What Is C-value Paradox?
C-value refers to the total amount of DNA in the genome. We would expect that the more complex the organism, the more DNA is needed to run it. Therefore, we would expect a linear relationship between genome size and organism complexity. The idea appears to make sense -- the more complex the organism is, the more genetic information it needs (i.e., larger C-value).
In smaller organisms such as viruses and bacteria, there is no room for excess DNA (smaller C-value). At the lower range of complexity, this holds - Bacteria have smaller genomes than eukaryotes and viruses have smaller genome than bacteria.
In larger organisms, this relationship breaks down. Organisms have DNA apparently i excess of what is needed; repetitive sequences, JUNK DNA. This is called the C-value paradox that is in most complex organisms, there doesn't appear to the expected relationship between complexity and genome size.
In smaller organisms such as viruses and bacteria, there is no room for excess DNA (smaller C-value). At the lower range of complexity, this holds - Bacteria have smaller genomes than eukaryotes and viruses have smaller genome than bacteria.
In larger organisms, this relationship breaks down. Organisms have DNA apparently i excess of what is needed; repetitive sequences, JUNK DNA. This is called the C-value paradox that is in most complex organisms, there doesn't appear to the expected relationship between complexity and genome size.
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