What relationship between the nucleotides did Erwin Chargaff discover? | Yahoo Answers
C. The amounts of A and T are equal. The amounts of C and G are equal. D. The amounts of A and T are equal. The amounts of C and G are equal. Or the rule can be stated that there is a ratio of paired pyrimidine. Clicker Questions Learn with flashcards, games, and more — for free. What relationship between the nucleotides did Erwin Chargaff discover? And why?.
From toChargaff studied chemistry in Viennaand earned a doctorate working under the direction of Fritz Feigl.
Erwin Chargaff - Wikipedia
Chargaff had one son, Thomas Chargaff. Chargaff returned to Europewhere he lived from toserving first as the assistant in charge of chemistry for the department of bacteriology and public health at the University of Berlin — and then, being forced to resign his position in Germany as a result of the Nazi policies against Jews, as a research associate at the Pasteur Institute in Paris — Columbia University[ edit ] Chargaff emigrated to Manhattan, New York City intaking a position as a research associate in the department of biochemistry at Columbia Universitywhere he spent most of his professional career.
- CHARGAFF, ERWIN
- Erwin Chargaff
Chargaff became an assistant professor in and a professor in After serving as department chair from toChargaff retired as professor emeritus.
After his retirement as professor emeritus, Chargaff moved his lab to Roosevelt Hospitalwhere he continued to work until his retirement in During his time at Columbia, Chargaff published numerous scientific papersdealing primarily with the study of nucleic acids such as DNA using chromatographic techniques. He became interested in DNA in after Oswald Avery identified the molecule as the basis of heredity. Inhe discovered that the amounts of adenine and thymine in DNA were roughly the same, as were the amounts of cytosine and guanine.
Chargaff's rules[ edit ] Erwin Chargaff proposed two main rules in his lifetime which were appropriately named Chargaff's rules. The first and best known achievement was to show that in natural DNA the number of guanine units equals the number of cytosine units and the number of adenine units equals the number of thymine units.
A phosphodiester bond consists of a phosphate group in which two of the oxygen atoms are bonded to other atoms - in this case, to carbon atoms of the neighboring deoxyribose sugars. The DNA strand consists of alternating phosphate groups and deoxyribose sugars sugar-phosphate backbonewith the nitrogenous bases sticking out from the deoxyribose sugars. DNA nucleotides assemble in chains linked by covalent bonds, which form between the deoxyribose sugar of one nucleotide and the phosphate group of the next.
This arrangement makes an alternating chain of deoxyribose sugar and phosphate groups in the DNA polymer, a structure known as the sugar-phosphate backbone Chargaff's rules One other key piece of information related to the structure of DNA came from Austrian biochemist Erwin Chargaff.
What relationship between the nucleotides did Erwin Chargaff discover?
He made several key observations: They were the first to cross the finish line in this scientific "race," with others such as Linus Pauling who discovered protein secondary structure also trying to find the correct model. Some of their most crucial clues to DNA's structure came from Rosalind Franklin, a chemist working in the lab of physicist Maurice Wilkins.
Franklin was an expert in a powerful technique for determining the structure of molecules, known as X-ray crystallography. When the crystallized form of a molecule such as DNA is exposed to X-rays, some of the rays are deflected by the atoms in the crystal, forming a diffraction pattern that gives clues about the molecule's structure.
Discovery of the structure of DNA
X-ray diffraction image of DNA. The diffraction pattern has an X shape representative of the two-stranded, helical structure of DNA. Image modified from " DNA structure and sequencing: A modern example of the diffraction pattern produced by DNA is shown above.
To Watson, the X-shaped diffraction pattern of Franklin's image immediately suggested a helical, two-stranded structure for DNA 3.