According to (Watson, 2001), there are a number of scientists that were involved in studies with an objective of convincing the society as well as science that the molecule of heredity is DNA. The first one was Fredrick Griffith who performed a number of experiments on two bacteria strains; one was not harmful to mice while the other killed them. When he used bacteria’s dead cells to inject the mice, they survived but when he combined the dead bacteria with the live one, all mice died. Therefore, he made a conclusion that the harmless bacteria’s hereditary material was transformed by something that was contained in the dead cells.
This led to other experiments by Oswald Avery, Maclyn McCarty and Colin Macleod so as to identify that transforming factor. They isolated molecular components of bacteria cells that were dead and they were able to determine that the agent involved in the transformation of live bacteria that was harmless into killers was DNA. Others were works by Martha Chase and Alfred Hershey whose experiments made it clear that its not protein but DNA that causes infection when bacterium is infected by bacteriophage. Maurice Wilkins and Rosalind Franklin obtained images of DNA through diffraction of X-ray which answered questions on the mechanisms as well as structure of DNA. DNA’s structure of three dimensions was made clear by James Watson and Francis Crick by proposing a DNA model which is accepted up to today.
Evidence That DNA Is the Molecule Determining Heredity
Although Fredrick Griffith and Oswald made great contributions in the research of DNA as the molecule that determines heredity, some scientists still believed that proteins were the material of heredity but their debate was quitted by Chase and Hershey. This began when Delbluck in conjunction with Hershey realized that when a bacterium is infected by two bacteriophage’s strains, these viruses could have their genetic material exchanged producing offspring with ineffective capabilities that are different compared to those of their parents. It was not until after a period of six years that Hershey joined with Martha Chase to conduct the blender experiment which was very famous.
Waring blender was used to separate bacteriophage’s protein coating from its core of nucleic acid. This showed that the only portion that was injected to the cell of bacteria was nucleic acid. Further details showed that the portion with capability of transmitting information of genes as well as its replication was nucleic acid. This particular experiment acts as evidence that would provide conviction that the molecule of heredity is DNA. After one year Frank Crick and Watson announced DNA’s structure of double helix suggesting the way genetic information is transmitted. (Sayre, 1975)
The Reason Why History and Science of DNA Is Important In Learning That DNA Is the Molecule of Heredity
(Ravin, 1980), argues that learning about science as well as DNA’s history is very important in the learning of DNA as heredity’s molecule. This is because, one is able to know what made scientists perform many experiments to come up with the conclusion. Actually this was because of the disagreement about the nature of hereditary material in terms of chemical. Some argued that the genetic material was protein since analysis of chemical showed there was a great variation in physical properties as well as chemical composition of protein. These disagreements made the scientists see the need to perform experiments to come up with the exact nature of this heredity material. Finally they realized that genes were found in chromosome which had DNA as well.
Advice to the Companies Selling Sport Supplements and How Knowledge on Science of Weight Loss/Gain Helps In Making Informed Decisions
Sport supplements are those supplements that people involved in sports use regulate their weight so that they are fit to perform in sports. These supplements make it easier to stick to a proper diet. Examples include protein supplement as well as meal supplements which are fast, convenient and economical. The sports people use them while they need to add protein and extra calories to their diet to help gain weight or even use them instead of fattening foods to cut weight.
Others like fat burners help in speeding up of metabolism by boosting their energy as well as reducing their appetite. However though companies selling these supplements make a lot of money it would be appropriate to have them stopped from selling since all they do is advertisement to increase sales without cautioning users on their danger. Their dangers include a rise in blood pressure and heart beat of a person taking ephedra.
This is an example of sport supplements and it’s even worse when those taking it already suffer from heart disease or diabetes. However instead of using the supplements people should be aware that body weight is determined genetically and homeostatic mechanisms will be activated in case of weight loss or gain making it return to its original weight. Homeostatic mechanisms help us in weight maintenance during energy deficit periods which may as well be a mechanism helping humans to survive during famine. Humans store excess energy in form of fats acting as a mechanism to help store energy in times of excess food. Informed decision would be to exercise the body other than using supplements which would otherwise harm one’s body. (Tanaka, 2001)
References
Watson J. (2001): A personal account of the structure of DNA: Touchstone pp. 35-37.
Sayre A. (1975): Rosalind Franklin and DNA: Norton pp. 13-17.
Ravin A. (1980): Science, Values and Human evolution: Blackwell synergy. pp.27-30.
Tanaka S. (2001): Adequate weight reduction: Blackwell Synergy pp. 22-25.