Which of the following is not true for retroviruses?

Explanation

The first option is correct: Retroviruses are not cuboidal in shape. Retroviruses are actually spherical or roughly spherical in shape. Their structure consists of a lipid envelope derived from the host plasma membrane, which surrounds the viral capsid. The viral capsid contains the genetic material of the virus. The second option is incorrect: Retroviruses are indeed enveloped by the host plasma membrane. When a retrovirus infects a host cell, it enters the cell by fusing its envelope with the host cell's plasma membrane. This allows the viral genetic material to enter the host cell. The third option is incorrect: Retroviruses do possess an enzyme called reverse transcriptase. Reverse transcriptase is a unique enzyme that allows retroviruses to convert their RNA genome into DNA. This DNA copy is then integrated into the host cell's genome, where it can be transcribed and translated to produce new viral particles. The fourth option is incorrect: Retroviruses are generally considered to be specific in their host range. Each retrovirus typically infects a specific host species or a limited range of related species. For example, HIV (human immunodeficiency virus) is a retrovirus that primarily infects humans. However, certain retroviruses, known as xenotropic retroviruses, have the ability to infect cells from species other than their usual host, although they may not necessarily cause disease in those species.