The thick-walled structure of the spore is resistant to heat and it can help the pathogenic bacteria survive the heat of cooking. Spore-Forming Pathogenic Bacteria in Ready-to-Eat Foodīacillus cereus and Clostridium perfringens are examples of pathogenic bacteria that can exist in both spore and vegetative forms. Few of them can also exist in spore form which is unable to grow or reproduce but can help the bacteria to survive in an environment that is unfavourable for growth. Bacteria can live in a vegetative state in which they can grow and reproduce.
We would continue to discuss pathogenic bacteria in this issue.Īpart from the weapon – toxins, some pathogenic bacteria have a shield to help them survive the cooking process. In the last issue, we presented spoilage and pathogenic bacteria in food as well as various ways of toxin production by pathogenic bacteria. Risk Assessment Section, Centre for Food Safety Sporulā′tion, conversion into spores or sporules-also Sporā′tion Spō′rule, a small spore.- adjs.Food Safety Focus (25th Issue, August 2008) – Food Safety Platform Biological Hazard in Food – Pathogenic Bacteria (Part II) Spō′rosac, one of the gonophores of certain hydrozoans in which the medusoid structure is not developed: a redia or spiro-cyst, in Vermes Sporostē′gium, the so-called fruit of plants in the Characeæ, consisting of the hard brownish spirally-twisted shell or covering of the spore.- adjs. Spō′rophyl, the leaf bearing the spores or spore receptacles Spō′rophyte, the spore-bearing stage in the life-cycle of a plant.- adj. Sporol′ogist, a botanist who emphasises the spores in classification Spō′rophore, the part of the thallus which bears spores: the placenta in flowering plants: a sporophyte.- adjs. Sporogō′nium, the sporocarp, capsule or so-called 'moss-fruit' in mosses.- adj. Spō′roderm, the wall or covering of a spore Sporogen′esis, reproduction by means of spores-also Sporog′eny.- adj. Spō′rocarp, a many-celled form of fruit produced in certain lower cryptogams in consequence of a sexual act Spō′rocyst, the cyst or capsule developed in the process of sporular encystment.- adj.
Spore definition biology free#
Sporan′gia), a spore-case, the sac in which the spores are produced endogenously-also Spore′-case Spō′ridesm ( bot.), a pluricellular body which becomes free like a simple spore, and in which every cell is capable of germinating Sporidī′olum, a secondary sporidium Sporid′ium, a secondary spore borne on a promycelium: an ascospore Sporificā′tion, spore-production Sporipar′ity, reproduction by means of spores.- adj. Sporangī′olum, a small sporangium Sporan′giophōre, the receptacle which bears the sporangia Sporan′giospōre, one of the peculiar spores of the Myxomycetes Sporan′gium ( pl. Sporan′gial Sporangif′erous Sporan′giform Sporan′gioid, like a sporangium.- ns. the reproductive body in flowerless plants like the fern, analogous to the seeds of ordinary flowering plants, but containing no embryo: a germ, a seed, a source of being generally.- adjs. 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.Ĭhambers 20th Century Dictionary (0.00 / 0 votes) Rate this definition: 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. In bacteria, 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. Freebase (0.00 / 0 votes) Rate this definition:
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