The Double Helix

The Double Helix: Unraveling the Secrets of Life's Code

The double helix. The very words evoke images of swirling staircases, intricate patterns, and the fundamental building blocks of life. But beyond the visually stunning representations, lies a story of scientific discovery, revolutionary understanding, and ongoing research that continues to shape our world. This comprehensive guide will delve into the fascinating world of the double helix, exploring its structure, function, discovery, and lasting impact on science and medicine. Prepare to embark on a journey into the heart of life itself!

What is the Double Helix?

The double helix is the iconic structure of deoxyribonucleic acid (DNA), the molecule that carries the genetic instructions for all living organisms. Imagine a twisted ladder, where the sides are made of sugar and phosphate molecules, and the rungs are formed by pairs of nitrogenous bases: adenine (A) with thymine (T), and guanine (G) with cytosine (C). This specific pairing, dictated by hydrogen bonds, is crucial to DNA's function and stability. This elegant structure, elegantly spiraling, allows for the efficient storage and replication of vast amounts of genetic information.

The Discovery of the Double Helix: A Scientific Race

The discovery of the double helix is a captivating tale of scientific rivalry and collaboration. While multiple scientists contributed vital pieces of the puzzle, James Watson and Francis Crick are widely credited with the first accurate model in 1953. Their work built upon the X-ray diffraction images produced by Rosalind Franklin and Maurice Wilkins, which hinted at the helical nature of DNA. The intense competition and the ethical considerations surrounding the discovery remain subjects of ongoing discussion, highlighting the complexities of scientific progress. Franklin's crucial contributions are increasingly recognized and celebrated as the science community better understands her role.

The Function of the Double Helix: Replication and Protein Synthesis

The double helix's structure is intrinsically linked to its function. The complementary base pairing allows for precise DNA replication, the process by which a cell makes an identical copy of its DNA before cell division. This ensures the faithful transmission of genetic information from one generation to the next. Furthermore, the sequence of bases along the DNA molecule dictates the order of amino acids in proteins, the workhorses of the cell. This process, known as protein synthesis, involves transcription (DNA to RNA) and translation (RNA to protein), demonstrating the double helix's central role in directing cellular activities.

The Double Helix and Genetic Engineering: Revolutionizing Medicine

Our understanding of the double helix has revolutionized numerous fields, particularly medicine. Genetic engineering, made possible by our ability to manipulate DNA, allows for the creation of genetically modified organisms (GMOs) with enhanced characteristics, from disease resistance in crops to the production of therapeutic proteins. Gene therapy, aimed at correcting genetic defects, holds immense promise for treating inherited diseases. The ongoing research into gene editing technologies, such as CRISPR-Cas9, further underscores the double helix's profound impact on human health.

Beyond the Basics: Variations and Discoveries

While the classic Watson-Crick model provides a foundational understanding, the double helix story isn't static. Different DNA forms exist, including A-DNA and Z-DNA, which possess slightly different helical parameters. Moreover, ongoing research continuously reveals new facets of DNA structure and function, including the intricate interplay between DNA and proteins, the role of epigenetics (changes in gene expression not involving alterations to the DNA sequence itself), and the complexities of the genome’s organization within the cell nucleus.

The Enduring Legacy of the Double Helix

The discovery of the double helix stands as a landmark achievement in science, fundamentally altering our comprehension of life. From understanding heredity to developing revolutionary medical treatments, the double helix's impact is undeniable. As research continues to unravel the intricate details of DNA's structure and function, we can anticipate even more groundbreaking discoveries and applications in the years to come. The double helix is not merely a scientific concept; it's the blueprint of life itself, continually inspiring scientific inquiry and shaping our future.

Conclusion:

The double helix represents a cornerstone of modern biology, a testament to human ingenuity and the power of scientific collaboration. Its discovery marked a turning point in our understanding of life, and its implications continue to shape fields ranging from medicine and agriculture to biotechnology and beyond. The journey of discovery is ongoing, with new insights constantly emerging, ensuring the double helix will remain a central focus of scientific research for generations to come.

FAQs:

1. Can the double helix be seen with the naked eye? No, DNA molecules are far too small to be seen without the aid of powerful microscopes.

2. What are some common misconceptions about the double helix? A common misconception is that the double helix is always perfectly uniform. In reality, its structure can be influenced by various factors, including the surrounding environment and associated proteins.

3. How is the double helix involved in evolution? Mutations in the DNA sequence, altering the base pairings, provide the raw material for evolutionary change. These changes can lead to variations in traits, and natural selection favors those variations that are advantageous.

4. What is the role of telomeres in the double helix? Telomeres are protective caps at the ends of chromosomes, preventing degradation of the DNA during replication. Their shortening is linked to aging and cellular senescence.

5. What are some ethical considerations surrounding DNA technology? Ethical considerations related to DNA technology include issues of genetic privacy, the potential for genetic discrimination, and the responsible use of gene editing technologies.

