DENDROLOGY

Detailed explanation-1: -Virology is the study of viruses and virus-like agents, including, but not limited to, their taxonomy, disease-producing properties, cultivation, and genetics. Virology is often considered a part of microbiology or pathology.

Detailed explanation-2: -Viruses are small, subcellular agents that are unable to multiply outside a host cell (intracellular, obligate parasitism). The assembled virus (virion) is formed to include only one type of nucleic acid (RNA or DNA) and, in the simplest viruses, a protective protein coat.

Detailed explanation-3: -By studying viruses, we can learn about the biology of host cells and organisms, develop strategies against viral disease and manipulate viruses for our own purposes. Some viruses are only a single self-replicating gene, while others can encode almost a thousand proteins and be the size of a bacterium.