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Revision as of 03:09, 5 October 2016 by imported>S (What is Sequencing in Genomics and Omics? (as an approach of understanding life): new section)

Why Darwin's Evolution theory can be wrong?                                                                                                                         Madina Seidualy   20132023                             

In 1859, Charles Darwin first introduced evolution theory to the world in his “On the Origin of the Species” book. This theory explains about that all creatures of life have been evolved from common ancestry. According to him from the simplest things transformed to the most complicated organisms by natural selection over the long time of period. Precisely, mutation in organisms leads to variation in structure, where mutation help organism to survive in specific environment that organism will preserve that mutation in itself and pass it to the next generations. At the same time, if mutation affords to some abnormalities or make it hard to adapt to the environment, they will not make more offspring and will disappear over the period. That is the main concept of the natural selection, which organism changes over the time by accumulation of different advantageous mutations in their genetic code.

 Nevertheless, Darwin’s evolution theory is argued a lot, since there a lot of misconception and scientific knowledge is usually tentative and subject to change when new evidences or new theories comes out. Furthermore, I would like to describe how this evolution theory can be wrong and give some examples.

Similarities among species. If human beings have similar or same organs such as eyes, lungs, hearts with monkeys it does not mean that we derived from them. In genetics similarities among species defined as homology, degree of the relatedness. However, in this essay I prefer using the word “similarity”, due to it helps to analyze evolution theory accurately.

In life, the majority of animals and plants have huge similarities and it can explained by that they all consisted of same elements: oxygen, nitrogen, carbon, hydrogen. The same thing might be observed in other field, for example, there too many sentences and languages in the world, however all of them made up by only the letter’s combinations. In two words might be all letters be same but only one letter can be different, also like that there can be ten words that differ only in one letter but have absolutely different meanings. Even though there is huge similarities among types of organisms, all species have significant differences between them, which we should not neglected. In addition, humans and other animals mostly feed from the common foods. Despite that, all living organisms varies in many aspects. It is not enough to say that animals derived from each other only looking to their similarities in organs and in their constructions.

Moreover, applying diverse mechanisms for all various creatures in the world is not favorable. On the grounds of that interaction between them would have lost, every type will stay in their world and would be wild. Consequently, in this world would be impossible to live a life.

Darwin's Theory of Evolution is a theory in crisis.  Recent improvements in science afford rewarding results in variety research. Darwin made theory in the concept of that organisms gradually evolves from primitive cells to the multicellular and multifunctional animal and human beings. On the other hand, molecular biologist Michael Denton wrote that "Although the tiniest bacterial cells are incredibly small, weighing less than 10-12 grams, each is in effect a veritable micro-miniaturized factory containing thousands of exquisitely designed pieces of intricate molecular machinery, made up altogether of one hundred thousand million atoms, far more complicated than any machinery built by man and absolutely without parallel in the non-living world."  (Michael Denton, "Evolution: A Theory in Crisis," 1986, p. 250.)

From its cellular level it was not a simple creature, from beginning all organisms own amazing complex systems.

 Charles Darwin did not create this theory all alone, or it did not pop up accidently. Before Darwin, Jean-Baptiste Lamarck bring the idea of the transformational evolution. He first introduced the idea of that organism changes by time according to effect of the environment, and those changes inherited to the next generations. He proposed idea of “use it and lose it”, where using one part of the organism can improve or bring changes in traits and disuse can cause to reduction of that function. Darwin influenced with that idea, and described it in the context of “natural selection”. They provided several examples for “use it and lose it” theory, like formation of long neck in giraffes or wingless birds that evolve wings, and remnant organs in different organism regarded as a useless evolutionary artifact.

However, a new advances in science and technology found new evidences, which did not support evolution theory, afford avenues that evolution theory can be wrong. To give an example, an appendix for a long time was considered as a remnant organ in human body, which lost its function during the evolution. Now, appendix suspected of playing an important immunological role much like that of tonsils and adenoids. Recent studies suggests that this organ is “safe organ” for commensal bacteria in the large intestine. Presence or absence of an appendix reveals no evolutionary pattern, because this organ not found in any invertebrates, amphibians, reptiles, or bird.

