The History of DNA
The scientists who discovered Dna
Born in 1822
In monastery known for
research and teaching
After his death (1884) acknowledgment of his
discoveries in 1900
Known as “The Father of Genetics“
First scientist to describe how traits are inherited
Looked at pea plants for 8 years
He studied 9 generations of plants
He noticed that peas are easy to breed for pure traits and he called the pure strains purebreds.
He developed pure strains of peas for seven different traits (i.e. tall or short, round or wrinkled, yellow or green, etc.)
He crossed these pure strains to produce hybrids.
Mendel crossed purebred tall plants with purebred short plants and the first generation plants were all tall.
When these tall offspring were crossed the result was a ratio of 3 tall to 1 short.
Strong Hereditary traits cover weak traits.
Mendel called stronger traits
DOMINANT – Represented by CAPITAL LETTER (T)
Mendel called weaker traits
Recessive – Represented by lower case letter (t)
Worked in the 1920’s
Taxonomist – a scientist who classifies and names organisms – He specialized in pathogens (disease-causing organisms)
Used mice and bacterium (Streptococcus pneumonia) to see if inherited material is passed though DNA or protein.
Continued Griffith’s work
Identified DNA as the material that passes on the inherited information.
He used large amounts of bacteria and a process of heating and mixing the liquids to extract the nitrogen bases away from the protein
Became world’s first genetic engineer
In 1950, biochemist Erwin Chargaff found that the arrangement of nitrogen bases in DNA varied widely,