![]() (For most organisms, a full complement of chromosomes is diploid, but They are produced by meiosis in the sporophyte, a structure whose cells have a full complement of chromosomes (usually diploid) and generates the spores. Spores are unicellular and haploid (having one-half of the genetic complement as have somatic, or body, cells). Spores contain DNA and can develop into new organisms after dispersal. The gametophyte produces haploid gametes, which fuse to form a diploid zygotic sporophyte. Haploid cells undergo mitosis to produce a gametophyte. A diploid (2n) sporophyte undergoes meiosis to produce haploid (1n) reproductive cells, often called spores. The term spore derives from the ancient Greek word σπορα, meaning seed. Sexual reproduction is widespread in nature and, combined with genetic recombination, promotes uniqueness among individuals.įungi that produce spores are known as sporogenous, and those that do not are asporogenous. Notably, although spores represent a type of asexual reproduction, for most organisms spores represent just part of a life cycle that also includes sexual reproduction. However, spores also reflect one aspect of life's great diversity, a diversity in nature that fascinates and can bring joy to human beings. Some spores, such as from mold, can be common allergens. However, they are more subject to fungal and bacterial infection. Also, spores are less subject to animal predation than seeds because they contain almost no food reserve. In the case of spore-shedding vascular plants, such as ferns, wind distribution of very light spores provides great capacity for dispersal. Spores' chief advantage is that, of all forms of progeny, spores require the least energy and materials to produce. The term spore can also be loosely applied to some animal resting stages. In addition to being reproductive structures, the term spore may also refer to the dormant stage of some bacteria or archaea however, these more correctly are known as endospores and are not truly spores in the sense discussed in this article. (See spore formation and life cycles below.) Being units of asexual reproduction, spores do not combine with other spores, but directly form new haploid organisms. They are typically unicellular and haploid, being produced by meiosis. Spores form part of the life cycles of many plants, algae, fungi, and some protozoans. In biology, a spore is a reproductive structure that is adapted for dispersion and survival for extended periods of time in unfavorable conditions. ![]()
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