When the virus infects a cell, the RNA genome enters the cell and programs it to make new virus particles. These virus particles are released from the cell and go on to infect new cells. In humans, poliovirus is ingested, and replicates in cells of the gastrointestinal tract.Poliovirus, the prototypical picornavirus and causative agent of poliomyelitis, is a nonenveloped virus with a single-stranded RNA genome of positive polarity. The virion consists of an icosahedral protein shell, composed of four capsid proteins (VP1, VP2, VP3, and VP4), which encapsidates the RNA genome (1).RNA viruses generally have very high mutation rates compared to DNA viruses, because viral RNA polymerases lack the proofreading ability of DNA polymerases. The genetic diversity of RNA viruses is one reason why it is difficult to make effective vaccines against them.
"Then each of these strands can be used to create two new copies, and so on, and so on. The cycle of denaturing and synthesizing new DNA is repeated as many as 30 or 40 times, leading to more than one billion exact copies of the original DNA segment."
Answer: Characteristics: The fins are supported by rays, as the name indicates. In contrast to the cartilaginous fish they have a rigid skeleton. The swim bladder is also a unique feature of most ray-finned fish, enabling them to maintain buoyancy as they move up or down in the water.
