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Monday, February 17, 2020

Virology

Introduction
They may be the oldest organisms on earth!!!  They have their own morphology and there are several different types viruses.  They infect different types of organisms.  There are many different species of viruses.  There is a long history is virology. 
Evolution
Viruses may have started off as small cells that were parasites.  Over time they may have lost many genes that wasn't involved in parasitism.  There @ least 2 bacteria that are like viruses, which makes this idea seem true.

Some virologists believe viruses where genetic material that was ejected from cells.  Transposons are DNA that can move around in the chromosome.  They may be the ancestor of viruses.   Plasmids may be there ancestors as well.

Some believe viruses evolved at the same time as cells.  Some viruses need other viruses to get a protein coat.  Viroids are parasitic RNA that infects plants.  It is even smaller than viruses!!!  Some people think viruses existed b4 cells!

Viruses are the fastest evolving organisms.  This is because they are the simplest life forms.  Sometimes 2 or more viruses infect a cell and swap genes.  Influenza evolve every year.         
Morphology
Viruses have 5 shapes: 
  1. "Helical – These viruses are composed of a single type of capsomer stacked around a central axis to form a helical structure, which may have a central cavity, or hollow tube.
  2. Icosahedral – Most animal viruses are icosahedral or near-spherical with icosahedral symmetry.
  3. Prolate – This is an isosahedron elongated along one axis and is a common arrangement of the heads of bacteriophages.
  4. Envelope – Some species of virus envelope themselves in a modified form of one of the cell membranes, either the outer membrane surrounding an infected host cell or internal membranes such as nuclear membrane or endoplasmic reticulum, thus gaining an outer lipid bilayer known as a viral envelope.
  5. Complex – These viruses possess a capsid that is neither purely helical nor purely icosahedral, and that may possess extra structures such as protein tails or a complex outer wall."
Types 
There 2 kinds of viruses: some have DNA, others have RNA.  Some are single stranded, some are double stranded.  Some of viruses are positive others are negative.

DNA viruses: They are larger than RNA and have a lot of diversity.  They tend to be double stranded.  They replicate in the nucleus.  The viral DNA is injected to the cell DNA.  Single stranded DNA virus become double stranded after they invade a cell.   
RNA viruses: They are mostly single stranded.  They replicate in the cytoplasm.  They mutate faster than DNA viruses, because it has less genetic material.
Positive viruses get help from the host cell ribosomes to make protein.  Negative viruses don't get help from the host cells ribosomes. 
List of Viruses
Ebola: It's a virus that attack different cells in the body.  It causes a person organs to melt.  It may have been genetically engineered in Zimbabwe.
HIV: It attacks Killer T cells, so the person gets more infections.  They are sick more often.  A person with HIV can live a full life as long has it doesn't turn to AIDS.  HIV was created in laboratory.  It is a combination of the Visna and Bovine viruses.  Look up MKNAOMI.  It was created to get rid of Africans.  It was put in vaccines that were given given to people in Africa.  It was also given to homosexual men in the U.S. through a Hepatitis B vaccines.  Look up Dr. Stecker, he knows a lot about this virus.
Rabies: It's a retrovirus carried by dogs and other mammals.  If a human is infected and don't get treatment they will die.  Bats in every continental state carry rabies.  It may take 5 years 4 symptoms to develop.  It causes flu like symptoms and make you crazy as hell!!!!!  We must kill all dogs and bats to get rid of rabies.
TMV: It's a RNA virus that infects tobacco and many other plants.  It infects over 100 plants and makes their leaves ugly.   
Sputnik: They infect a certain type of virus that infect amoebas.
Coronavirus: It's a retrovirus that infects birds and mammals.  The ancestor of this virus lived 10,000 years ago.  It causes colds in humans.  There was an outbreak of this viruses in China recently and now it's all over the world!!!!!!  The Russians believe this outbreak was caused by the U.S. government.  I not sure who caused it, but somebody did.  This form of coronavirus was genetically engineered.   

There are many other viruses, but this will suffice.       

 Organism Infection
Viruses that infect viruses are called bacteriophages.  Lytic cycle is when a bunch viruses are created in bacteria and then the bacteria explodes receiving them.  Lysogenic cycle is when a virus genome becomes a part of a bacteria's DNA.  They have anywhere from 4-100s of genes.  All archaeal viruses so far discovered have DNA instead of RNA, expect for one.  Viruses that infect archaea very different from bacteriophages.  Viruses that infect protists are huge!!!!  Most mycovirus have double stranded RNA.  They may be the parents of plant viruses.  Most plant viruses are single stranded RNA viruses.  They are spread by insects, sap, nematodes, seeds, pollen, etc.  Viruses causes a lot of diseases in animals and sometimes they cross the germline and become apart of our DNA.  Viruses that infect other viruses are called virophages. 
History of Virology
Vaccines were created in China millenia ago and a African man saved European people lives in Boston by giving them a smallpox vaccine.  A European woman seen a vaccine in Turkey and brought it to England.  A Russian biologist discovered TMV.  Many other European scientists discovered a lot about viruses. 

Conclusion
Viruses are very old organisms.  Maybe the oldest.  They come in 5 different shapes.  They have RNA or DNA, single or double stranded, and they are positive or negative.  There are many famous viruses.  They infect every type organism, even each other.  Virology been around for centuries if not longer. 

References
https://en.wikipedia.org/wiki/Virology 
https://www.ncbi.nlm.nih.gov/books/NBK21523/
https://www.ncbi.nlm.nih.gov/books/NBK8098/
https://en.wikipedia.org/wiki/Virus
https://courses.lumenlearning.com/boundless-microbiology/chapter/structure-of-viruses/
https://www.atsu.edu/faculty/chamberlain/website/tritzmed/LECTS/PROPERT.HTM
http://www.differencebetween.net/science/health/difference-between-dna-and-rna-viruses/
https://www.khanacademy.org/science/biology/biology-of-viruses/virus-biology/a/evolution-of-viruses
https://www.mr.mpg.de/13934518/viruses-of-protists
https://en.wikipedia.org/wiki/Mycovirus
https://www.hindawi.com/journals/archaea/2013/251245/#supplementary-materials
https://www.khanacademy.org/science/biology/biology-of-viruses/virus-biology/
https://en.wikipedia.org/wiki/Plant_virus
https://streckermemorandum.com/
https://www.medicalnewstoday.com/articles/181980#symptoms
https://en.wikipedia.org/wiki/Sputnik_virophage