In biology, a<unk>  is a reproductive structure that is adapted for dispersion and surviving for extended periods of time in unfavorable conditions.<unk> s form part of the life cycles of many plants, algae, fungi and some protozoans.<unk> s are usually haploid and unicellular and are produced by meiosis in the<unk> phyte. Once conditions are favorable, the<unk>  can develop into a new organism using mitotic division, producing a multicellular gametophyte, which eventually go on to produce gametes. Two gametes fuse to create a new<unk> phyte. This cycle is known as alternation of generations, but a better term is "biological life cycle", as there may be more than one phase and so it cannot be an alternation. Haploid<unk> s produced by mitosis (known as mitospores) are used by many fungi for asexual reproduction.<unk> s are the units of asexual reproduction as a single<unk>  develops into a new organism.  By contrast, gametes are the units of sexual reproduction as two gametes need to fuse to create a new organism.
The term<unk>  may also refer to the dormant stage of some bacteria or archaea; however these are more correctly known as endospores and are not truly<unk> s in the sense discussed in this article. The term can also be loosely applied to some animal resting stages. Fungi that produce<unk> s are known as<unk> genous, and those that do not are asporogenous.
The term derives from the ancient Greek word σπορα, meaning seed.
Spore
Slug
Floater
Boil
Gamete
Hair
Clavicle
Nucleosol