Hi friends!
How many of us know about DNA? I believe most of us know about it. But still, if there is anyone out there who doesn't know about it or would like to know more about it, this post be useful. The knowledge about DNA is important at this point of time. Because, our next post is going to talk about the most important topic based on the DNA. It is going to be so much important that it is going to show us apparently the path of our history - The ultimate goal of this blog!
DNA stands for DeOxyRibo Nucleic Acid. It is the acid that contains genetic information of a living being. There is only one group of organisms in the world that doesn't have DNA - RNA Virus. Apart from this, all the living organisms have got DNA. It is present in a cell. Within cell, it is seen in two regions, one being called 'Nucleus' and the other being called 'Mitochondria'. Based on this, we could classify the DNA into two types - nDNA (found in nucleus) and mtDNA (Mitochondrial DNA).
There are many information to know about DNA. But, they are out of scope of this blog, the inclusion of which will make this blog a Science blog rather than a History blog. So, we shall stand within our bounds. Also, we shall restrict ourselves to human DNA as that is what is needed.
nDNA:
Human nDNA contains 46 chromosomes out of which 23 come from the biological father and 23 come from biological mother. These 46 chromosomes are responsible for various charateristics and behaviours of a human. Out of the 46, 2 chromosomes are responsible in determining the sex of a human. They are called Xand Y chromosomes. A human female contains 2 chromosomes(XX) for sex determination and a human male contains 2 chromosomes(XY) for sex determination. During reproduction, a male will contribute a sex chromosome (Could be X or Y since he has got XY) and a female will contribute a sex chromosome (could be only X since she has got XX). If the male
contributes X, then the child will have X from father and X from mother making it to have XX to become a female child. If father contributes Y, then the child will have Y from father and X from mother making it to have XY to become a male child. And all of these 46 chromosomes during reproduction (cell division) will mix and fuse and can result in any combination. This is the story and significance of nDNA.
mtDNA:
Against the 46 chromosomes present in an nDNA, there is only one chromosome present in mtDNA. The most important feature of this DNA is that it is inherited only through mother. i.e. Both male and female will possess this but only the female will pass on this mtDNA to the child. e.g. a couple have got 2 male children. It means that the mother would have passed mtDNA to her 2 male children. But, neither of the 2 male children will pass on this mtDNA to their children.
Mutation:
Mutations are the accidental changes that happen to the DNA. e.g. A is a DNA. A small change of a may happen to it to make it Aa and a change of b may happen to it to make it Ab and so on. So, the DNA 'A' becomes the ancestor DNA for DNAs like Aa, Ab.
Haplogroup:
It is a group of people who share a specific mutation or mutation series that link them to the common ancestor. So, consider that we find a DNA with a Y chromosome with mutation (change) y. If we remove the change (mutation) y, we would get the details of the original DNA with Y chromosome. In some cases like this,it is a single change to be removed. But in many cases, there will series of changes to be removed to get the original one.
As in our previous example under 'Mutation', the DNA with chromosome called A becomes the ancestor and all the other mutated ones like Aa, Ab form a haplogroup. Our world population has got many such haplogroups which would map to a common ancestor. This is the whole root that we have to understand before we move on to the next post.
I am not posting the actual study in this post to allow the viewers to have some time understand the basics of the DNA and all the stuff explained here, to make their own study by googling or any such way to make themselves stand in a better position in this subject before going through the actual study that is going to follow this.
...THE PATH WILL BE FOLLOWED...
How many of us know about DNA? I believe most of us know about it. But still, if there is anyone out there who doesn't know about it or would like to know more about it, this post be useful. The knowledge about DNA is important at this point of time. Because, our next post is going to talk about the most important topic based on the DNA. It is going to be so much important that it is going to show us apparently the path of our history - The ultimate goal of this blog!
DNA stands for DeOxyRibo Nucleic Acid. It is the acid that contains genetic information of a living being. There is only one group of organisms in the world that doesn't have DNA - RNA Virus. Apart from this, all the living organisms have got DNA. It is present in a cell. Within cell, it is seen in two regions, one being called 'Nucleus' and the other being called 'Mitochondria'. Based on this, we could classify the DNA into two types - nDNA (found in nucleus) and mtDNA (Mitochondrial DNA).
There are many information to know about DNA. But, they are out of scope of this blog, the inclusion of which will make this blog a Science blog rather than a History blog. So, we shall stand within our bounds. Also, we shall restrict ourselves to human DNA as that is what is needed.
nDNA:
Human nDNA contains 46 chromosomes out of which 23 come from the biological father and 23 come from biological mother. These 46 chromosomes are responsible for various charateristics and behaviours of a human. Out of the 46, 2 chromosomes are responsible in determining the sex of a human. They are called Xand Y chromosomes. A human female contains 2 chromosomes(XX) for sex determination and a human male contains 2 chromosomes(XY) for sex determination. During reproduction, a male will contribute a sex chromosome (Could be X or Y since he has got XY) and a female will contribute a sex chromosome (could be only X since she has got XX). If the male
contributes X, then the child will have X from father and X from mother making it to have XX to become a female child. If father contributes Y, then the child will have Y from father and X from mother making it to have XY to become a male child. And all of these 46 chromosomes during reproduction (cell division) will mix and fuse and can result in any combination. This is the story and significance of nDNA.
mtDNA:
Against the 46 chromosomes present in an nDNA, there is only one chromosome present in mtDNA. The most important feature of this DNA is that it is inherited only through mother. i.e. Both male and female will possess this but only the female will pass on this mtDNA to the child. e.g. a couple have got 2 male children. It means that the mother would have passed mtDNA to her 2 male children. But, neither of the 2 male children will pass on this mtDNA to their children.
Mutation:
Mutations are the accidental changes that happen to the DNA. e.g. A is a DNA. A small change of a may happen to it to make it Aa and a change of b may happen to it to make it Ab and so on. So, the DNA 'A' becomes the ancestor DNA for DNAs like Aa, Ab.
Haplogroup:
It is a group of people who share a specific mutation or mutation series that link them to the common ancestor. So, consider that we find a DNA with a Y chromosome with mutation (change) y. If we remove the change (mutation) y, we would get the details of the original DNA with Y chromosome. In some cases like this,it is a single change to be removed. But in many cases, there will series of changes to be removed to get the original one.
As in our previous example under 'Mutation', the DNA with chromosome called A becomes the ancestor and all the other mutated ones like Aa, Ab form a haplogroup. Our world population has got many such haplogroups which would map to a common ancestor. This is the whole root that we have to understand before we move on to the next post.
I am not posting the actual study in this post to allow the viewers to have some time understand the basics of the DNA and all the stuff explained here, to make their own study by googling or any such way to make themselves stand in a better position in this subject before going through the actual study that is going to follow this.
...THE PATH WILL BE FOLLOWED...
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