Message 91 of 136 (515355)
07-17-2009 12:23 PM
Reply to: Message 89 by traderdrew
07-17-2009 11:54 AM
Re: Sticking to the topic/s, and avoiding deceptions.
|Obviously we are more sophisticated than E. coli. Has any bacteria ever developed cancer?|
...I'm sorry, did you just ask whether a single-celled organism has ever gotten cancer, a disease characterized by unregulated cell replication and almost by definition only happens in multicellular organisms?
How exactly would that happen? That's like asking whether an amoeba has ever gotten heart disease, or whether a virus has ever had an aneurysm!
"Sophistication" depends on how you define the term. Do you mean more vs. less genetic information, as implied by the context of the discussion? Do you mean relative unicellular vs. multicellular life? Size? Adaptability? Behavior patterns? Reproduction methods? Variety of closely related species?
Depending on how you define "sophistication," humans could be the most sophisticated; or the duck-billed platypus could; or the blue whale could; perhaps the giant sequoias; a giant Argentine ant colony that spans 6 continents...
...or even a lowly species of bacteria.
And cell replication does go wrong in bacteria. Sometimes it results in a mutation. Sometimes the child cell simply dies. Relative "complexity" or "sophistication" in an organism doesn't seem to have any bearing on whether that organism is likely to develop a problem like cancer. Mutations, meaning spontaneous genetic differences not directly inherited from a parent organism and usually resulting from a DNA replication error, happen across all life.
In fact, some of the most frequently mutating organisms we know of are viruses and bacteria. HIV, the flu virus, and E. Coli all mutate at incredibly rapid rates, which is why flu vaccines don't always work, and we can't yet cure HIV.
HIV isn't even cellular. It uses RNA instead of DNA, and it mutates at a rate that puts human cells to shame. If your definition of "sophistication" is "susceptibility to copying errors," HIV is one of teh most "sophisticated" things on the planet.
|This message is a reply to:|
| ||Message 89 by traderdrew, posted 07-17-2009 11:54 AM|| ||traderdrew has responded|