Virus A tiny, nonliving particle that invades and then reproduces inside a living cell

Host Cell An organism that provides a source of energy for a virus or another organism

Bacteriophage viruses that infect bacteria

Capsid a protein coat that may contain RNA or DNA but not both

Lytic Cycle Cycle of infection, replication and cell destruction

Lysogenic Cycle cell divides, the provirus also divides, resulting in two infected host cells.

Provirus viral gene that is inserted into the host chromosome

Retrovirus RNA virus that contains reverse transcriptase

Reverse Transcriptase uses RNA as a template to make DNA is an enzyme used to generate complementary DNA (cDNA) from an RNA template

Prion an infectious agent that is composed primarily of protein.

Viroid Viroids are plant pathogens that consist of a short stretch of highly complementary, circular, single-stranded RNA.

Chemiosynthesis the biological conversion of one or more carbon molecules (usually carbon dioxide or methane)

Binary Fission Where one bacterium divides to form two identical bacteria cells

Conjugation The process in which two bacteria exchange genetic material

Obligate Aerobe is an aerobic organism that requires oxygen to grow

Obligate Anaerobe are microorganisms that live and grow in the absence of molecular oxygen; some of these are killed by oxygen

Endospore Small, rounded, thick- walled, resting cell that forms inside a bacterial cell

Toxin Poison produced by bacteria

Nitrogen Fixation is a process by which nitrogen (N2) in the atmosphere is converted into ammonia (NH3)