Genetics

One of the characteristics of life is the ability to produce offspring and pass on the traits of the parents to the offspring. All organisms on Earth use DNA as the molecule to carry and pass on those traits. Genetics is basically the study of DNA, the genes that code for traits, and how those genes are passed on. Two common themes can be noticed in the study of genetics is how similar we are and how different we are.

Because all living organisms have some basic physiological functions, which must occur for life to continue, all living organisms share many genes. For example, mosquitoes and humans, which are obviously very different organisms, share about 60% of their genes. Within a single species, we can also see a great many similarities. Though there are over 6 billion humans on Earth, we all have about the same body temperature, blood chemistry, and metabolic requirements. All of these similarities stem from an inherited set of genes, which we all have with only minor variations. But, even within a species we can see a great amount of variation. In the case of humans, we can see a wide variety of differences in skin, eye, and hair color, height and weight proportions, and physical abilities. All of these are dictated in part by our genes. Even though we are all basically the same, minor variations in our genes are what make us unique. Another case of differences can be seen in chimpanzees and humans. There is only about a 2% difference between our genes and a chimp’s. As you can see, only a little bit of difference can cause a big change in the evolution of a species.