Discovered Modern Genetics Gregor Mendel: Discovered Modern Genetics

I never know the words genetics, chromosomes or genes I never know the words genetics, chromosomes or genes. DNA wouldn’t be discovered for over 100 years. No one knew how traits were passed down.

I went to work in my little garden and 20 years later, I knew how inheritance worked.

Born July 22, 1822 Entered the Augustinian monastery at Brünn, Czech Republic. Carefully analyzed seven pairs of seed and plant characteristics of peas. Between 1856 and 1863 he cultivated and tested at least 28,000 pea plants.

Published his important work on heredity in 1866. Experiments resulted the laws of heredity His work not used for the next 34 years. In 1900, his work recognized by three investigators. He died in January 6, 1884.

Traits of Pea Plants Height Seed Color Seed Coat Color Pod Color Round/wrinkled seed Pod appearance Flower position on stem

What he did… Began with pure-breeding plants Crossed plants with different traits Planted resulting peas Examined offspring plants Wrote down ALL observations Did the math Wrote the laws of inheritance

Parents F1 F2 Actual ratio Probability In your journal, make a five column table and write in headings as listed above.

What results when you cross 2 of the offspring tall plants?

3 tall plants for every 1 short plant

What results when you cross 2 of the offspring round seed plants?

3 round seed plants for every 1 wrinkled seed plant

Let’s look at a few numbers. Write them in your table.

Tall x short Tall 787 Tall 277 Short 2.84:1 3:1 Green Pod X Yellow Pod Parents F1 F2 Actual ratio Probability Tall x short Tall 787 Tall 277 Short 2.84:1 3:1 Green Pod X Yellow Pod Green 428 Green 152 yellow 2.82:1

Yellow seed x Green seed Yellow 6,022 Y 2,001 G 3.01:1 3:1 Round Seed Parents F1 F2 Actual ratio Probability Yellow seed x Green seed Yellow 6,022 Y 2,001 G 3.01:1 3:1 Round Seed x Wrinkled Seed Round 5,474 rd 1,850 wr 2.96:1

Words to know Gene The DNA on the chromosomes. Allele or Alleles The letter(s) we use to represent genes Genotype The letter combinations (like TT, Tt, tt) Phenotype What you actually see (like tall or short)

Words to know Pure (refers to dominant) The letters are the same (TT, RR) Hybrid The letters are different (Tt, Rr)

Words to know Homozygous (refers to dominant) The letters are the same (TT, RR) Heterozygous The letters are different (Tt, Rr) The same as hybrid

Thank you , Mr. Mendel!