the double helix: Molecular Biology of the Gene James D. Watson, Tania A. Baker, Stephen P. Bell, 2014 Now completely up-to-date with the latest research advances, the Seventh Edition retains the distinctive character of earlier editions. Twenty-two concise chapters, co-authored by six highly distinguished biologists, provide current, authoritative coverage of an exciting, fast-changing discipline.
the double helix: Unravelling the Double Helix Gareth Williams, 2019-04-18 DNA. The double helix; the blueprint of life; and, during the early 1950s, a baffling enigma that could win a Nobel Prize. Everyone knows that James Watson and Francis Crick discovered the double helix. In fact, they clicked into place the last piece of a huge jigsaw puzzle that other researchers had assembled over decades. Researchers like Maurice Wilkins (the 'Third Man of DNA') and Rosalind Franklin, famously demonised by Watson. Not forgetting the 'lost heroes' who fought to prove that DNA is the stuff of genes, only to be airbrushed out of history. In Unravelling the Double Helix, Professor Gareth Williams sets the record straight. He tells the story of DNA in the round, from its discovery in pus-soaked bandages in 1868 to the aftermath of Watson's best-seller The Double Helix a century later. You don't need to be a scientist to enjoy this book. It's a page-turner that unfolds like a detective story, with suspense, false leads and treachery, and a fabulous cast of noble heroes and back-stabbing villains. But beware: some of the science is dreadful, and the heroes and villains may not be the ones you expect.
the double helix: Genes, Girls and Gamow James D. Watson, 2003 An autobiographical account of Jim Watson's life, following on from The Double Helix, the story of his and Francis Crick's discovery of the structure of DNA (published in 1968). Here is Watson adjusting to new-found fame, carrying out tantalizing experiments and falling in love.
the double helix: The Double Helix and the Law of Evidence David H. Kaye, 2010-05-15 Bridging law, genetics, and statistics, this book is an authoritative history of the long and tortuous process by which DNA science has been integrated into the American legal system. In a history both scientifically sophisticated and comprehensible to the nonspecialist, David Kaye weaves together molecular biology, population genetics, the legal rules of evidence, and theories of statistical reasoning as he describes the struggles between prosecutors and defense counsel over the admissibility of genetic proof of identity. Combining scientific exposition with stories of criminal investigations, scientific and legal hubris, and distortions on all sides, Kaye shows how the adversary system exacerbated divisions among scientists, how lawyers and experts obfuscated some issues and clarified others, how probability and statistics were manipulated and misunderstood, and how the need to convince lay judges influenced the scientific research. Looking to the future, Kaye uses probability theory to clarify legal concepts of relevance and probative value, and describes alternatives to race-based DNA profile frequencies. Essential reading for lawyers, judges, and expert witnesses in DNA cases, The Double Helix and the Law of Evidence is an informative and provocative contribution to the interdisciplinary study of law and science.
the double helix: Molecular Biology of the Cell , 2002
the double helix: The Double Helix James D. Watson, 1969-02 Since its publication in 1968, The Double Helix has given countless readers a rare and exciting look at one highly significant piece of scientific research-Watson and Crick's race to discover the molecular structure of DNA.
the double helix: The Path to the Double Helix Robert Olby, 2013-05-13 Written by a noted historian of science, this in-depth account traces how Watson and Crick achieved one of science's most dramatic feats: their 1953 discovery of the molecular structure of DNA.
the double helix: The 100 Best Nonfiction Books of All Time Robert McCrum, 2018 Beginning in 1611 with the King James Bible and ending in 2014 with Elizabeth Kolbert's 'The Sixth Extinction', this extraordinary voyage through the written treasures of our culture examines universally-acclaimed classics such as Pepys' 'Diaries', Charles Darwin's 'The Origin of Species', Stephen Hawking's 'A Brief History of Time' and a whole host of additional works --
the double helix: The Double Helix James D. Watson, 2011-08-16 The classic personal account of Watson and Crick’s groundbreaking discovery of the structure of DNA, now with an introduction by Sylvia Nasar, author of A Beautiful Mind. By identifying the structure of DNA, the molecule of life, Francis Crick and James Watson revolutionized biochemistry and won themselves a Nobel Prize. At the time, Watson was only twenty-four, a young scientist hungry to make his mark. His uncompromisingly honest account of the heady days of their thrilling sprint against other world-class researchers to solve one of science’s greatest mysteries gives a dazzlingly clear picture of a world of brilliant scientists with great gifts, very human ambitions, and bitter rivalries. With humility unspoiled by false modesty, Watson relates his and Crick’s desperate efforts to beat Linus Pauling to the Holy Grail of life sciences, the identification of the basic building block of life. Never has a scientist been so truthful in capturing in words the flavor of his work.
the double helix: DNA James D. Watson, Andrew Berry, 2004 Along with Frances Crick, James Watson discovered the double-helix structure of the DNA molecule. This book describes the fifty years of explosive scientific achievement that derived from their work, including Dolly the sheep, GM foods & designer babies.
the double helix: Double Helix Eileen Merriman, 2021-08-31 Would you want to know what awaits you? Would you want to be in control of your life . . . and death? What would you do for love? 'Sooner or later, willingly or unwillingly, he’s going to leave you.' The words cut deep. Emily knows Jake is not like his father; he’d never leave her willingly. But if he has inherited his mother's genes, then Huntington’s disease is more than likely to take him away. He may even make the same request his mother made, when Jake was still a teenager: to end the suffering for good.
the double helix: Untangling the Double Helix James C. Wang, 2009 The problem of unraveling two intertwined strands during the duplication of DNA was recognized shortly after the proposal of the DNA double helix structure in 1953. A group of enzymes called DNA topoisomerases solve this problem by breaking and rejoining DNA molecules in a controlled manner, thereby allowing strands to be passed through each other and thus untangledâ€”not just during DNA replication, but also during many other basic cellular processes. Because of their intimate involvement in the workings of the cell, topoisomerases are also the logical targets of many antibiotics (including Cipro) and anticancer agents. This book, written by James Wang, the discoverer of the first topoisomerase and a leader in the field since, presents ten chapters covering the historical backdrop of the DNA entanglement problem and the discovery of the DNA topoisomerases, how DNA topoisomerases perform their magic in DNA replication, transcription, genetic recombination and chromosome condensation, and how they are targets of therapeutic agents. The book should appeal to readers from undergraduates upwards with interests in the biological and clinical aspects of topoisomerase function, or in the mathematics and physics of topology.
the double helix: Double Helix James D. Watson, 1998-02-27 Portions of this book were first published in The Atlantic monthly.
the double helix: In Search of the Double Helix John Gribbin, 1987 Chapters cover such topics as the theories of Darwin, Mendel, and Barbara McClintock, quantum chemistry, and the molecules of life.
