-
Discovery of "Cells"
Robert Hooke (1635-1703) of Britain designed his own microscope and discovered matter made up of what he called cells. -
Cell Theory Created
C.F. Wolff (1733-1794) of Germany proposed a general cell theory. -
Mendel Starts Experiments
Gregor Johann Mendel (1822-1884), an Austrian monk, began experiments with pea plants. He later became known as the "father of genetics." -
Mendel's Laws
Mendel announced his theories of heredity, known as Mendel’s Laws. -
Chromosomes Discovered
German biologist Walther Fleming (1843-1905) used dyes to stain cells; he discovered rods he called “chromosomes.” -
Chromosomal Pairs Discovered
American biologist Walter Stanborough Sutton (1877-1916) demonstrated that chromosomes exist in pairs that are structurally similar. -
Specific Chromosomes Investigated
American biologist Thomas Hunt Morgan (1866-1945) with Alfred H. Sturtevant of the U.S. showed that genes were located on chromosomes; he experimented with Drosophelia (fruit flies) to investigate sex chromosomes, and discovered X and Y chromosomes, sex-linked traits, and crossing-over. -
DNA Announced as Genetic Material
Oswald T. Avery (1877-1955) of the U.S. announced that DNA alone is the substance responsible for heredity. -
DNA Structure Discovered
Francis H. C. Crick (1916- ) of Britain and James D. Watson (1928- ) of the U.S. made a model of the DNA molecule and proved that genes determine heredity. -
Genetic Code Discovered
Scientists are now able to predict characteristics by studying DNA. This leads to genetic engineering, genetic counseling.