I’m trying to understand viruses, but no sooner do I figure out one thing than they discover some new aspect. For instance, I had learned about the four nucleic acids, than it turns out that RNA (single strand nucleic acids) has a different fourth nucleic acid than DNA (double strand nucleic acids).
“Nucleic acids are the biopolymers, or small biomolecules, essential to all known forms of life. The term nucleic acid is the overall name for DNA and RNA. They are composed of nucleotides, which are the monomers made of three components: a 5-carbon sugar, a phosphate group and a nitrogenous base. If the sugar is a compound ribose, the polymer is RNA (ribonucleic acid); if the sugar is derived from ribose as deoxyribose, the polymer is DNA (deoxyribonucleic acid).Nucleic acids are the most important of all biomolecules. “ (Britannic instead of Wikipedia)
Pictures here. I’ve always thought of viruses as little flecks hardly big enough to have “structure” but I could not have been more wrong. They are zoomorphic, inventive, invasive attempts at life that went wrong, or maybe primitive life that couldn’t quite get it together. Or maybe they’re jokes or caught in transit, merely becoming instead of being. The scientists have a sense of humor about it. The very largest ones are called “Mimiviruses” or “Pandoraviruses.” I imagine Mimi and Pandora were not amused.
These non-creatures were not created -- they just formed themselves. This raises questions about creation, a word that implies that some greater force "made" creatures like humans. But that's silly, since it's clear that it was simply time that clustered elements together, evidently by accident, so that viruses emerged. Does everything emerge from particles clumping? It seems ignominious but also true. The only creator is Time.
"Strings of nucleotides are bonded to form helical backbones—typically, one for RNA, two for DNA—and assembled into chains of base-pairs selected from the five primary, or canonical, nucleobases, which are: adenine, cytosine, guanine, thymine, and uracil. Thymine occurs only in DNA and uracil only in RNA. Using amino acids and the process known as protein synthesis, the specific sequencing in DNA of these nucleobase-pairs enables storing and transmitting coded instructions as genes. In RNA, base-pair sequencing provides for manufacturing new proteins that determine the frames and parts and most chemical processes of all life forms."
But that raises another question: Can humans create? Or is Time merely acting through us to "create" the illusion of our making? If we are neither created nor able to create -- just transmit -- then are we simply transient accidents? Sometimes the idea is comforting.
So I'm going along, hanging on tight, until I come to the protists. I already knew about rickettsia, which are tiny bacteria: "Rickettsia is a genus of nonmotile, Gram-negative, nonspore-forming, highly pleomorphic bacteria that may occur in the forms of cocci, bacilli, or threads." "A protist is any eukaryotic organism that is not an animal, plant, or fungus. The protists do not form a natural group, or clade, since they exclude certain eukaryotes with whom they share a common ancestor i.e. some protists are more closely related to plants or animals than they are to other protists."() In other words, rickettsia were mistaken for viruses once.
Protists are the junk category of all this teeny cell stuff. "Protists make up a large portion of the biomass in both marine and terrestrial environments. Other protists include pathogenic species, such as the kinetoplastid Trypanosoma brucei, which causes sleeping sickness, and species of the apicomplexan Plasmodium, which cause malaria."
When I was an animal control officer, we were told never to give blood because we were likely to be carrying all these possibly destructive bits and no one had time to test for them, even if there WERE a test for them. In fact, it was not an officer who become ill, but the husband of Renee. She said it was a rickettsia and she reshingled the roof on their house herself, because he was too weak to do it as intended. We are indeed emergent from the chaos of interacting cells -- whether alive, nonnative, and undecided. Gather ye rosebuds while ye may.
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