the double helix: The Double Helix Structure of DNA R. N. Albright, 2013-12-15 This unique look at the study of DNA goes beyond the science and explores the lives of four great scientists: James Watson, Francis Crick, Maurice Wilkins, and Rosalind Franklin. It was through their complex personal interactions and their devotion to the science that led to breakthroughs surrounding the structure of DNA and our modern understanding of genetics. Readers can learn that science is not about one individual and his or her discoveries, but is the work of many. Numerous scientific breakthroughs can be attributed to competition and rivalry.
the double helix: Double Helix Nancy Werlin, 2009
the double helix: Rosalind Franklin and DNA Anne Sayre, 2000 A biography of one of the four scientists responsible for the discovery of the molecular structure of DNA, the key to heredity in all living things.
the double helix: The Double Helix James Watson, 2012-09-06 The story of the most significant biological breakthrough of the century - the discovery of the structure of DNA. 'It is a strange model and embodies several unusual features. However, since DNA is an unusual substance, we are not hesitant in being bold' By elucidating the structure of DNA, the molecule underlying all life, Francis Crick and James Watson revolutionised biochemistry. At the time, Watson was only 24. His uncompromisingly honest account of those heady days lifts the lid on the real world of great scientists, with their very human faults and foibles, their petty rivalries and driving ambition. Above all, he captures the extraordinary excitement of their desperate efforts to beat their rivals at King's College to the solution to one of the great enigmas of the life sciences.
the double helix: Maurice Wilkins: The Third Man of the Double Helix Maurice Wilkins, 2005-07-14 The Nobel Prize for the discovery of the structure of DNA was given to three scientists - James Watson, Francis Crick, and Maurice Wilkins. It was the experimental work of Wilkins and his colleague Rosalind Franklin that provided the clues to the structure. Here, Wilkins, who died in 2004, gives us his own account of his life, his early work in physics, the tensions and exhilaration of working on DNA, and his much discussed difficult relationship with his colleague Rosalind. This is a highly readable, and often moving account from a highly distinguished scientist who played one of the key roles in the historic discovery of the molecule behind inheritance.
the double helix: DNA James D. Watson, Andrew Berry, Kevin Davies, 2017-08-22 The definitive insider's history of the genetic revolution--significantly updated to reflect the discoveries of the last decade. James D. Watson, the Nobel laureate whose pioneering work helped unlock the mystery of DNA's structure, charts the greatest scientific journey of our time, from the discovery of the double helix to today's controversies to what the future may hold. Updated to include new findings in gene editing, epigenetics, agricultural chemistry, as well as two entirely new chapters on personal genomics and cancer research. This is the most comprehensive and authoritative exploration of DNA's impact--practical, social, and ethical--on our society and our world.
the double helix: Molecular Structure of Nucleic Acids , 1953
the double helix: Avoid Boring People James D. Watson, 2007 Watson looks back on his extraordinary and varied career - from its beginnings as a schoolboy in Chicago's South Side to the day he left Harvard 50 years later, world-renowned as the co-discoverer of DNA - and considers the lessons he has learnt along the way.
the double helix: The Double Helix James Dewey Watson (Biochimiste, Biologiste moléculaire), 1968
the double helix: Life's Greatest Secret Matthew Cobb, 2015-06-11 Life's Greatest Secret is the story of the discovery and cracking of the genetic code. This great scientific breakthrough has had far-reaching consequences for how we understand ourselves and our place in the natural world. The code forms the most striking proof of Darwin's hypothesis that all organisms are related, holds tremendous promise for improving human well-being, and has transformed the way we think about life. Matthew Cobb interweaves science, biography and anecdote in a book that mixes remarkable insights, theoretical dead-ends and ingenious experiments with the pace of a thriller. He describes cooperation and competition among some of the twentieth century's most outstanding and eccentric minds, moves between biology, physics and chemistry, and shows the part played by computing and cybernetics. The story spans the globe, from Cambridge MA to Cambridge UK, New York to Paris, London to Moscow. It is both thrilling science and a fascinating story about how science is done.
the double helix: The Annotated and Illustrated Double Helix James D. Watson, Alexander Gann, 2012-11-06 In his 1968 memoir, The Double Helix (Readers Union, 1969), the brash young scientist James Watson chronicled the drama of the race to identify the structure of DNA, a discovery that would usher in the era of modern molecular biology. After half a century, the implications of the double helix keep rippling outward; the tools of molecular biology have forever transformed the life sciences and medicine. The Annotated and Illustrated Double Helix adds new richness to the account of the momentous events that led the charge.
the double helix: The Double Helix James Dewey Watson, 1968
the double helix: The Man in the Monkeynut Coat Kersten T. Hall, 2014 Tells the story of the English physicist and molecular biologist William T. Astbury and how his work forms a previously untold chapter in the story of the discovery of the structure of DNA.
the double helix: Life at the Speed of Light J. Craig Venter, 2013-10-17 In 2010, scientists led by J. Craig Venter became the first to successfully create 'synthetic life' -- putting humankind at the threshold of the most important and exciting phase of biological research, one that will enable us to actually write the genetic code for designing new species to help us adapt and evolve for long-term survival. The science of synthetic genomics will have a profound impact on human existence, including chemical and energy generation, health, clean water and food production, environmental control, and possibly even our evolution. In Life at the Speed of Light, Venter presents a fascinating and authoritative study of this emerging field from the inside -- detailing its origins, current challenges and controversies, and projected effects on our lives. This scientific frontier provides an opportunity to ponder anew the age-old question 'What is life?' and examine what we really mean by 'playing God'. Life at the Speed of Light is a landmark work, written by a visionary at the dawn of a new era of biological engineering.
the double helix: What Mad Pursuit Francis Crick, 2008-08-06 Candid, provocative, and disarming, this is the widely-praised memoir of the co-discoverer of the double helix of DNA.
the double helix: Double Helix Glen Phelan, 2006 An illustrated introduction to the discovery of DNA for young readers.
the double helix: Spillover David Quammen, 2012-10-04 Read this gripping, timely book about the transmission of deadly viruses from animal to human populations, and how we can fight the current Covid-19 pandemic. WITH A NEW AFTERWORD ON CORONAVIRUS As globalization spreads and as we destroy the ancient ecosystems, we encounter strange and dangerous infections that originate in animals but that can be transmitted to humans. Diseases that were contained are being set free and the results are potentially catastrophic. In a journey that takes him from southern China to the Congo, from Bangladesh to Australia, David Quammen tracks these infections to their source, and asks what we can do to prevent some new pandemic spreading across the face of the earth. As we continue to feel the global impact of Covid-19, discover the book that predicted this viral disaster and the science that could stop the next one in its tracks. 'A tremendous book...this gives you all you need to know and all you should know' Sunday Times 'Chilling... [A] brilliant, devastating book' Daily Mail 'A frightening and fascinating masterpiece of science reporting that reads like a detective story' Walter Isaacson
