Francis Crick and James Watson Quiz

Francis Crick

• Francis Crick won the Nobel Prize in 1962 for his co-discovery of the structure of DNA with James Watson.
• Crick studied physics at University College London and then began graduate work there on the viscosity of water.
• During World War II, he was recruited by the Royal Navy to help develop magnetic and acoustic mines.
• After the war, he decided to retrain in biology and in 1949, he joined the Cavendish Laboratory in Cambridge and began a new PhD on the X-ray diffraction of proteins.
• He met James Watson in 1951, and they began collaborating on the molecular structure of DNA.
• Crick completed his PhD in 1954.
• He moved to California in 1976, where he studied developmental neurobiology and human consciousness.

James Watson

• James Watson won the Nobel Prize in 1962 for his co-discovery of the structure of DNA with Francis Crick.
• Watson enrolled at the University of Chicago at the age of 15.
• He gained a degree in zoology in 1947 and then in 1950 completed his PhD in virus research.
• He moved to the Cavendish Laboratory in Cambridge in 1951 where he began collaborating with Francis Crick.
• After publishing their groundbreaking paper on DNA structure, Watson moved to California briefly before returning to the Cavendish to work with Crick on virus construction.
• He lectured at Harvard and became a professor of biology in 1960.
• He led the Human Genome Project, an international program that aimed to identify and map all the genes of a human chromosome, in 1989.

DNA Discovery

• Crick and Watson's discovery that DNA is composed of a double helix structure proved to be one of the greatest scientific discoveries of the 20th century.
• DNA (deoxyribonucleic acid) is the chemical substance within cells that determines hereditary patterns in all living things.
• Working out its structure helped scientists learn how it can replicate and pass on genetic information and provided crucial insight into how genes work.
• Crick and Watson discovered the structure of DNA after only 18 months of research.
• They built their final DNA model in 3 days and published their groundbreaking work in a paper just one page long.

The Race for DNA

• A global race to discover the structure of DNA had already begun when Crick and Watson met in 1951.
• In 1944, US immunologist Oswald Avery had discovered that DNA carries genetic information, but without knowing DNA's structure, the study of heredity could not advance.
• Key players in the race were US chemist Linus Pauling, and Rosalind Franklin and Maurice Wilkins at King's College London.
• Scientists knew that DNA could pass on genetic information and make copies of itself.
• They knew that the molecule was made up of various components: a "backbone" composed of phosphoric acid and sugar, and four chemical "bases" called adenine (A), thymine (T), guanine (G), and cytosine (C).
• It was unclear how these components fit together or how the molecule could replicate.

Rosalind Franklin & Photograph 51

• Rosalind Franklin was an expert X-ray crystallographer who produced a clear image of DNA - Photograph 51 - showing its double helix structure.
• Franklin was working alongside Maurice Wilkins, but their relationship was hostile, and Wilkins showed Photograph 51 to Crick and Watson without her knowledge.
• Franklin's image helped Crick and Watson confirm the double helix and complete their model.

The Double Helix Model

• The double helix structure of DNA resembles a twisted ladder.
• The phosphoric acid and sugar strands act as the ladder's uprights.
• The paired bases form the rungs.
• Watson and Crick realized that each rung of the ladder must be composed of two bases (either A and T or C and G) bonded together.
• The order of the bases forms the code for genetic information.
• They deduced that when the ladder splits in half, often described as the molecule "unzipping," each "half ladder" bonds with newly formed DNA components to form two new genetically identical double helixes.

Sydney Brenner

• Sydney Brenner was one of the first to see Watson and Crick's DNA model.
• He produced leading research into developmental genetics and molecular biology.
• In 1961, he discovered the encoding process for the amino acids of a protein with Crick.
• Brenner is best known for his work on organ development and cell apoptosis (programmed cell death) through his study of transparent nematodes, for which he jointly received a Nobel Prize in 2002.

