The Homo Sapien genome is a highly interwoven tapestry of historical and conserved DNA sequences that run a wide gamut of functionality. When undergoing replication, these genes are grouped into chromosome bundles that can be made visible with high power electron microscopes. The categorization of each chromosome bundle visually is useful in study to determine the roles of each chromosome.
All of the chromosomes contain repeated instruction sets. There are several possible reasons for why this phenomenon exists: sequences perform the same function across the cell, sequences are copied many times to ensure redundancy in highly volatile regions, or, interestingly enough, sequences are the byproduct of countless intra-cellular incursions by other cells, such as bacteria and even viruses.
Chromosome I, for instance, is responsible for regulating the extra-cellular membrane matrix. Others, such as Chromosome III, maintain energy output from mitochondrial energy centers. Chromosome II and IX handle the creation and destruction of ubiquitin, which handles the recycling of all protein within the cell. Many of the requirements for these processes overlap, and one can expect and does see similar sequences performing similar functions across chromosomes.
All of these operations require various levels of redundancy to ensure they are not lost due to replication error or accidental degradation. The size of each chromosome can provide a clue as to their individual function and significance.
This illustration highlights the relative size of each chromosome in the Homo Sapien genome.
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