Question

Given below are two statements, one is labelled as Assertion (A) and other labelled as Reason (R).
Assertion (A): Plant viruses multiplies within the plant cell expoliting cell machinary
Reason (R): Plant viruses lack elaborate metabolic capabilities
In light of the above statements, choose the most appropriate answer from the options given below:

• A. Both (A) and (R) are true and (R) is the correct explanation of (A).
• B. Both (A) and (R) are true but (R) is NOT the correct explanation of (A).
• C. (A) is true but (R) is false.
• D. (A) is false but (R) is true.

Hint:

Viruses are defined as non-cellular, obligate intracellular parasites because they lack their own translational and metabolic machinery.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
Viruses are obligate intracellular parasites that contain either a DNA or RNA genome enclosed in a protective protein coat (capsid).
They cannot reproduce or metabolize independently outside of a host cell.

Step 2: Detailed Explanation:
Let us analyze both statements:
- Assertion (A) is true: Once inside a host plant cell, a virus must disassemble to release its genome.
To replicate and produce new viral particles, it must exploit the host cell's machinery, utilizing host ribosomes, tRNA, enzymes, nucleotides, amino acids, and energy (ATP).
- Reason (R) is true: Viruses lack metabolic capabilities, ribosomes, and protein-synthetic machinery.
They cannot generate energy or synthesize their own proteins independently.
Because they lack this metabolic machinery, they must infect a host cell and use its replication and translation systems to produce viral components.
Thus, Reason (R) is correct and directly explains why Assertion (A) is correct.

Step 3: Final Answer:
Hence, the correct option is (A).