the double helix: The Double Helix James D. Watson, 2010-11 'It is a strange model and embodies several unusual features. However, since DNA is an unusual substance, we are not hesitant in being bold.' By elucidating the structure of DNA, the molecule underlying all life, Francis Crick and James Watson revolutionised biochemistry.
the double helix: The Double Helix James D. Watson, 1970
the double helix: Rosalind Franklin Brenda Maddox, 2013-02-26 In 1962, Maurice Wilkins, Francis Crick, and James Watson received the Nobel Prize, but it was Rosalind Franklin's data and photographs of DNA that led to their discovery. Brenda Maddox tells a powerful story of a remarkably single-minded, forthright, and tempestuous young woman who, at the age of fifteen, decided she was going to be a scientist, but who was airbrushed out of the greatest scientific discovery of the twentieth century.
the double helix: Francis Crick Matt Ridley, 2012-01-17 Francis Crick—the quiet genius who led a revolution in biology by discovering, quite literally, the secret of life—will be bracketed with Galileo, Darwin, and Einstein as one of the greatest scientists of all time. In his fascinating biography of the scientific pioneer who uncovered the genetic code—the digital cipher at the heart of heredity that distinguishes living from non-living things—acclaimed bestselling science writer Matt Ridley traces Crick's life from middle-class mediocrity in the English Midlands through a lackluster education and six years designing magnetic mines for the Royal Navy to his leap into biology at the age of thirty-one and its astonishing consequences. In the process, Ridley sheds a brilliant light on the man who forever changed our world and how we understand it.
the double helix: Remaking History Jerome De Groot, 2015-07-30 Remaking History considers the ways that historical fictions of all kinds enable a complex engagement with the past. Popular historical texts including films, television and novels, along with cultural phenomena such as superheroes and vampires, broker relationships to ‘history’, while also enabling audiences to understand the ways in which the past is written, structured and ordered. Jerome de Groot uses examples from contemporary popular culture to show the relationship between fiction and history in two key ways. Firstly, the texts pedagogically contribute to the historical imaginary and secondly they allow reflection upon how the past is constructed as ‘history’. In doing so, they provide an accessible and engaging means to critique, conceptualize and reject the processes of historical representation. The book looks at the use of the past in fiction from sources including Mad Men, Downton Abbey and Howard Brenton’s Anne Boleyn, along with the work of directors such as Terence Malick, Quentin Tarantino and Martin Scorsese, to show that fictional representations enable a comprehension of the fundamental strangeness of the past and the ways in which this foreign, exotic other is constructed. Drawing from popular films, novels and TV series of recent years, and engaging with key thinkers from Marx to Derrida, Remaking History is a must for all students interested in the meaning that history has for fiction, and vice versa.
the double helix: The Immortal Life of Henrietta Lacks Rebecca Skloot, 2010-03-01 A NEW YORK TIMES BESTSELLER NOW ADAPTED INTO A HBO FILM STARRING OPRAH WINFREY & ROSE BYRNE No dead woman has done more for the living . . . A fascinating, harrowing, necessary book Hilary Mantel, The Guardian Her name was Henrietta Lacks, but scientists know her as HeLa. Born a poor black tobacco farmer, her cancer cells - taken without her knowledge - became a multimillion-dollar industry and one of the most important tools in medicine. Yet Henrietta's family did not learn of her 'immortality' until more than twenty years after her death, with devastating consequences . . . Rebecca Skloot's fascinating account is the story of the life, and afterlife, of one woman who changed the medical world forever. Balancing the beauty and drama of scientific discovery with dark questions about who owns the stuff our bodies are made of, The Immortal Life of Henrietta Lacks is an extraordinary journey in search of the soul and story of a real woman, whose cells live on today in all four corners of the world. PRAISE FOR THE IMMORTAL LIFE OF HENRIETTA LACKS One of the most graceful and moving non-fiction books I've read in a very long time Dwight Garner, New York Times An extraordinary mix of memoir and science reveals the story of how one woman's cells have saved countless lives Daily Telegraph A heartbreaking account of racism and injustice . . . Moving and magnificent Metro
the double helix: A Crack in Creation Jennifer Doudna, Samuel Sternberg, 2018-06-14 A handful of discoveries have changed the course of human history. This book is about the most recent and potentially the most powerful and dangerous of them all. It is an invention that allows us to rewrite the genetic code that shapes and controls all living beings with astonishing accuracy and ease. Thanks to it, the dreams of genetic manipulation have become a stark reality: the power to cure disease and alleviate suffering, to create new sources of food and energy, as well as to re-design any species, including humans, for our own ends. Jennifer Doudna is the co-inventor of this technology - known as CRISPR - and a scientist of worldwide renown. Writing with fellow researcher Samuel Sternberg, here she provides the definitive account of her discovery, explaining how this wondrous invention works and what it is capable of. She also asks us to consider what our new-found power means: how do we enjoy its unprecedented benefits while avoiding its equally unprecedented dangers? The future of humankind - and of all life on Earth - is at stake. This book is an essential guide to the path that now lies ahead.
the double helix: James Watson and Francis Crick Matt Anniss, 2014-08-01 Watson and Crick are synonymous with DNA, the instructions for life. But how did these scientists figure out something as elusive and complicated as the structure of DNA? Readers will learn about the different backgrounds of these two gifted scientists and what ultimately led them to each other. Their friendship, shared interests, and common obsessions held them together during the frenzied race to unlock the mysteries of DNA in the mid-twentieth century. Along with explanations about how DNA works, the repercussions of the dynamic duo's eventual discovery will especially fascinate young scientists.
the double helix: Concepts of Biology Samantha Fowler, Rebecca Roush, James Wise, 2023-05-12 Black & white print. Concepts of Biology is designed for the typical introductory biology course for nonmajors, covering standard scope and sequence requirements. The text includes interesting applications and conveys the major themes of biology, with content that is meaningful and easy to understand. The book is designed to demonstrate biology concepts and to promote scientific literacy.
The Double Helix - BioInteractive
The research done by Franklin, Gosling, and Chargaff supports the claim that DNA is a double helix with strands running in opposite directions, between which A pairs with T and C pairs with …

