Question

Identify the organism with the following characteristics.
I. Simpler than viruses.
II. Genetic material is ssRNA.
III. Can cause plant diseases.
IV. Requires a host for multiplication.

• A. Virions
• B. Viroids
• C. Prions
• D. Mycoplasma

Answer 1

The correct option is B Viroids

Viroids are highly infectious particles which are made up of only the genetic material. They are known to cause diseases such as the potato spindle.

Virions are the complete virus particles with the genetic material, protein coat and envelope, if any. These represent the extracellular forms of virus. Upon successfully finding a suitable host cell, these virions may inject their genetic material into the cells which get integrated in host genome and directs it to form more of themselves. The fully formed new particles can again be called as virions and can infect new host cells.

Prions are highly infectious particles formed only of proteins. It causes many neurodegenerative diseases in animals.

Commonly called as the "Jokers of the plant kingdom", Mycoplasma lack cell wall. They are pleiomorphic and are known to be parasitic to animals and plants.