Also, according to Lamarck assumption, giraffe gets long neck, due to they constantly tried eating leafs from tall trees, as a result his neck is prolonged. Then it brings question why only giraffes have long neck? Is there any animal, which do not want to eat leaves from tall trees? There is goat, which consumes leafs also, but their neck didn’t get long, instead they jump from rocks to rock to climb and get leaf from trees. The same question, why snake will prefer live without limbs, while the other animals in the same environment uses limbs very well?

 Wingless birds evolve a wing. In evolution, if first wings starts to appear, at first it will be stubs, which is too small for the bird to fly. Why it will continue to evolve if a bird stubs at first is useless? With respect to evolution theory will it be counted as disadvantages in its environment? Thereby, there are some contradictions that leads to misconceptions in theory.   

In a nutshell, Darwin’s evolution theory cannot taken as fact due to it lacks some perfections in its concept.  Until it will proved scientifically, there will be arguments and contrast ideas every time. We cannot make conclusion after looking to the first three or four closed doors among one thousand doors, that all of them are closed.   

 

 

References:

http://www.darwins-theory-of-evolution.com/

Michael Denton, "Evolution: A Theory in Crisis," 1986

http://www.sparknotes.com/biology/evolution/lamarck/section2.rhtml

Duke University Medical Center. "Evolution Of The Human Appendix: A Biological 'Remnant' No More." ScienceDaily. ScienceDaily, 21 August 2009. www.sciencedaily.com/releases/2009/08/090820175901.htm

Why Darwinism Is False” Jonathan Wells ,Discovery Institute, May 18, 2009 http://www.discovery.org/a/10661

 

 

What is Sequencing in Genomics and Omics? (as an approach of understanding life)

What is Sequencing in Genomics and Omics?

(as an approach of understanding life)   Sequencing

Madina Seidualy                   20132023          09/09/2016
 

 First of all, I would like to describe my point of view about life. What is life? Actually, this word correlated with verb “live”, which can be expressed in diverse words like breath, staying alive, surviving, reproducing. “Live your life”, where only living organisms can achieve that. Thereby, Life is noun state of live, only living things own life. All living organisms distinguished from material things as they were constructed from cells, the basic unit of life. All cells are consisted of variety functional organelles or particles, those give priority to survive. The special thing that exist in all cells of entire organisms is DNA, which carrier with them live survival instructions.

It is proved scientifically that DNA in chromosomes of living organisms own information about whole function in the cell, and any mismatch in their structure will lead fail in the function of appropriate organelle or another cell blocks. DNA is the molecule consists of two antiparallel strands of four nucleic acids, which coiled forming double helix. Those four nucleic acids are the monomers of this huge molecule and their base pair were distinguished, either Thymine (T), Cytosine (C), Adenine (A) and Guanine (G). These bases forms with each other, like A-T, G-C, parallel strands. According to the researches, number of base pairs in one cell of human is around 6x10^9, and fascinating fact is that 2,5 m of DNA coiled in so tiny cell nucleus.

Every cell of the human organism equally have that number and length of DNA molecule, however according cell’s function only several sections of the DNA could be read and transcribed and translated. Consequently, whole cell DNA molecule have information of life of that organisms, and variety part of organism cells only read pieces they required and save other parts condensed in nucleus.

 Genomics, if we simplify, want to read those whole DNA base pairs in a cell, so that they could understand their function, effect on, place in and response for their whole genome networks. Moreover, reading possible only by Sequencing DNA, which make scientist to list whole 6 billion codes, consists of A,T,C,G. Until nowadays, most famous and efficient way of Sequencing DNA were Sanger sequencing and Next-generation sequencing.

