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


An organism that provide a source of energy or a suitable enviroment for a virus or another or organism to live.


An organism that lives on or in a host and causes harm to the host.


A virus that infects the bacteria


single-celled organisms that lack a nucleus; prokaryotes


the region of the cell within the membrane that includes the fluid, the cytoskeleton, and all of the organelles except the nucleus


the process of breaking down food release its energy.


long, whip-like structure that helps a cell to move


the process of braking down food to release its energy.

binary fission

a form of asexual reproduction in which one cell divides to form two identical cells

asexual reproduction

The reproductive process that involves only one parent and produces offspring that are identical to the parent

sexual reproduction

A reproductive process that involves two parents that combine their genetic material to produce a new organism, which differs from both parents.


the process in which a unicellular organism transfers some of its genetic material to another unicellular organism


A small, rounded, thick-walled, resting cell that forms inside a bacterial cell


a process of heating food to a temperature that is high enough to kill most harmful bacteria without changing the taste of food


an organism that breaks down chemicals from dead organisms and returns important materials to the soil and water

infectious disease

An illness that can pass from one organism to another


single-celled organisms that lack a nucleus; prokaryotes

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