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In trilete spores, each spore shows three narrow lines radiating from a center pole. [8] This shows that four spores shared a common origin and were initially in contact with each other forming a tetrahedron. [3] A wider aperture in the shape of a groove may be termed a colpus. [8] The number of colpi distinguishes major groups of plants.
The process of endospore formation has profound morphological and physiological consequences: radical post-replicative remodelling of two progeny cells, accompanied eventually by cessation of metabolic activity in one daughter cell (the spore) and death by lysis of the other (the 'mother cell').
The term sporogenesis can also refer to endospore formation in bacteria, which allows the cells to survive unfavorable conditions. Endospores are not reproductive structures and their formation does not require cell fusion or division. Instead, they form through the production of an encapsulating spore coat within the spore-forming cell.
As a model organism, B. subtilis is commonly used in laboratory studies directed at discovering the fundamental properties and characteristics of Gram-positive spore-forming bacteria. [29] In particular, the basic principles and mechanisms underlying formation of the durable endospore have been deduced from studies of spore formation in B ...
The resting spores produced may be either exogeneous (mature spore has no contact with parent cell), endogenous (completely enclosed within the parent cell), or semi-endogenous (only the hypovalve of the resting spore enclosed within the parent thecae). [6] The common characteristic of diatom resting spores is a thick silica frustule. Generally ...
The most common differentiation is the formation of a bottle shaped cell called a phialide, from which the spores are produced. Not all of these asexual structures are a single hypha. Not all of these asexual structures are a single hypha.
In the last group, rhizoids of compatible strains meet and fuse. Both nuclei migrate out of the zoosporangium and into the conjoined rhizoids where they fuse. The resulting zygote germinates into a resting spore. [2] Sexual reproduction is common and well known among members of the Monoblepharidomycetes.
However, both events (spore formation and fertilization) are necessary to complete sexual reproduction in the plant life cycle. Fungi and some algae can also utilize true asexual spore formation, which involves mitosis giving rise to reproductive cells called mitospores that develop into a new organism after dispersal.