Impact of the Discovery

• Discovering the famous double helix structure of DNA enabled the launch of new scientific techniques, such as gene sequencing and genetic engineering.
• It also opened up vast areas of research into inherited medical conditions.

Francis Crick

• Crick and Watson made one of the most significant breakthroughs in scientific history when they determined DNA's double helix structure.
• Crick studied physics at University College London and then worked on the viscosity of water.
• He worked for the Royal Navy during World War II, later retraining in biology.
• Crick joined the Cavendish Laboratory in Cambridge in 1949, where he met Watson and started researching DNA.
• He completed his PhD in 1954 and continued his work on the genetic code.
• He moved to California in 1976, researching developmental neurobiology and human consciousness.

James Watson

• Watson's work in virus research at the University of Chicago led to his groundbreaking study of DNA.
• He studied zoology at the University of Chicago, gaining a PhD in virus research in 1950.
• Watson joined the Cavendish Laboratory in Cambridge in 1951, forming a partnership with Crick that ultimately led to the discovery of DNA's structure.
• He lectured at Harvard and became professor of biology in 1960.
• Watson led the Human Genome Project, an international scientific project aimed at identifying and mapping all human genes, in 1989.

The Race to Discover DNA

• The discovery of DNA's structure was a global race among scientists.
• Avery determined that DNA carries genetic information in 1944, but its structure remained unknown at the time.
• Linus Pauling, Rosalind Franklin, and Maurice Wilkins were among the prominent players in the race to uncover DNA's structure in the 1950s.
• Scientists recognized DNA's ability to pass on genetic information and replicate itself, knowing that the molecule consisted of a backbone of phosphoric acid and sugar, as well as four bases: adenine, thymine, guanine, and cytosine.
• The exact arrangement and function of these components remained a mystery.

Crick & Watson's Approach

• Crick and Watson focused on the investigation with unwavering determination.
• They used evidence from other scientists and combined their knowledge of viral genetics, physics, and X-ray crystallography.
• They built 3D models to replicate DNA's structure based on its chemical properties, after two unsuccessful attempts, they were able to create a successful model.

Franklin's Contribution

• Rosalind Franklin, an expert in X-ray crystallography, captured a clear image of DNA's double helix structure, known as Photograph 51.
• Despite working alongside Maurice Wilkins, their relationship was strained, and Wilkins showed Photograph 51 to Watson and Crick without her knowledge.
• The image was useful for confirming the double helix model, and the final structure was completed by Watson and Crick.

The Double Helix

• DNA's double helix structure resembles a twisted ladder, with phosphate and sugar strands forming the uprights and paired bases forming the rungs.
• The pairing of bases is significant, with adenine always bonding with thymine and guanine with cytosine.
• It is this sequence of bases that forms the genetic code.
• When the DNA molecule "unzips," each half bonds with newly formed components, creating two identical double helixes.

The DNA Discovery's Impact and Recognition

• Watson and Crick completed their model in March 1953, and their discovery was published in a groundbreaking paper in April.
• Franklin's contribution to their work was only acknowledged briefly.
• This discovery was significant as it provided a crucial understanding of genetics and advanced molecular biology.
• Watson, Crick, and Wilkins received the Nobel Prize in Physiology or Medicine in 1962 for their contributions.

Sydney Brenner

• Brenner was one of the first to see Watson and Crick's DNA model.
• After completing his PhD at Oxford, Brenner researched developmental genetics and molecular biology.
• He and Crick discovered the encoding process for protein amino acids in 1961.
• Brenner is known for his work on organ development and cell apoptosis, receiving the Nobel Prize in 2002.

DNA's Applications

• The discovery of DNA's structure led to new scientific techniques including gene sequencing and genetic engineering.
• The double helix structure opened new avenues for research related to inherited medical conditions.

Test your knowledge about the contributions of Francis Crick and James Watson to the discovery of DNA's structure. This quiz covers their academic backgrounds, key collaborations, and achievements including the Nobel Prize in 1962. Challenge yourself and learn more about these influential scientists.