Infrequently septate, multi-nucleate hyphae as in the Zygomycetes.Ī small collar. Chlamydoconidia function as organs of perennation rather than dissemination.Ī specialized hyphal bridge over a septum in the Basidiomycetes.Īn enclosed ascocarp containing randomly dispersed asci. Cryptococcus and Rhodotorula.Ī thick-walled, thallic conidium formed within the vegetative hyphae. Usually used to denote the young blastoconidia of yeasts.Īsexual multiplication by the production of a small outgrowth or bud from a parent cell.Ī hyaline mucopolysaccharide sheath around the cell wall of certain yeasts e.g. Two or rarely three levels of branching directly below the phialides as in the genus Penicillium.Ī form of conidial development where there is a recognizable enlargement or "blowing out" of a conidial initial before being delimited by a septum.Ī chain of conidia having the youngest cell at the tip.Īn asexual conidium that forms by a blowing out or budding process.Ī young conidium. Phialides arising from metulae as in the genus Aspergillus. Basidia are characteristic of the Basidiomycetes.Ī chain of conidia, the oldest conidium is at the apex and the youngest is at the base.Ī chain of conidia having the youngest cell at the base.īlastoconidia developing at the opposite poles of a parent cell. Lacking septa, often pertaining to the hyphae seen in zygomycetes (also see coenocytic).Ī group of fungi that reproduce sexually by the exogenous formation of basidiospores from a basidium.Ī haploid spore produced on a basidium following karyogamy and meiosis.Ī cell that gives rise to a basidiospore. Asci are characteristic of the Ascomycetes. The term is primarily applied to the funnel-shaped swelling of a sporangiophore, immediately below the columella, seen in some zygomycetes.Ī type of conidial ontogeny involving the conversion and subsequent disarticulation of a determinant conidiogenous hypha.Ī thallic conidium released by either the splitting of a double septum or by the fragmentation or lysis of a disjunctor cell.Ī fruiting body containing asci and ascospores.Ī group of fungi that reproduce sexually by the endogenous formation of ascospores in an ascus.Ī haploid spore produced within an ascus following karyogamy and meiosis.Ī sac-like cell containing ascospores. The tip of an annellide increases in length and becomes narrower as each subsequent conidium is formed.Ī swelling.
#Spore definition biology series
Hyphal elements growing above the agar surface.Ī thallic conidium released by lysis or fracture of the supporting cell.Ī specialized conidiogenous cell producing conidia in basipetal succession by a series of short percurrent proliferations (annellations). TermĬonidia developing at the tip and along the sides of the conidiophore.Ī large, globose, thick-walled conidium, usually produced by Emmonsia ( Chrysosporium) parvum, in the lungs of humans and animals. Ainsworth & Bisby's Dictionary of the fungi. The spores of seed plants, however, are produced internally and the megaspores, formed within the ovules and the microspores are involved in the formation of more complex structures that form the dispersal units, the seeds and pollen grains.Additional reference: Hawksworth DL, PM Kirk, BC Sutton, DN Pegler. This cycle is known as alternation of generations.
Two gametes fuse to form a zygote which develops into a new sporophyte. Under favourable conditions the spore can develop into a new organism using mitotic division, producing a multicellular gametophyte, which eventually goes on to produce gametes. Spores are usually haploid and unicellular and are produced by meiosis in the sporangium of a diploid sporophyte. Myxozoan spores release amoebulae into their hosts for parasitic infection, but also reproduce within the hosts through the pairing of two nuclei within the plasmodium, which develops from the amoebula. Bacterial spores are not part of a sexual cycle but are resistant structures used for survival under unfavourable conditions. Spores form part of the life cycles of many plants, algae, fungi and protozoa. By contrast, gametes are units of sexual reproduction. In biology, a spore is a unit of asexual reproduction that may be adapted for dispersal and for survival, often for extended periods of time, in unfavorable conditions.
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