Question

Explain in detail why this statement is FALSE:

"Viruses infect bacteria and reproduce by delivering proteins into their cytoplasm."

Answer 1

Viruses infect bacteria and reproduce by delivering viral genome into the cytoplasm not proteins.

Viral replication /reproduction occurs in 6 stages include attachment, penetration, uncoating, biosynthesis, maturation, and release.

Attachment

A virus attaches on the host cell membrane at specific receptor site with the help of attachment proteins.

Penetration and uncoating

The viral genome (nucleic acid)  of bacteriophages enters the host cell, leaving the capsid outside the cell.

Some enveloped viruses enter as a whole by fusion with the cell membrane. After getting inside the cell, t the viral nucleic acid is released and the viral capsid is degraded. The released viral genome is utilized for replication and transcription.

Replication and Assembly

DNA viruses - use host cell proteins and enzymes and produce additional DNA , that DNA is transcribed to messenger RNA (mRNA), which is translated to protein.

DNA--------> mRNA ------>Protein

RNA viruses - use the RNA core as a template and produce viral genomic RNA and mRNA. The viral mRNA directs the host cell to produce viral enzymes and capsid proteins, and to assemble new virions.

RNA-------> mRNA------> Protein

There are few exceptions. If proteins or enzymes are missing in host for viral replication, (RETEROVIRUS), viral genes give the needed information to regulate the synthesis of the missing proteins. Reterovisus have the ability of reverse transcription by using enzyme reverse transcriptase.

RNA------> DNA ----->mRNA------> proteins

By following any one of the mechanism viral genome and proteins are replicated and get assembled

Release

The last stage of viral replication is the release of the new virions from host organism.. Some viruses are released when the host cell dies, while other viruses can leave infected cells by budding through the membrane without directly killing the cell. Now the new virus is able to infect adjacent cells and repeat the replication cycle.