During the war, although he continued to teach, Calvin gave up his research to work for the National Defense Research Council and, later, as part of the Manhattan project charged with developing the atomic bomb, where he developed a process for procuring pure oxygen from the atmosphere that has since had significant peace-time applications for medical patients with breathing problems. Resuming his research at Berkeley after the end of the war, Calvin studied the physical and chemical properties of organic compounds, writing The Theory of Organic Chemistry and The Chemistry of Metal Chelate Compounds His clear understanding of the nature of organic molecules was to prove valuable in his subsequent work in biological chemistry.
He formed the bio-organic chemistry group, which later expanded to the Laboratory of Chemical Biodynamics, in the Lawrence Radiation Laboratory of the University of California in Working with his University of California associates, Calvin used the radioactive isotope carbon—which had become available to scientists in —as a tracer for investigations of complex organic chemical systems. They described these tracer techniques in Isotopic Carbon In Calvin's research, chorella, a green algae, was suspended in water and then exposed to light.
Then carbon dioxide consisting of carbon was added. When the algae went through its life processes, producing carbohydrates from the carbon dioxide, water, and minerals, the presence of carbon could be traced using a new research tool, paper chromatography. The series of compounds containing the radioactive carbon at different stages of photosynthesis were thus identified, and the biochemical mechanism of photosynthesis was mapped. Calvin's proposal that plants change light energy to chemical energy by transferring an electron in an organized array of pigment molecules and other substances was substantiated by research in his laboratory and elsewhere.
Calvin tested his theories of the chemical evolution of life with studies of organic substances found in ancient rocks and of the formation of organic molecules by irradiation of gas mixtures, thus simulating the atmosphere thought to exist on earth billions of years ago. These findings were described in Chemical Evolution At first, the Chicago group refused to acquiesce, but it soon recognized its failure and the polemic was defused.
With the first product identified as a known metabolite, the remaining members of the glycolytic sequence were identified by their chemical behavior.
The prior labeling of fructose confirmed the predicted sequence of reactions. Two sugars separated on the paper chromatograms intrigued Benson, who examined their reactivities and recognized them as ketoses. With the able collaboration of James A. Bassham the compounds were subjected to periodate degradation. Benson doubly labeled the smaller of the sugars with 32 P and 14 C and measured their ratio, 2 phosphorus atoms to 5 carbon atoms.
The pentose diphosphate could have few possible structures and they were identified radiochromatographically. Still, there was no indication of the two-carbon precursor of phosphoglycerate.
The list of conceivable two-carbon CO 2 acceptors was exhausted. Nature had securely camouflaged its mechanism of the carboxylation process. Experiments restricting uptake of CO 2 led to increased levels of the five-carbon ribulose bis-phosphate, a logical indication that it could be the CO 2 acceptor molecule.
Though they recognized this fact, it was not immediately obvious that nature had chosen to add CO 2 to a five-carbon acceptor and cleave it to produce two molecules of phosphoglycerate. Melvin Calvin's mind, constantly on the move, recognized the relationship and explained a possible mechanism for dismutation, simultaneous oxidation of one car-.
Nature had devised an efficient process that organic chemistry had failed to match. Cyclic regeneration of the CO 2 acceptor was basic to the thought of Ruben and Kamen and others concerned with photosynthesis. Recognition of the novel carboxylation mechanism closed the cyclic sequence since all the necessary intermediates were then known. For some time in he stopped in at the Old Radiation Laboratory ORL daily to assist with crystallization of the dark product.
The ORL and its work on photosynthesis attracted countless scholars from abroad. She was allowed to visit the laboratory in ORL, but she was not allowed into the restricted areas of the nuclear physics research efforts. Tamiya visited Berkeley to do C experiments to demonstrate photorespiration, the effects of oxygen in inhibiting plant productivity, which he had recognized during the war from his kinetic data.
Tamiya's C experiments with the Riken cyclotron had been terminated by the war. Tamiya was the chief guide for Vannevar Bush, Harry Kelly, and a host of scientist visitors during the American occupation.
Skillful in English, trained in Germany and. France, and a scholar of the classic culture of Japan, Tamiya gained access to the upper echelons of American science and photosynthesis research in particular. He was singularly effective in bringing the finest of young Japanese scientists to American laboratories.
As international relationships were restored, Tamiya was an international leader for two decades. The experiments he attempted with Benson in ORL were the first steps toward recognition of a major aspect of photosynthetic metabolism and its relationship to agricultural productivity. For a few weeks in Ernest Lawrence and Philo Farmsworth came through the laboratory almost daily on their way to Harry Powell's glassblower's shop, carrying their prototype television tube model, which later appeared as the Sony Trinitron.
He also served as president of the Pacific Division of the American Association for the Advancement of Science and on important committees of the National Academy of Sciences including the chairmanship of the Committee on Science and Public Policy. All of this service constituted an admirable contribution to the functioning of these important scientific organizations and to the scientific and scholarly progress of the nation.
Calvin's simultaneous service to the U. Of the many advisory posts listed in. The entire effort that NASA mounted to search for life in extraterrestrial space was greatly influenced by Professor Calvin's participation and advice. His efforts included 1 plans to protect the Moon against biological contamination from the Earth during the first lunar landing Apollo , 2 procedures to protect the Earth from possible lunar pathogens on and in the returning Apollo spacecraft, 3 strategies for the search for organic and biological compounds in returned lunar samples, and 4 plans for the search for biological compounds for life on other planets.
Professor Calvin served the Executive Office of the President in two ways. From to he was a member of the President's Science Advisory Committee. At the conclusion of that service, President Ford wrote to Calvin:. Throughout the past nine months, while we were awaiting creation of the Office of Science and Technology Policy, you and your colleagues were of great assistance to me and to our country in focusing attention on issues vital to our Nation which have involved science and technology.
