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Let's start a discussion with the dna.
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Dna, the full form of dna is deoxyribonuclic acid because it is one of the type of nucleic acid.
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Other type of nucleic acid is rna.
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This dna, that is deoxyribonuclic acid, it acts as genetic material in most of the organisms or cells except viruses.
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This dna molecule, it condenses to form chromosomes.
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These chromosomes, these are rod -like structures.
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For example, this.
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These chromosomes, after duplication or we can say replication, they will appear like x -shaped.
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These two parts of the chromosome, these are called sister.
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Chromatids and sister chromatids these are chromosomes which are attached to each other at the point called centromere and this type of chromosome with two sister chromatids it is called duplicated chromosome.
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Hence, if we have, for example, four duplicated chromosomes, then we can say that it will contain eight chromosomes because single duplicated chromosome, it contained two sister chromatids, which are chromosome arms attached to each other at the centromere.
02:08
This duplication of chromosomes that forms it double the amount of chromosomes it is done by the process called dna replication dna replication it occurs during the s phase of the cell cycle and it involves the enzymes called dna polymerases or just dna polymerase in prokaryotes there are 5 dna polymerases dna polymer is 1 dna polymer is 2 dna polymer is 3 dna polymer is 4 and dna polymer is 5 these dna polymerises in pro -carriers they perform the function of dla replication repair and they stop or we can say repair the mutations hence in absence of these enzymes replication of dna will stop also so, there will be mutations that will be present in the dna in absence of these enzymes because they function as proofreading enzymes...