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Gregor Mendel
Studied peapods for years, he then came up with three law; the Law of Independent Assortment, the Law of Segregation, and the Law of Dominance -
Frierich Miescher
extracts nucleic acid, which comes to be known as DNA, from the nuclei of white blood cells. He determined that nuclein was made up of hydrogen, oxygen, nitrogen and phosphorus and there was an unique ratio of phosphorus to nitrogen. -
Walter Sutton and Theodor Boveri
found that a specific assortment of chromosomes is responsible for normal development, and this can mean that the individual chromosomes possess different qualities, and also came to the conclusion that the number of chromosomes is reduced by half in sperm and egg cells, with the original number restored in the zygote, or fertilized egg, during reproduction, which is now known as meiosis. -
Phoebus Levene
Discovered ribose, later on he also discovered the carbohydrate in thymus nucleic acid and that it was also a sugar, and that it differed from ribose because it lacked one oxygen atom - so he called it deoxyribose. He also worked on nucleic acid structure and demonstrated that units were formed by the various components linking together - phosphate-sugar-base. He coined the term nucleotide. -
Thomas Hunt Morgan
He established the "Fly Room" at Columbia to determine how a species changed over time. Developed the ideas, and provided the proof for the chromosomal theory of heredity, genetic linkage, chromosomal crossing over and non-disjunction. -
Frank Griffith
Proved that DNA is a molecule of inheritance. He did four experiments in which he injected strands of bacteria into mice, one strand that was harmless (R) and one that was harmful (S). Griffith found from this experiment that even though he had killed the S cells, he hadn’t destroyed their hereditary material, which was the one part that caused the disease. -
Oswald Avery
DNA was the factor that caused genetic transformation. DNA is the molecule of inheritance, DNA is what genes are made of. -
Erwin Chargaff
regularity of proportions in DNA bases for different species. He discovered that the amount of adenine equals the amount of thymine, and the amount of guanine equals the amount of cytosine. -
Maurice Wilkins
X-ray diffraction pictures done by Wilkins and his co-worker Rosalind Franklin on the aligned fibers within DNA were seen by James Watson and Francis Crick who, incorporating what it revealed, were then able to build an accurate, detailed model of the DNA molecule. -
Hershey and Chase
Helped to convince the world that DNA is genetic material. Did experiments with bacteria, from these experiments it was clear that the DNA component of the bacteria is injected into the bacterial cell while the protein component remains outside. It is the DNA that is able to direct the formation of new virus particles complete with protein coats. -
Rosalind Franklin
Discovered DNA double helix. Franklin was able to get two sets of high-resolution photos of crystallized DNA fibers using an X-Ray crystallography unit. She used two different fibers of DNA, one more highly hydrated than the other. From this she deduced the basic dimensions of DNA strands, and that the phosphates were on the outside of what was probably a helical structure. -
Watson and Crick
Made the discovery of DNA's molecular structure. Two pairs of complementary base would have identical shapes if held together by hydrogen bonds. Two long chains of such base pairs would likely form a double helix—roughly. The DNA molecule, comprised of long strands of base pairs in specific and varied sequences, could embed genetic information that, if the strands were separated, could be copied -
John Sulston
Understood and explained the dividing of cells.