Short Film The Double Helix Educator Materials - HHMI
The film The Double Helix describes the trail of evidence James Watson and Francis Crick followed to discover the double-helical structure of DNA. Their model’s beautiful and simple …

The Double Helix - BioInteractive
The Double Helix. INTRODUCTION. This activity explores the research shown in the short film. The Double Helix, which tells the story of how DNA’s structure was discovered. PROCEDURE. …

DNA TOPOLOGY - University of Texas at Austin
2. The DNA superhelix is also a double helix; it may be plectonemic (prokaryotes) or solenoidal (eukaryotes); Here rather than two strands, two double helical segments coil around each …

3. 4. - University of Houston
The DNA double helix is held together by two types of bonds, covalent and hydrogen. Covalent bonds occur within each linear strand and strongly bond the bases, sugars, and phosphate …

Geometry of the DNA Double Helix - Colorado State University
Geometry of the DNA Double Helix. Jesse Drendel, Moriah Echlin, Lauren Je ers, and Myla Kilchrist. Department of Mathematics Colorado State University. Math 474, Spring 2011. …

The Double Helix TEACHER MATERIALS - BioInteractive
KEY CONCEPTS AND LEARNING OBJECTIVES. • DNA replication is semiconservative. After participating in this activity, students will be able to: Explain that DNA replication is …

DNA Structure: A-, B- and Z-DNA Helix Families - Boston …
Pictures of the double helix of deoxyribonucleic acid (DNA) have become so common that everyone is familiar with its overall shape and structure (Figure 1a).This structure is known as …

Genes and Life 13.3 The Double Helix Structure of DNA
The structure—both how the nucleotides are covalently bonded and how the strands pack together—contributes to the function of DNA. Understanding how DNA performs its many …

Assembly and Characteristics of Nucleic Acid Double Helices …
D-displacement from the helix axis. By virtue of the symmetry axis we discussed above, in a double stranded nucleic acid, there exists a helix axis which is defined by the average …

DNA - The Double Helix - Los Gatos Union School District
Oct 23, 2015 · In 1953, James Watson and Francis Crick established the structure of DNA. The shape of DNA is a double helix, which is like a twisted ladder. The sides of the ladder are made …

Short Film The Double Helix Educator Materials - BioInteractive
The film The Double Helix describes the trail of evidence James Watson and Francis Crick followed to discover the double-helical structure of DNA. Their model’s beautiful and simple …

DNA - The Double Helix - Deer Valley Unified School District
In 1953, James Watson and Francis Crick established the structure of DNA. The shape of DNA is a double helix (color the title black), which is like a twisted ladder. The sides of the ladder are …

Rosalind Franklin and the Double Helix
structure. DNA is a double-helical molecule roughly in the form of a spiral staircase. The double-helical molecule, con-

70 years of the DNA double helix: An interview with Daniela …
Daniela Rhodes spoke with about the discovery of the double helical structure of DNA in 1953 Molecular Cell and its impact on modern science. She discusses how she started working with …

Great Discoveries in Science: The Double Helix - BioInteractive
Great Discoveries in Science: The Double Helix. [JUDSON:] In the early twentieth century, physicists and chemists unlocked secrets of the atom that changed the world forever. But life …

The double helix: a tale of two puckers - Nature
The double helix: a tale of two puckers. Alexander Rich. The era of the double helix began 50 years ago with publication of the Watson-Crick formulation1 and the fiber X-ray diffrac-tion...

