cbirch2
Active Member
- Jul 9, 2011
- 1,394
- 49
- 36
- Thread starter
- #2,461
And i would think anyone truly thought about the spectrum life (and understood its composition) would understand that it is complex but it is just matter none the same.
Think about a person, pretty complicated right? Its Eukaryote, it has complex cells with nuclei. And its multicellular, its cells must act in concert with each other.
Well what about a single yeast cell? Still pretty complicated, but not multicellular. Its still a eukaryote (as is the human), it has a pretty complex set of cellular machinery to do things like glycolysis and protein synthesis. It has membrane bound compartments and its DNA is wrapped into chromosomes and bound in the nucleus. Pretty complex for such a small cell!
How about a simple bacterial cell? Well its much simpler. it doesnt have complex chemical machinery confined in neat compartments like a eukaryotic cell does. It doesnt have a nucleus. its still fairly complicated. It has a cell membrane, but thats the only membrane. Its DNA is a free floating ring floating within the cells cytoplasm. All of the cells reactions take place in the cytoplasm. Its magnitudes simpler than a eukaryote, but still could be considered very complex.
How about a virus? No metabolism, no organelles. Its just a genome, and a protein capsid surrounding the genome. The capsid is just a repeated sequence of capsomeres, which are coded for by the genome they surround, and are created with the replication of the genome during infection and replication. So a virus is simply as complicated as its genome. A virus is fairly simple. Maybe you would call it complex, but i wouldnt.
What about a viroid? If a virus is simple, a viroid must be simpler. It doesnt have the complex niceties like a protein coat or spikes. Its just a strand of DNA that causes problems when its inside other cells.
So a viroid is just DNA. Is DNA that complex? No, its just nucleotides. Nucleotides are just carbon, with some functional groups like carboxyl attached.
Where do you draw the line? Where does life start, and where does life end?
Which part of life isnt ultimately controlled by biochemistry?
Think about a person, pretty complicated right? Its Eukaryote, it has complex cells with nuclei. And its multicellular, its cells must act in concert with each other.
![200905021SUM12.jpg](/proxy.php?image=http%3A%2F%2Feshowcase.unimelb.edu.au%2Ffiles%2Fshowcase%2F200905021SUM12.jpg&hash=87034e485889d7eba709fe5bb0c1c580)
Well what about a single yeast cell? Still pretty complicated, but not multicellular. Its still a eukaryote (as is the human), it has a pretty complex set of cellular machinery to do things like glycolysis and protein synthesis. It has membrane bound compartments and its DNA is wrapped into chromosomes and bound in the nucleus. Pretty complex for such a small cell!
![Image28.jpg](/proxy.php?image=http%3A%2F%2Fwww.etap.org%2Fdemo%2Fgrade7_science%2FImage28.jpg&hash=b969ceef2b080e74d5c66adcff60268a)
How about a simple bacterial cell? Well its much simpler. it doesnt have complex chemical machinery confined in neat compartments like a eukaryotic cell does. It doesnt have a nucleus. its still fairly complicated. It has a cell membrane, but thats the only membrane. Its DNA is a free floating ring floating within the cells cytoplasm. All of the cells reactions take place in the cytoplasm. Its magnitudes simpler than a eukaryote, but still could be considered very complex.
![300px-Average_prokaryote_cell-_en.svg.png](/proxy.php?image=http%3A%2F%2Fupload.wikimedia.org%2Fwikipedia%2Fcommons%2Fthumb%2F5%2F5a%2FAverage_prokaryote_cell-_en.svg%2F300px-Average_prokaryote_cell-_en.svg.png&hash=4249b803f73582962c1c8007f48eab45)
How about a virus? No metabolism, no organelles. Its just a genome, and a protein capsid surrounding the genome. The capsid is just a repeated sequence of capsomeres, which are coded for by the genome they surround, and are created with the replication of the genome during infection and replication. So a virus is simply as complicated as its genome. A virus is fairly simple. Maybe you would call it complex, but i wouldnt.
![int6.jpg](/proxy.php?image=http%3A%2F%2Fpathmicro.med.sc.edu%2Fint6.jpg&hash=1ff26974efc893a7c378b3e47afb76e3)
What about a viroid? If a virus is simple, a viroid must be simpler. It doesnt have the complex niceties like a protein coat or spikes. Its just a strand of DNA that causes problems when its inside other cells.
![Viroid4.jpg](/proxy.php?image=http%3A%2F%2Fwww.emergentcomputation.com%2FImages%2FViroid4.jpg&hash=6d793df4d675eb6b3bfd4ef03c76ea7c)
So a viroid is just DNA. Is DNA that complex? No, its just nucleotides. Nucleotides are just carbon, with some functional groups like carboxyl attached.
![Nucleotides_syn3.png](/proxy.php?image=http%3A%2F%2Fupload.wikimedia.org%2Fwikipedia%2Fcommons%2F2%2F2d%2FNucleotides_syn3.png&hash=c94811aa9de10c28ddcce7174c67ddec)
Where do you draw the line? Where does life start, and where does life end?
Which part of life isnt ultimately controlled by biochemistry?