History of DNA

• Gregor Mendel studied the inheritance of different characteristics in pea plants. He observed that the inheritance of each characteristic is determined by 'units' that are passed onto offspring and that some of these units are dominant / overpowered other units.
• Mendel's work was not originally accepted because:

  1. He did not communicate his work properly
  2. He published his work in an obscure journal
  3. He had a lack of scientific backing
• In the 19th century, behaviour of chromosomes during cell division was observed and in the 20th century, it was found that chromosomes and Mendel's 'units' behaved in similar ways. This led to the idea that these 'units' (genes) were located on chromosomes.