Question

A characteristic of viruses is
A. Without independent metabolism.
B. With independent metabolism.
C. Multiplication outside living cells.
D. Culture in the cell-free medium.

Answer 1

One should first know about a virus and its characteristics in order to answer this question. A virus is a microscopic infectious agent that replicates only inside the living cells of an organism. Viruses infect all types of forms, from animals and plants to microorganisms.

Complete answer: For an organism to ensure its survivability, it needs to perform vital functions. In the case of viruses, they depend on the host they live upon for metabolism. A virus is an infective agent which has the ability to multiply only within the living cells of a host.
Viruses are called ‘Obligate parasites’ because they lack metabolic machinery of their own to generate energy or to synthesize proteins, so they are dependent on host cells to carry out those vital functions. They are host-dependent and can be cultured only in living cells. So the answer is option ‘A’ i.e. without independent metabolism.

Additional information:
Some of the characteristics of viruses are :
1. Viruses have an inner core of nucleic acid surrounded by a protein coat known as an envelope.
2. They are responsible for many dreadful diseases in humans and plants.
3. The host is a living thing that provides a source of energy for a virus or an organism.
4. It Can’t carry out metabolic processes such as metabolism and homeostasis.

Note: Viruses depend fully on the host cell machinery to continue their life, hence they are metabolically inefficient. Viruses are nearly dead outside a living cell since they derive nutrition from the host only because of a lack of independent metabolism.