Your advice and counsel have helped give the new Office of Science and Technology and the president's Committee on Science and Technology a head start in carrying out their responsibilities.
Professor Calvin also served on a number of international groups dedicated to the progress of world science. Fletcher wrote to Calvin:. I want especially to thank you as Chairman of the Editorial Board who worked so diligently toward the completion of these volumes in a most challenging and unusual context requiring the greatest tact and persistency. The result is a truly comprehensive and systematic treatise dealing with the problems of space biology and medicine.
At the memorial service for Melvin Calvin held on January 25, , in Hertz Hall on the Berkeley campus, Glenn Seaborg, one of the authors of this memoir, made the following remarks:. I met Melvin Calvin 60 years ago when he arrived at Berkeley in to assume his instructorship in the Department of Chemistry.
At that time I was serving as the personal research assistant of the famous Gilbert Newton Lewis. Melvin soon began to work on the theory of the color of organic substances. Melvin and I and a number of our bachelor friends lived in the Faculty Club, he in the Tower Room and the rest of us in the second story wing above the present Heyns Room.
I recall that Joe Kennedy and I used to join Melvin in his room to imbibe alcoholic drinks which put us in a good mood for flirting during dinner with the girl waitresses in the Club's main dining room, which is now the Kerr Room.
Melvin was more successful at this than Joe and I. Melvin and I were especially close and I have much to thank him for.
I remember that he was responsible for breaking the ice to enable me to start a serious courtship of my wife, Helen. I had been trying unsuccessfully to date Helen but Melvin found a way. He induced her to accompany him to the Oakland Airport to meet me as I arrived home from a trip East in August of He put his Oldsmobile convertible at my disposal and after delivering Melvin home I brought Helen home along a long circuitous route that enabled me to get much better acquainted with her.
I took advantage of Melvin's Oldsmobile to get even better acquainted with Helen during the ensuing months and we became engaged in March , just before I left for Chicago to work on the Plutonium Project of the Manhattan Engineer District, culminating in our marriage in Nevada in June during a return visit to the West Coast.
A couple of months later, upon a return trip, I found a telegram from Melvin inviting me to be his best man at his wedding, scheduled for October 4. Later that morning I served as best man at Melvin's marriage to Genevieve Jemtegaard. I congratulated him heartily for having the good taste to marry a Scandinavian. The ceremony was followed by a lunch for all the guests at the Claremont Hotel in Berkeley. Later Melvin and Genevieve left for their honeymoon and I don't have any details to present regarding their activities on this occasion.
Their marriage led to three children, daughter Elin Mrs. Sowle and Karole Mrs. Campbell and son Noel, six grandchildren and two great-grandchildren. Genevieve died of cancer in Melvin conceived and led the development of the thenoyltrifluoroacetone TTA solvent extraction process for the separation and decontamination of plutonium.
Although this process was not developed in time to be used in the plutonium production plant at the Hanford Engineer Works during the war, the use of TTA in separation processes proved very useful in laboratory work during the ensuing years. Right after the war Melvin began his seminal research on photosynthesis using carbon as a tracer, which led to his brilliant elucidation of this vital process.
This culminated with his receipt in of the coveted Nobel Prize in Chemistry. The following April, President John F. Kennedy had his remarkable dinner at the White House for 49 Nobel Prize winners. This was the occasion when Kennedy made his famous ad lib remark approximately as follows: This is the greatest gathering of brains in the White House since Thomas Jefferson dined here alone. I won't try to speak of Melvin's many other outstanding scientific discoveries and achievements.
Let me just conclude by reiterating that I have been close to Melvin during these 60 years. I regard him as one of the best friends I ever had. Two areas of research were emphasized: 1 artificial photosynthesis, the concept of using solar energy conversion and modeled after natural photosynthesis and 2 the determination of whether or not certain plants could produce hydrocarbon-like materials that could be used as substitutes for fuel and chemical feedstocks.
Melvin Calvin engaged in an extraordinarily broad range of significant scientific activity, of which his role as Mr. Bassham and Marilyn Taylor, dedicated secretary to Melvin Calvin from to the present. Glenn T. With G. The color of organic substances. The Theory of Organic Chemistry. New York: Prentice-Hall. With A. The path of carbon in photosynthesis. With C. Heidelberger, J. Reid, B. Tolbert, and P. Isotopic Carbon. New York: John Wiley.
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A cell is the smallest unit that is typically considered alive and is a fundamental unit of life. All living organisms are composed of cells, from just one unicellular to many trillions multicellular. Cell biology is the study of cells, their physiology, structure, and life cycle.
Teach your students about cell biology using these classroom resources. Plants are autotrophs, which means they produce their own food. They use the process of photosynthesis to transform water, sunlight, and carbon dioxide into oxygen, and simple sugars that the plant uses as fuel. These primary producers form the base of an ecosystem and fuel the next trophic levels.
Without this process, life on Earth as we know it would not be possible. We depend on plants for oxygen production and food. Learn more about this vital process with these classroom resources. Photosynthesis is the process by which plants use sunlight, water, and carbon dioxide to create oxygen and energy in the form of sugar. The Calvin cycle is a process that plants and algae use to turn carbon dioxide from the air into sugar, the food autotrophs need to grow.
Carbon sinks absorb more carbon than they release, while carbon sources release more carbon than they absorb. Join our community of educators and receive the latest information on National Geographic's resources for you and your students. Skip to content. Twitter Facebook Pinterest Google Classroom. Article Vocabulary. The Calvin cycle goes round and round.
Illustration by Tim Gunther. Calvin cycle. Melvin Calvin. National Medal of Science. Nobel Prize. Media Credits The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit. Media If a media asset is downloadable, a download button appears in the corner of the media viewer.
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