Gregor Mendel and Genetic Research

• Gregor Mendel, an Austrian scientist and monk, is considered the founding father of genetics.
• Farmers had known for thousands of years that crossbreeding the best plants together could lead to more favorable offspring, but nobody understood how it worked.
• Gregor Mendel experimented with pea plants in the monastery gardens and studied how certain traits like the height of the plants, the color of their flowers, and the color of the pea pods was passed on from one generation to the next.
• In one experiment, Gregor Mendel took a green pea plant which had green pods and a yellow pea plant which had yellow pods and crossed the two plants together, resulting in all yellow pea plants in the offspring.
• Gregor Mendel then took two of these offspring yellow pea plants and crossed them together, finding that three quarters of the offspring were yellow but one in every four were green.
• Gregor Mendel concluded that there must be something being passed on from one generation to the next which he called hereditary units, and these units could be dominant or recessive.
• In these experiments, all of these yellow pea plants in the second generation still had the hereditary units for green pods but they just weren't being expressed because they were recessive.
• Gregor Mendel also did the same experiment with other traits as well like the height of the plants and the color of their flowers, finding the same pattern suggesting that lots of different characteristics are passed down in a dominant recessive way.
• Gregor Mendel's discoveries were not recognized until decades after his death, but his work was crucial in understanding how hereditary units, which we now call genes, are passed down from one generation to the next.
• In the 1800s, scientists didn't know about either dna or genes, but by the end of the 1800s, scientists discovered chromosomes and could observe how they behaved during cell division.
• In the early 1900s, scientists noticed the similarities between chromosomes and the hereditary units that Mendel had talked about and they came up with the idea that these units which we now call genes were actually on the chromosomes.
• The other big advances in genetics were in the 1950s when we discovered the double helix structure of dna and in 2003 when we managed to sequence the entire human genome, which means that we figured out the entire sequence of genetic bases that make up human dna.