Recently we have all heard so much about the flu virus and the new and scary “Covid 19” virus. But what are these infectious “bugs” that cause the common cold and other diseases and so much disruption? So what is a virus?
You all (almost all of you) will remember that each animal and plant cell has a nucleus (like a nut) embedded in “cell jelly” (protoplasm). Each cell is surrounded by a thin membrane to keep things together and protect it. You also have heard of DNA— the long chain complex molecule— that encodes and defines each cell and is found in the nucleus of every animals and plant ell. DNA is packed tightly into the nucleus (the word means “nut’) which is located in the interior of the jelly filled cell.
DNA stores the master “code” (hereditary material) that controls duplication of the the cell and determines what that cell will look like and what it will do. DNA acts like the maestro at the head of an orchestra. Imagine the orchestra as a single big cell. DNA in the nucleus operates to conduct the “music” of the cell. Like an orchestra leader, it indicates to the various cell components —in our orchestra analogy: such as the brass or string sections—what to play and when to play it—and how loud or soft. All living things are made up of cells and must have DNA to control them.
Bacteria are very simple plants. These single celld primitive organisms are composed of a rigid outer cell coating made up of sugars and amino acids and an inner cell membrane, but no nucleus. Their DNA—the master cell control center (or “orchestra leader”) is dispersed throughout the cell jelly and not confined into a little “nut”.
Viruses are an even simpler and unique to class of “organism”. They have no “cell”, no cell “jelly”, or cell membrane. They are composed of only a strand or two of the “orchestra leader” the encoding molecule which is surrounded by a protein or lipid (fatty) sheath. Some have DNA (it has two strands) others have RNA ( only a single strand). Thus a virus is an “orchestra leader” with no orchestra to lead. The virus survives by entering a cell and taking it over. Viruses have evolved to attack many different animals and plants. There are some viruses that attack only bacteria. “New” viruses are often those which have simply switched from one host animal to another...like the coronavirus—which some believe was originally adapted to attack the Pangolin—or others claim it was a bat virus.
If these virus “bugs” are indeed “living” they are reduced to the simplest possible form—only a strand of DNA or RNA which can control a cell-if it had one. A virus might be analogous to a conductor without an orchestra. just waiting for the opportunity to take over a group of musicians to conduct.
No one knows for sure how these virus entities evolved. Did they just “slim down” as a result of evolutionary adaptation from a former tiny cellular organism? Or are they the holdovers from the earliest stages of life—the primordial organism from which all other life evolved? I suspect it must have been the former—since they seem to have adapted to attack more complex cells. Thus they must have come on the scene later on—after more complex cells had evolved.
Since viruses are composed of only a few strands of nuclear material, they must be, indeed very very small. They are much smaller than a cell or the nucleus of most cells. (Imagine an average hen’s egg as a typical human cell. The size of a virus relative to that human “cell” would be smaller than a poppy seed (in fact, about 1/4 the size of an average poppy seed)
The virus’ survival plan is correspondingly simple as well . They must enter a host cell and take over that cell to survive and reproduce (replicate) new copies of themselves inside the cell. They have evolved various strategies to get close to living cells in a l organism like a plant or animal) and then somehow squeeze their way through the host cell’s protective cell membrane and enter into the cell “jelly”. Once Inside, they take control over that cell. In fact they destroy that cell’s own DNA and substitute their nuclear material. Inside the cell they use the substance of cell jelly and other parts to reproduce their own nuclear material, finally destroying the host’s cells and converting its substance into copies of itself. These break out and spread far and wide to infect other cells. It is assumed that these “beak out” cells are the one that are found in the mucus and other body fluids of the host.. By destroying so many host cells to covert them into virus entities is not good for the host. The host begins to feel sick when it’s lung,liver, or kidney cells are being destroyed to become a bunch of virus units.