DNA: the Double Helix or the Ribbon Helix? - viXra
An alternative model of the structure of the DNA molecule called a ribbon helix is proposed. Unlike the double helix, in it two chains are not intertwined, but go in parallel; unlike another earlier …

The Double Helix - BioInteractive
INTRODUCTION. In the 1950s, James Watson and Francis Crick suggested a mechanism for the replication of DNA, which they called the “Semiconservative Model of Replication.” During …

Artificial Double-Helix for Geometrical Control of Magnetic …
double-helix formed of two twisted and overlapping cylindrical nanowires (Figure 1). The double helix combines dipolar (Figure 1a) and exchange (Figure 1b) coupling with geometrically induced chirality (Figure 1c), giving rise to a rich magnetic energy landscape. To experimentally realize this system, we have 3D-printed

DNA - The Double Helix
DNA - The Double Helix Recall that the nucleus is a small spherical, dense body in a cell. It is often called the "control center" because it controls all the activities of the cell including cell reproduction, and heredity. Chromosomes are microscopic, threadlike strands composed of the chemical DNA (short for deoxyribonucleic acid).

Sharpe Mixers Impeller Technology Brochure - Morrow Water
• Single and double helix impellers are best for blending viscous liquids (NRe<50) • Can be used in conjunction with anchor, auger, axial flow impeller, and/or scraper blades Prop 1.0: • Standard 3-blade propeller • Designed for small diameter high-speed applications • Electro-polished, rubber, or halar coating available F L O W F L O W

Superconducting Double-Helix Accelerator …
conductors. The double helix design, however, facilitates the use of pre-reacted, brittle conductors for such applications. In this paper we describe some of the characteristics of double-helix magnets for accelerator applications and show how a double-helix dipole model magnet (DHD002) was designed and constructed.

Charge Transport along the l-DNA Double Helix
the double helix with a buffer environment leading to larger conductivity. Several channels may contribute to the charge transport along the DNA double helix; they include electronic con-duction along the base pair sequences, ionic conduction associated with the …

Decoding, reading and writing: the double helix theory of …
of teaching, The Double Helix of Reading and Writing.It is argued that this model provides a rationale for a balanced approach to teaching, and an alternative to synthetic phonics. Key words: teaching reading, teaching writing, decoding, the balanced approach, synthetic phonics Introduction How young children can best be taught to read is his-

'Z-RNA'-a left-handed RNA double helix 1 - Nature
RNA double helix Kathleen Hall, Phillip Cruz, Ignacio Tinoco Jr, Thomas M. Jovin* & Johan H. van de Sande*t Chemistry Department and Laboratory of Chemical Biodynamics,

DNA - The Double Helix - Pasco County Schools
is a double helix, which is like a twisted ladder. The sides of the ladder are made of alternating sugar and phosphate molecules. The sugar is deoxyribose. Color all the phosphates red (labeled with a "p"). Color all the deoxyriboses blue (labeled with a "D"). The rungs of the ladder are pairs of 4 types of nitrogen bases. The bases are known ...

Origami DNA model
able to see the shape of a DOUBLE HELIX. 11. Straighten out the sides of the DNA model (the DNA “backbones” ) to make them perpendicular to the creases in the middle (as in step 3). Take care not to uncurl the spiral shape. *Fix your DNA model so that all the creases are neat. This will reinforce the spiral shape. The DNA “backbone” 4

The double helix. A personal account of the discovery of the …
The Double Helix. A Personal Ac-count of the Discovery of the Structure of DNA James D. Watson, Harvard University, Cambridge, Mass. Atheneum Pub-lishers, 162 East 38 Street, New York, February, 1968. xvi + 234 pp. Il-lustrated. 14 X 22 cm. $5,95. The discovery of the structure of DNA, the “secret of life,” is “perhaps the most famous ...

The Double Helix - BioInteractive
The Double Helix THE PULSE PHASE Using this technique, Meselson and Stahl grew E. coli on a medium containing 15N for many generations. This ensured that all of the DNA would be labeled with 15N. As the bacteria grew and reproduced, they incorporated the 15N isotope. This is referred to as the pulse phase of the experiment (i.e., the pulse is

Short Film The Double Helix Educator Materials - HHMI
The Double Helix IN-DEPTH FILM GUIDE DESCRIPTION The film The Double Helix describes the trail of evidence James Watson and Francis Crick followed to discover the double-helical structure of DNA. Their model’s beautiful and simple structure immediately revealed how genetic information is stored and passed from one generation to the next.

Probing Protein-DNA Interactions by Unzipping a Single DNA …
Single DNA Double Helix Steven J. Koch, Alla Shundrovsky, Benjamin C. Jantzen, and Michelle D. Wang Department of Physics, Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853 USA ABSTRACT We present unzipping force analysis of protein association (UFAPA) as a novel and versatile method for

A novel form of RNA double helix based on G·U and C·A …
for the full-length RNA structure (fl helix) suggest that the double helix exhibits A-RNA conformation with helical periodicity of 10.96 bp, similar to canonical A-RNA, which has 11 bp per helical turn (Table 2; Schindelin et al. 1995; Olson et al. 2001). The RNA double helix can be divided into three helical segments of 6 bp each with the ...

Assembly and Characteristics of Nucleic Acid Double Helices …
If the base pair is imbedded in a helix, then there are several more angular attributes of the base pair that we must consider: 1) D-displacement from the helix axis. By virtue of the symmetry axis we discussed above, in a double stranded nucleic acid, there exists a helix axis which is defined by the average symmetry axes of the base pairs.

