Then

How many times have you heard that you look just like your Mum or Dad?

Is it your nose? Your eyes? Or perhaps your bad temper? For a lot of these sorts of appearances and behavioural patterns, we can often blame our parents. But, we didn't always know how traits or characteristics could be inherited.

In the middle of the 1800s, a monk named Gregor Mendel methodically recorded the passing of traits from one generation to the next by crossing different pea plants to produce offspring with red or white flowers, and wrinkled or smooth peas. His writings went on to become Mendel’s principles of inheritance.

Knowing that characteristics are passed from one generation to the next led to humans selecting specific plants and animals for breeding. For example:

          • plants with bigger or sweeter fruit
          • plants with the ability to survive in dry conditions or resist disease
          • healthier animals with more meat and less fat.

The different dogs pictured here are examples of selective breeding.

 

Cheese, yoghurt, wine, beer and bread are all made using micro-organisms such as bacteria and yeast. Beer is recorded in Egyptian medical texts from 1600 BC for use as a prescription medicine, and primitive cheese-making tools have been found in Iron Age settlements in Britain.

These uses are often referred to as traditional biotechnology.

Traditional biotechnology poster

South African Public Understanding of Biotechnology Programme

Download this poster on traditional biotechnologies for your classroom - work sheet [PDF 395kb | 1 page]

Or try some traditional biotechnology yourself and make some yoghurt - work sheet [PDF 30kb | 2 pages]