Imagine the band leader of a Hard Rock Band—like “Metallica”— as if he (or she) was a virus. The Metallica band leader wanders around the music world alone with no band to lead. At some point it encounters an orchestra playing within a philharmonic theater—and sneaks its way inside where a full symphony orchestra is performing Beethoven’s 5th Symphony. Pushing aside the tuxedo-clad maestro at the rostrum, the Metallica (virus) band leader rips the baton from the maestro’s hand and pushes him off the rostrum. Then he begins directing the now confused members of the orchestra’s strings, woodwinds, brass and percussion sections into playing a cacophony of awful dissonance. Finally, in full control and with the players responding to commands—the orchestra begin to play “Rock a Billy” in a “Metallica style.
As that “music” takes hold each of the orchestra members begins to turn magically into a physical a copy of the Metallica band leader. As this change progresses the sounds from the instruments fades and stops—when all the instruments and musicians have turned into clones of the Metallica band leader. These newly formed band leaders —now race out of the theater to spread out in a frantic search to find a new symphony orchestra to take over. Ugh!
In the human body a virus may enter your nasal cavity and enter the membrane of an epithelial cell. It makes these cells work extra hard producing secretions that make your nose drip. You get the sniffles and sneezes. These outpourings of fluid are populated with the new viruses. They can give you a runny nose and make you sneeze or cough. Sneezing and coughing are the means viruses use to help disperse the virus copies it has made in the cells it has taken over. When a person sneezes the fluid droplets enter the air and are light enough to remain suspended for some time. If you are close enough—within 6-10 feet— you may breathe in these droplets. That is what the virus’ life plan mostly depends on. Getting one host to sneeze and another host near-by to inhale its newly created virus copies. The fact that humans like to be close together is part of the virus’ evolutionary plan. It depends on this for survival.
In very dry air —like cold winter air that has been drawn in from the outside and then been heated, like in a warm house air, a. movie theater or school room—these liquid droplets begin to evaporate fluid our of the drop and into the air. Under these circumstances the drop loses moisture to the air and decreases in size as evaporation continues. But as a smaller droplet, it has less and less attraction to the earth due to the laws of gravity. Also as a very tiny particle it can stay lofted for very long periods of time. Even tiny air currents like someone’s hand moving through the air can loft it up higher. So in dry interior air especially in winter the droplets can become very very small and thus remain lofted for very long periods. This makes them even more dangerous in winter and in enclosed places. These very small drops (aerosols) can be breathed in an may then be drawn far down into human lungs where they may cause more severe forms of the flu like disease.
But even if no new host inhales the infected droplets —the virus has a back up plan too. Eventually, some of these floating droplets will settle out of the air like dust or pollen to form an invisible film. They will adhere to surfaces like tables, chairs, desks, clothes and even the floor They can remain infective on surfaces for log periods of time...hours on some surfaces days on others. If you touch these places, then put your hand to your eyes, your nose, or you mouth you can self-infect. The virus seems to have evolved in such a way as to take advantage of the fact that humans have a natural habit of touching their face—nose, eyes and mouth—sometimes several times a minute. The virus depends on that habit to move itself right into the very places it prefers—the mucus membranes of the eyes, mouth and nose.
One thing more. The fatty coating on the exterior of the virus which protects the nuclear material inside is subject to the action of soap—just like grease stains on your hands. That is why thorough hand washing with foamy soap and warm water is so effective. The soap molecule has the ability to attach itself to both water and oil or fats. One end of its molecule attaches to the fatty covering on the virus and the other end continues to adhere to the other water molecules—the result is that the soap action tends to pull this outer coating of the virus apart. It breaks up the outer coating and carries it away with the soap bubbles. That exposes the interior nuclear materials to the soap, water, bases and acids of the external environment which denatures them—renders them no longer viable.
So I hope that this helps you to understand something about viruses—as well as the importance of avoiding infection. Avoid places where people are coughing or sneezing. Stay out of crowds, stop touching your face and mouth and wash your hands regularly.
Got the idea?
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