 In following two paragraphs I will describe shortly about above two sequencing methods. In 1977 – 80 years first Fred Sanger introduced this method to the world, and have been used till mid 2000s. In any sequencing it is impossible to read it without cutting long DNA or interested gene to tiny splices, by restriction enzymes after isolating gene. Afterwards, we have to amplify it to thousands strands, which it possible by PCR (polymerase Chain reaction). Now we have extreme numbers of single strands, the thing we have to do now copy or make its second strands. For that, we require polymer, to start the polymerization, and polymerase, enzyme that makes that action, and a quantity of dNTP, building blocks of DNA. In addition, we need the crucial feature of this method is ddNTP, terminator nucleotides. If ddNTP binds to the elongating strands it stops elongation, and terminated strand at that position. Correspondingly, all four ddNTP will be labelled with different colors, so later we detect them with UV. This experiment should done four times for the same splice of the strand with four ddATP,ddGTP,ddCTP, ddTTP. As a result, different strands terminated at different strands. Those strands we will run on electrophoresis gel, where short sequences run first, the longest ones run as latest. Thereby, that splice’s or gene’s DNA code will be sequenced by analyzing result of the gel electrophoresis.  

 

The second method of the sequencing is next-generation sequencing(NGS), which were applied recently, about 10 years ago. This method also have same beginnings such as isolating DNA, restriction them. The difference is on further steps, in NGS amplification of multiple strands can be used and sequenced at the same. Thereby, PCR of multiple strands have been done, fragment clusters were placed on a flow cell, glass plate. The tremendous feature of this method is that, nucleotides were terminated by labelling fluorescent dyes to the 3’-OH on sugar, which enabled them to form phosphodiester bond and called as reversible terminators. However, in this experiment no need to normal nucleotides. Firstly, all strands will be bind with primers after to that plate added all reversible terminators, then that plate was screened under the UV light. So we can get all strands first base block. After that, plate were washed in order to get rid of fluorescent labels, only nucleotides left. The same passage repeats again and again, until we get whole strand sequence.

 

 

 The NGS gives chance to sequence huge amount of strands at the same time quickly, so it is the indeed technology for sequencing huge organisms genome. However, Sanger sequencing also one of the effective methods, and it can used in sequencing small genes in detail, in order to get accurate data.

Sequencing is key of the life. Since all living organism’s codes written in those sequenced DNA, close investigation of the code will give valuable information about our life. Actually, there millions of actions can be done after we get all organisms’ DNA sequence. As an example, all diseases features can identified, by comparing healthy individual’s DNA with patient. Every individual’s tension to disease can easily identified, lead to prevention from incurable diseases. Moreover, also helps to find correlations between close species, that can lead to find all disappeared animal and plants around the world.

Majority of scientists, after getting more of the organisms DNA sequences, they want to afford way to correct mismatches and mutation in organisms. I support the idea of using codes in order to cure fatal diseases, like cancers. But, what if scientists try to get new animal or organism, which might bring harm to society. If scientists create some genetically modified animal, it will be hard to control it. There is still no guarantee to that corrections in DNA will lead to only positive changes. I am little bit concerned about ethical issues of genomics. Who will have access to these individual’s sequences? What if it used in reproductive decisions, like changing gender of the offspring in the fetus?           

Thereafter, those accomplished DNA sequences of variety organisms can lead to totally diverse world. All limitations of this life might considerably changed or at the same may open up new avenues, which we might be something we have never imagined.

 

References:

http://www.genomenewsnetwork.org/resources/whats_a_genome/Chp2_1.shtml

https://www.thermofisher.com/kr/ko/home/life-science/sequencing/sequencing-education/sanger-next-generation-technology.html

http://hypertextbook.com/facts/1998/StevenChen.shtml    “Length of a Human DNA molecule”(The Physics Factbook, edited by Glenn Elert -- Written by his students)

https://www.youtube.com/watch?v=LSfQPSXQbb4    “The Human Genome Project - Next Generation Sequencing (NGS) Part 1,2,3”

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