HANDOUT- Constructing a Paper Helix 2005 - West Linn …
segment of a DNA double helix and then join them to form a large ladder like helix. Procedure 1. Color the bases according to the following color code. Then, cut out the patterns of deoxyribose, phosphate groups, and bases provided. Deoxyribose: BLACK OR GRAY Phosphate: WHITE Adenine: BLUE Guanine: GREEN Thymine: RED Cytosine: YELLOW 2.

DNA - The Double Helix - Mrs. Cowley--- SCORE Academy
DNA - The Double Helix Recall that the nucleus is a small spherical, dense body in a cell. It is often called the "control center" because it controls all the activities of the cell including cell reproduction, and heredity. Chromosomes are microscopic, threadlike strands composed of the chemical DNA (short for deoxyribonucleic acid).

Double Helix Nodal Line Superconductor - Physical Review …
Oct 2, 2017 · bles a closed DNA double helix. An integer Gauss linking number[15, 16, 26] n L can be deﬁned for such two nodal lines, which is equal to the total number of coils of the double helix (up to a sign). However, one must note the linking number n L reverses sign under time-reversal transformation, so a dou-ble helix cannot be TRI by itself.

ORGANIC CHEMISTRY A solid noncovalent organic double …
A solid noncovalent organic double-helix framework catalyzes asymmetric [6 + 4] cycloaddition Tianyu Zheng, Nils Nöthling, Zikuan Wang, Benjamin Mitschke, Markus Leutzsch, Benjamin List* Whereas [4 + 2] cycloadditions are among the most powerful tools …

CSIRO DNA model - Edublogs
bottom of the double helix. 8. Acknowledgements CSIRO's Double Helix Science Club would like to acknowledge all our club members who sent in designs for a double helix model. We would especially like to thank member Angela Smith whose design served as the inspiration that led to the construction of this model. The Helix magazine's former editor ...

DOUBLE HELIX PICKUP - Squarespace
DOUBLE HELIX PICKUP The Double Helix is a magnetic soundhole pickup for steel string acoustic guitars. It fits soundholes with a minimum diameter of 90mm, about 3.5”. The pickup features two switches on the base-plate of the pickup: • The PHASE switch allows you to adjust the phase of the pickup, so the Double Helix will

The Double-Helix of Learning - Canadian School Libraries
The Double-Helix of Learning Nearly 70 years ago, Francis Crick and James Watson ushered in the new era of modern biology when they first published the now ubiquitous double-helix DNA structure first drawn by Crick’s wife Odile. A DNA double-helix consists of two complimentary strands of nucleotide bases held together by hydrogen bonds.

Genes and Life 13.3 The Double Helix Structure of DNA
by twisting the strands of DNA into a double helix, a spiral consisting of two strands that coil around a central axis (Figure 13.6). The base pairs are parallel to each other, perpendicular to the axis of the DNA molecule, and separated by 0.34 nm, the same distance calculated from the diffraction pattern. In addition, Franklin’s results also

Generation of Elliptically Polarized Terahertz Waves from …
Mar 21, 2012 · double helix electrodes, which is made from two copper wires with a 1 mm diameter, was mounted along the plasma region. The two copper wires were twisted for only one period along the grooves on a plastic mount, which has an inner diameter of 4 mm and an outer diameter of 6 mm. The inter spacing is around 5 mm and the length of one pitch is 30 mm.

Aberration correction method based on double-helix point …
potential of the double-helix PSF in aberration correction, because the shape of aberration-free double-helix PSF based on GL modes somehow deviates from the ideal double-helix shape, which makes it difficult to depict the distortions. 31 Recently, an approach to generating the double-helix PSF based on spiral phase 38 was developed and proved ...

Commentary: The Double Helix: Science and Myth in the …
the double helix, was, in a sense, in-cidental. The key to the replication of the gene was the specific pairing of unlike bases, A with T, G with C (to use the accepted single-letter abbreviations--all the detail needed here, Watson 1965). Three books provide very different views of the solution to the problem of the chemical structure of DNA ...

Combing a double helix - Harvard University
May 1, 2022 · helix with initial angle a B P/R and helix radius R extended to final angle a 1 and helix radius R 1; 18 see Appendix for details). Not surprisingly, we find that the force-extension curve for combing a double helix shows a flattening (softening) in contrast with the divergent response for a single helix that is Fig. 1 Tangles in hair. (a) Curl ...

Double helix conformation, groove dimensions and ligand …
antiparallel double helix with Watson-Crick base pairing which is enforced by restraints during refinement. This is commonpractice in nucleic acid refinement (Westhofet al., 1985) and has been applied in all structure analyses performedin ourlaboratory (Heinemannet al., 1987, 1991; Lauble et al., 1988; Heinemann and Alings, 1989, 1991).

The Double Helix Theory of the Magnetic Field - Leedskalnin
The double helix is rotating about its axis with a circumferential speed equal to the speed of light, and the rotation axis represents the magnetic field vector H. The tension in the lines of force is the cause of magnetic attraction between unlike magnetic poles. The double helix lines of force will behave like helical

70 years of the DNA double helix: An interview with Daniela …
structural biologist, some of the landmark studies that were inspired by the double helix, and the exciting challenges ahead. April 25th marks 70 years since three seminal papers were published in 1953 describing the structure of DNA: one from James Watson and Francis Crick of Cambridge University that proposed the structure of the DNA double ...

© 1995 Nature Publishing Group http://www.nature.com/nsmb
Structure of an RNA double helix including uracil-uracil base pairs in an internal loop Katrien J. Baeyens1, Hendrik L. De Bondt 1 and Stephen R. Holbrook The crystal structure of the RNA ...

