Evolution and Dna

EVOLUTION AND DNA

DNA [Deoxyribonucleic acid] is the blueprint characters in living organisms.  DNA is a long sequence that is expressed in codes. A, T, C and G are the four essential small units that are strung mutually to make up DNA.  These alphabets are used to abbreviate the types of base carried by each unit. Several parts of human’s DNA are functionless while others are control the turning on and off of the genes. Amino acids which are vital for building an organism are made from genes of human’s DNA. Changes in the DNA sequence result to changes in proteins and as a result, there are changes in characters that are controlled by those proteins.

The DNA of an organism affects its behaviors, physiology and even its outlook.  Body cells check the mistakes in the sequence of the DNA during mitosis. Changes in DNA [mutations] are caught before they form a sequence and their cells are destroyed. Nonetheless, some mutations have less effect and they are able to have their way past the checkpoints. As a result, these mutations affect the functioning of an organism.

Improvements of technology over the past century, has allowed scientists to discover the evidence of evolution in DNA.  It has become possible for one to map the genomes of species and compare the maps. Scientists are now able to discover the overlapping and the difference of species by simply entering their genetic information.

As a result of DNA fingerprinting becoming efficient, easier and lucrative, is has now become possible for comparison of different types of species. Through speciation, it is also possible to approximate when two different species diverged.

Though there are no exact links in history, DNA evidence is enough to give a clue of the happenings of olden time. Random mutations are very accurate in measuring the time of species divergence.

REFERENCES

1. Miyata, T., Hayashida, H., Kuma, K., Mitsuyasa, K. & Yasunaga, T. Male-driven molecular evolution: a model and nucleotide sequence analysis. Cold Spring Harbor Symp. Quant. Biol. 52, 863−867 (1987). 

1. Shimmin, L.C., Chang, B.H.J. & Li, W.-H. Male-driven evolution of DNA sequences. Nature 362, 745−747 (1993).