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Title: Homework Problem! Post by: barry on Aug 15, 2010 This is for my developmental biology class...
Fugu is a vertebrate like humans, with many of the same complex structures and organ systems. However, unlike humans the size of the Fugu genome is a mere 400 Mb compared to the 3000 Mb of humans. What are two likely explanations for this difference? What does this say about genome size? How do I go about answering this question :-X PS. Isn't this from a Simpsons episode? Title: Re: Homework Problem! Post by: duddy on Aug 15, 2010 Hey, welcome to the forum!
This question is a typical developmental biology question asked to undergrads... Remember that the difference of genome size is due almost entirely to a reduction, not in the numbers, but in the sizes of the introns, and the sizes of the regions of noncoding DNA that lie between genes. So it is likely that this species has managed to rid itself of most of the noncoding DNA (the introns)... Title: Re: Homework Problem! Post by: bio_man on Aug 18, 2010 PS. Isn't this from a Simpsons episode? yep it's when homer gets poisoned :P Title: Re: Homework Problem! Post by: ThePsychic on Aug 20, 2010 Yeh so, somehow Fugu has either managed to rid itself of most of the noncoding DNA that clutters the genome of species such as humans (Junk DNA), or has managed to avoid accumulating this DNA in the first place due to less selective pressure in a stable habitat. The reason the two species share similar structures is because of conserved exons and conserved segments of regulatory DNA. Overall, genome size does not necessarily imply that the organism is more or less complex since the bulk of our junk DNA is actually junk.
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