientists. Their work provided crucial insights into how DNA carries genetic information and replicates, which has been fundamental in the fields of genetics and molecular biology. Watson and Crick’s model illustrated that the two strands of DNA are intertwined in a helical structure, with bases on the inside, explaining how genetic information is stored and passed on. This discovery laid the groundwork for advancements in genetic research and biotechnology. The other individuals mentioned, while they contributed to the understanding of DNA and genetics, did not result in the identification of the DNA structure itself: - Hershey and Chase are known for their experiments with viruses that confirmed DNA as the genetic material but did not describe its structure. - Lincoln and Lee are not recognized figures in the context of DNA discovery; they seem to be fictional or misidentified names. - Franklin and Wilkins contributed important x-ray images and diffraction patterns that aided Watson and Crick, but they are distinct from the model creation attributed to Watson and Crick.