In 1908, British physician Archibald Garrod proposed the important idea that the human disease alkaptonuria, and certain other hereditary diseases, were caused by inborn errors of metabolism, providing for the first time evidence that linked genes with molecular action at the cell level. Molecular genetics did not begin in earnest until 1941 when American geneticist George Beadle and American biochemist Edward Tatum showed that the genes they were studying in the fungus Neurospora crassa acted by coding for catalytic proteins called enzymes. Subsequent studies in other organisms extended this idea to show that genes generally code for proteins. Soon afterward, American bacteriologist Oswald Avery, Canadian American geneticist Colin M. MacLeod, and American biologist Maclyn McCarty showed that bacterial genes are made of DNA, a finding that was later extended to all organisms.
The-initial-proposal-of-the-structure-of-DNA-by-JamesThe initial proposal of the structure of DNA by James Watson and Francis Crick, which was …[Credits : Encyclopædia Britannica, Inc.]
Sex-linked-inheritance-of-white-eyes-in-Drosophila-fliesSex-linked inheritance of white-eyes in Drosophila flies.[Credits : Encyclopædia Britannica, Inc.]
Steps-involved-in-the-engineering-of-a-recombinant-DNA-moleculeSteps involved in the engineering of a recombinant DNA molecule.[Credits : Encyclopædia Britannica, Inc.]
Dolly-the-sheep-was-successfully-cloned-in-1996-by-fusingDolly the sheep was successfully cloned in 1996 by fusing the nucleus from a mammary-gland cell of …[Credits : Encyclopædia Britannica, Inc.]
Mendels-law-of-independent-assortment-The-example-here-shows-aMendel’s law of independent assortment[Credits : Encyclopædia Britannica, Inc.]
Mendels-law-of-segregation-Cross-of-a-purple-flowered-andMendel’s law of segregation[Credits : Encyclopædia Britannica, Inc.]
Punnett-square-diagrams-are-used-to-predict-all-the-possiblePunnett square diagrams are used to predict all the possible gene combinations that could result …[Credits : Encyclopædia Britannica, Inc.]
James Watson and Francis Crick revolutionized the study of genetics when they discovered the …[Credits : Acquired from Vast Video]
Specific segments of DNA are amplified (copied) in a laboratory using polymerase chain reaction …[Credits : Encyclopædia Britannica, Inc.]
Studying bacteria has lead to the relatively new science of genetic engineering.[Credits : Acquired from Vast Video]
Advantages of budding and grafting.[Credits : Acquired from Vast Video]
Mendel’s discovery of the fundamental laws governing the science of genetics.[Credits : Acquired from Vast Video]
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