Y: Hello good afternoon my name is yadira, they are mireya and Andrea and we are engineering students in biotechnology and we are gathered to discuss important to our area scientists

A: I think that isolating the DNA was the greatest step in genetics and biotechnology

Y: I agree with you because of this discovery are derived 100% of researches at the molecular level

M: Yes, ¿ who discovered it?

A: Johan Friedrich Miescher was a Swiss physician and biologist. He isolated various phosphate-rich molecules, to which he called nuclein (now nucleic acids) from the nucleus of white blood cells in 1869, and thus paved the way for identification as the carriers of hereditary information, DNA.

Y: Yes, I read that got their samples from salmon sperm and pus from wounds
M: Friederich besides there are other important scientists such as Watson and Crick were. They discovered the double helix or spiral staircase model of DNA that know and manage today. In its time it was known that the chemical composition of the molecule consisted of four kinds of bases: thymine (T), guanine (G), cytosine (C) and adenine (A) they were linked by weak links in phosphate-sugar, but its structure was unknown. In fact, the way in which these bases also joined was unknown. 

Y: Good but we must not forget the father of genetics Gregor Mendel, was a Catholic Augustinian monk and naturalist born in Austria he described, through the work carried out with different varieties of pea, the now called Mendel's laws governing genetic inheritance.

A: Early works in genetics were made by Mendel. Initially crosses made ​​of seeds, which are particularized to get out of different styles and some of their own way

M: Their results found the key characters that are characterized by determining the effect of a recessive gene and having no genetic effect (say, speech) of a heterozygous phenotype.

Y: Yes, we know that the discovery of DNA acts many scientists. But I think the most important wasMendel because without their investigations had not arisen inquiries.

A: I think the same as you 

M: I agree with you because when you make the first inquiry was started a long way for researchers

Y: So as a result of the comments above we can deduce that the most important was Gregor Mendel and later there were many researchers who contributed to the order, sequence and composition of DNA


you can watch my video in this direcction:
http://acontrerasa.blogspot.com/p/3-semester.html