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is a tiny nonliving particle that enters and then reproduces inside a living cell.


is an organism that provides a source of energy for a virus or another organism.


an organism that lives on or in a host and causes it harm


is a virus that infects 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


a tiny structure in the cytoplasm of a cell where proteins are made


a long, whiplike structure that helps a cell to move

Binary Fission

a form of asexual reproduction in single-celled organisms by which one cell divides into two cells of the same size

Asexual Reproduction

process by which a single parent reproduces by itself

Sexual Reproduction

process by which cells from two different parents unite to produce the first cell of a new organism


form of sexual reproduction in which paramecia and some prokaryotes exchange genetic information


a small asexual spore that develops inside the cell of some bacteria and algae


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


organism that breaks down and obtains energy from dead organic matter


the process by which cells break down simple food molecules to release the energy they contain


a chemical substance derivable from a mold or bacterium that kills microorganisms and cures infections

Infectious Disease

Illness that passes from one organism to another

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