There was also a fifth geometric solid the

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correlated with the Four Humors of the Body. There was also a Fifth Geometric Solid -- the Dodecahedron (12 Pentagons) -- which they considered Mysterious (and possibly Dangerous). The Dodecahedron was thought to correlate with a Fifth Element not present on this Planet-- the Quintessence.
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Viruses Page 3 Nucleocapsid • The Combination of Genome and Capsid The Term Nucleocapsid is usually used to describe (1) a completely assembled Virus Particle in the Cytoplasm prior to its Release from the Host Cell as a Virus Particle, (2) an Assemblage of Genome and Capsid in the Cytoplasm prior to its Extrusion through a Host Cell Membrane during which it will obtain an Envelope and become a Virus Particle, or (3) an Assemblage of Genome and Capsid released into the Cytoplasm to infect a Host Cell. Envelope (Some Viruses) • A Host-derived Lipid-Bilayer Membrane that encases the Nucleocapsid - All Negative Sense RNA Viruses are Enveloped The Connection -- if any -- between being a Negative Sense RNA Virus and having an Envelope is Unclear. • The Envelope contains Virus-Coded Proteins Cellular Proteins are usually excluded from a Virus Envelope. - Envelope Proteins can be important for Viral Attachment and Entry into the Host Cell We ʼ ll see that this is particularly true of Influenza Virus Hemagglutinin (H) and HIV Surface Protein (SU). • The Envelope can be integral to Virus Structure Think about a Shrink-Wrapped Case of twenty-four 500 ml Bottles of Spring Water. It is easy and convenient to pick-up this entire Case with one Hand by simply grabbing the Edge of the Shrink-Wrap and lifting it up. The Shrink-Wrap itself isn ʼ t all that Strong, but the entire Shrink-Wrapping provides considerable Rigidity. Remove the Shrink-Wrapping and try to pick-up this same Case of Water Bottles with one Hand. See what I mean? • Enveloped Viruses tend to be very Sensitive to Drying Enveloped Viruses generally have to be transmitted directly from one Person to another Person (Mucous to Mucous) or have to be transmitted within some Body Fluid (Blood or Respiratory Droplets) to maintain the Integrity of the Virus Envelope (and hence the Virus Particle itself). Ancient Texts from the 1940s, 1950s and 1960s sometimes refer to Enveloped Viruses as Ether-Sensitive Viruses. Non-Enveloped Viruses are sometimes called Naked Viruses. Naked Viruses tend to be tough little Beasts. Polio Virus is a Naked Virus. It can withstand several Hours in a Chlorinated Swimming Pool.
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Viruses Page 4 The Baltimore Classification of Viruses The Baltimore Classification is based on how a Virus goes about generating its mRNA. It isn’t nearly as difficult as it appears. Class I and Class II are DNA Viruses (~30% of Animal Viruses are DNA Viruses). Class III, IV, V, and VI are RNA Viruses (~70% of Animal Viruses are RNA Viruses). Some Virologists put Hepatitis B Virus in a separate Class VII; others (like me) don’t.
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