The Double Helix - colemanhonorsbio.weebly.com
The Double Helix Historic figures, film synopsis, and discussion questions1 Historic figures, Cambridge University James Watson (1928–). Geneticist, codiscoverer of the double helix, Nobel Prize in Physiology or Medicine 1962, headed Cold Spring Harbor Laboratory on Long Island, NY; headed Human Genome Project 1988–92. Francis Crick (1916 ...

DOUBLE HELIX OF PHYLLOTAXIS - ResearchGate
2 Double Helix of Phyllotaxis The research of Bravais’ brothers [1], published about 250 years ago, laid the foundation for mathematical phyllotaxis , the history of which is beautifully

DNA - The Double Helix strands composed of the - Biology …
The DNA helix is actually made of repeating units (monomers) called nucleotides. The combination of a single base, a deoxyribose sugar, and a phosphate make up a nucleotide. Color the nucleotides in the box using the same colors you used for the double helix. The two sides of the DNA ladder are held together loosely by hydrogen bonds between the

Photon efficient double-helix PSF microscopy with …
of the double-helix point spread function versus astigmatism and biplane,” Appl. Phys. Lett. 97 (16), 161103 (2010). 18. M. Speidel, A. Jonás, and E.-L. Florin, “Three-dimensional tracking of fluorescent nanoparticles with subnanometer precision by use of off-focus imaging,” Opt. Lett. 28

A double-helix dislocation in graphene - Nature
a double-helix DNA-like structure with controlled pitch. Pascal Pochet 1 & Harley T. Johnson 2,3,4 1Department of Physics, IriG, Univ. Grenoble-Alpes and CEA, Grenoble, France.

The conformation of the DNA double helix in the crystal is …
forms of the double helix: A-, B- and Z-form DNA1-s. These studies have demonstrated that the DNA double helix adopts a highly variable structure which is related to its base sequence. The

NEWS AND VIEWS Unwinding the Double Helix - Nature
Unwinding the Double Helix J<..:vER ;;incc 'Vatson and Crick proposed in 1 953 that the structure of DNA is a double helix of two strands held together by hydrogen bonds, molecular biologists have ...

Build a Paper Model of DNA pdb101.rcsb
exposed in the two grooves of the double helix: the wider major groove and the narrower minor groove. These edges are also used to carry information that is read by proteins that interact with the double helix. Cut out the model. Fold all long creases ﬁrst. Solid grey lines should be visible on the crease. Fold dotted grey lines so they are

Can the double helix be parallel? - Wiley Online Library
Since the proposal of the double helix for DNA by Watson and Crick,’ many investigators have asked the question, “Is the right-handed antiparallel double helix the only structure for nucleic During the last decade, apart from the classical right-handed antiparallel double helix, it has been shown both by theoretical

Direct Imaging of DNA Fibers: The Visage of Double Helix
Oct 24, 2012 · higher magniﬁcation DNA ﬁber details; the red arrows point out the 2.7 nm pitch of A double helix. The scale bar corresponds to a length of 20 nm. In panel b, a white rectangle is superimposed, showing where the intensity proﬁle was measured. The peaks in plot c correspond to the alternation of

High-resolution atomic-force microscopy of DNA: the pitch …
known pitch of the double helix. The right-handedness of the double helix is directly discernible in high resolution AFM im ages. Thus, this approach can be readily applied to the study of DNA-protein interactions, as well as sequence mapping at high resolution. Key words' Atomic force microscopy (AFM): DNA: Double helix: Resolution; Bilayer ...

Chapter 1 Introduction to Charge Transfer and Charge …
The DNA double helix is formed when two single strands combine to form an extended array of A-T and G-C base pairs. The helix is held together by hydrogen bonding between the complementary bases and stabilized by their stacking interactions. The structurally well-defined DNA π stack may represent a unique medium for electron transfer.

THE DOUBLE HELIX IN ARCHITECTURE AND ENGINEERING
contained a double helix reinforced concrete floor structure that could be interconnected at any location simply by tunnelling horizontally through the central pillar of rock. The gently sloping ramps of the helix providedfor parking and access. Now the last parking place was not at the bottom, but at the top. Ventilation was easy; only one cavern.

The double helix of organizations: Social Performance
This paper presents the notion of double helix through which the organizations with a high level of absorptive capacity (Cohen and Levinthal, 1990) can follow two different paths when they develop ...

feature The double helix and the ‘wronged heroine’
The Double Helix: A Personal Account of the Discovery of the Structure of DNA (Atheneum, New York, 1968). 2. Sayre, A. Rosalind Franklin and DNA (W. W. Norton & Co., New York, 1975). 3. Klug, A ...

The Making of the Fittest: Natural Selection and The Making …
The Double Helix 6. Scientists build models based on what they know from previous research to derive testable hypotheses. Independently, both Watson and Crick and their competitor Linus Pauling constructed an incorrect triple-helix model with the nitrogenous bases arranged so they were on the exterior of the molecule and the

DNA double helix, a tiny electromotor - Nature
Nature Nanotechnology Letter https://.org/10.1038/41565-022-01285-z M All-atom molecular dynamics simulations General simulation protocolUnlessspecifiedotherwise,all ...

Double Helix Hydrogen Bonds - Weebly
The double coiled shape of DNA is called a ___Double___ __Helix__. 2. In order for DNA to begin replication __Hydrogen__ ___Bonds_____ between nitrogen bases must break. 3. ... double helix uracil nitrogen base two deoxyribose sugar hydrogen bonds adenine . …

Genesis of the enzyme that divides the DNA double helix …
double helix during cell replication October 15 2014, by Justin Eure Averaged electron microscope images of two intermediate helicase structures.