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Sporogenesis is the production of spores in biology. The term is also used to refer to the process of reproduction via spores. Reproductive spores were found to be formed in eukaryotic organisms, such as plants , algae and fungi , during their normal reproductive life cycle .
Examples of vegetative reproduction include the formation of miniaturized plants called plantlets on specialized leaves, for example in kalanchoe (Bryophyllum daigremontianum) and many produce new plants from rhizomes or stolon (for example in strawberry). Some plants reproduce by forming bulbs or tubers, for example tulip bulbs and Dahlia ...
Usually, eggs are laid only by the queen, but the unmated workers may also lay haploid, male eggs either regularly (e.g. stingless bees) or under special circumstances. An example of non-viable parthenogenesis is common among domesticated honey bees. The queen bee is the only fertile female in the hive; if she dies without the possibility of a ...
The second more recent hypothesis is that spores were an early predecessor of land plants and formed during errors in the meiosis of algae, a hypothesized early ancestor of land plants. [ 18 ] Whether spores arose before or after land plants, their contributions to topics in fields like paleontology and plant phylogenetics have been useful. [ 18 ]
Plant reproductive morphology is the study of the physical form and structure (the morphology) of those parts of plants directly or indirectly concerned with sexual reproduction. Among all living organisms, flowers , which are the reproductive structures of angiosperms , are the most varied physically and show a correspondingly great diversity ...
Plant reproduction is the production of new offspring in plants, which can be accomplished by sexual or asexual reproduction. Sexual reproduction produces offspring by the fusion of gametes , resulting in offspring genetically different from either parent.
Early land plants had sporophytes that produced identical spores (isosporous or homosporous) but the ancestors of the gymnosperms evolved complex heterosporous life cycles in which the spores producing male and female gametophytes were of different sizes, the female megaspores tending to be larger, and fewer in number, than the male microspores.
A female pinecone produces the megaspores of this heterosporic plant. A male pinecone produces the microspores of this heterosporic plant. Heterospory is the production of spores of two different sizes and sexes by the sporophytes of land plants. The smaller of these, the microspore, is male and the larger megaspore is female.