4 of 14

Write now Article Tools

A virus is a very simple structure. Basically, it is a strand of RNA or DNA surrounded by a coat of proteins, which is, in turn, surrounded by a phospholipid membrane. RNA is short for ribonucleic acid, while DNA is short for a similar molecule named deoxyribonucleic acid. To understand the anatomy of a virus, one must understand the unique properties of ribonucleic acids.

For life to evolve on earth, there had to be a period of chemical 'evolution' first. Atoms are not alive in the strict sense of the word but there are things that atoms can and will do because of their atomic structures. Briefly, atoms with full outer electron rings are inert or inactive, while atoms with incomplete outer electron rings actively join with other atoms in order to complete those outer rings. Some atoms only need one or two more electrons to fill their outer shell, while others can get rid of one or two electrons and drop back down to the next complete inner ring. Atoms that get rid of electrons are called donors, while atoms that take electrons are called acceptors.

This means that atoms do not stay separate and alone. They join together to form compounds. Water, for instance, is formed by one oxygen and two hydrogen atoms, where oxygen acquires the use of two hydrogen electrons to fill oxygen's outer orbit. Hydrogen donates its electron because then it has no electron orbit at all. Water is important because it is the one compound necessary for life as we know it to exist. Life evolved in the warm turbulent waters of the early ocean because molecules did not stop at forming simple compounds. Instead, in the conditions experienced by the earth 4 billion years ago, molecules combined and joined into huge molecules; what we now call organic acids: nucleic acids, fatty acids and amino acids.

Only seven or so kinds of atoms are necessary for life. Life needs only carbon, hydrogen, oxygen and nitrogen to form its basic building blocks: carbohydrates, proteins, fats and nucleic acids. First the basic building blocks of these molecules formed: simple sugars and carbohydrates, fatty acids, amino acids, and lastly and most importantly for life, the nucleic acids.

The nucleic acids are the key to both Life as we know it and those curious, parasitic, half-alive viruses that us show what must have happened billions of years ago. Only one molecule, ribonucleic acid, can self-replicate. This molecule alone of all the molecules in the oceanic soup, could split apart like a zipper and

• 1
• 2
• next page >>

Add your voice

Know something about The anatomy of a virus?
We want to hear your view. Write now!