The animal viruses usually attack vertebrates like man, fowl, pigeon, dog, cow, etc. they cause serious diseases. However, some animal viruses attack arthropods but produce little or no ill effects. They vary in shape and size and may contain DNA or RNA.Complete answer:
Poliovirus is the causative agent of Poliomyelitis and is a human enterovirus.
The poliovirus is small, about 30μm in diameter, and contains about 75% protein and 25% RNA.
Polio viruses are single-stranded RNA viruses belonging to the family of Piconaviridae.
They have naked protein capsid with a dense central core.
The genomic RNA is approximately 7440 to 7500 nucleotides in length.So the correct answer is option A. RNAAdditional information:
some other important viral diseases are
(i) Influenza- the virus is rounded or oval in shape, contains RNA in an inner helical core of ribonucleoprotein surrounded by mucoprotein.
(ii) Rabies – the virus is bullet-shaped, about 75mμ wide and 180mμ long, and contains RNA. It causes a fatal disease called hydrophobia.
(iii) Adenoviruses – cause human respiratory diseases. The virus contains double-stranded DNA associated with protein and enclosed within the capsid.
(iv) Herpes- a viral disease characterized by vesicular eruptions on the skin and mucosa together with damage to various organs and systems.Note:
Both RNA and DNA cannot be genetic material at the same time
Poliovirus is transmitted primarily by the fecal-oral route and replicates in the pharynx and lower intestinal tract.