Review of Mendel’s Genetics

Here I found a great page story-telling  Mendel’s Genetics.Can’t be more suitable as a revision of what we learned about genetics and inheritance in high school.  >>Mendel’s Genetics

I believe by reading the link page you have remembered the principles of Mendel’s Genetics. We’ll  summarize these principles again in next posts.

While Mendel’s research was with plants, the basic underlying principles of heredity that he discovered also apply to people and other animals because the mechanisms of heredity are essentially the same for all complex life forms.”

It must be a cliche to summarize the success factors of Mendel’s experiments, but it has to be done, for many of the factors are still important for today’s experimentalists.

Firstly, before the experiment,Mendel spent a long time observing different traits of the peas and decided which traits he was going to focus on in the after experiments. He was prepared, had anticipation and, perhaps already held some hypothesis of what was going to happen.

Then it was the choice of his “lab-rats”. As the link page says,”Mendel picked common garden pea plants for the focus of his research because they can be grown easily in large numbers and their reproduction can be manipulated. ” Based on a large number of offspring, the resulting statistics can be assumed as very close to theoretic  statistics.  In this case, it’s  way more convenient to study the traits of these peas than those of some fragile and rare pole plants. 

More important, “pea plants have both male and female reproductive organs.  As a result, they can either self-pollinate themselves or cross-pollinate with another plant.  In his experiments, Mendel was able to selectively cross-pollinate purebred plants with particular traits and observe the outcome over many generations.  This was the basis for his conclusions about the nature of genetic inheritance.”

Reproductive
structures of
flowers

drawing of a flower cross-section showing both male and female sexual structures
the picture is from http://anthro.palomar.edu

Last but not least, Mendel was a pioneer in applying Math(Statistics) to experiment analysis. He rounded the ratio of numbers of different traits to a whole number and discovered the astonishing similarity of all the results.

In high school that’s all the factors, but actually there’s more. For one, Mendel succeeded because all the genes that controlled traits he picked to observe happened to be on different chromosomes. Otherwise, the  phenomena of “linkage” would have appeared (which we’ll talk about later)and he should never have had such a groundbreaking discovery.

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