Small land plant spores that develop into male gametophytes
Microscopic photo of spores (in red) of Selaginella. The large three spores at the top are megaspores whereas the numerous smaller red spores at the bottom are microspores.
Microspores are land plant spores that develop into male gametophytes, whereas megaspores develop into female gametophytes.[1] The male gametophyte gives rise to sperm cells, which are used for fertilization of an egg cell to form a zygote. Megaspores are structures that are part of the alternation of generations in many seedless vascular cryptogams, all gymnosperms and all angiosperms. Plants with heterosporous life cycles using microspores and megaspores arose independently in several plant groups during the Devonian period.[2] Microspores are haploid, and are produced from diploid microsporocytes by meiosis.[3]
^Evert, Ray (2013). Biology of Plants. New York: Peter Marshall. ISBN 978-1-4292-1961-7.
^Bateman, R.M.; Dimichele, W.A. (1994). "Heterospory – the most iterative key innovation in the evolutionary history of the plant kingdom". Biological Reviews of the Cambridge Philosophical Society. 69 (3): 345–417. doi:10.1111/j.1469-185x.1994.tb01276.x. S2CID 29709953.
^Bidlack, James E.; Jansky, Shelley H. (2011). Stern's Introductory Plant Biology. New York, NY: McGraw-Hill. ISBN 978-0-07-304052-3.
Microspores are land plant spores that develop into male gametophytes, whereas megaspores develop into female gametophytes. The male gametophyte gives...
and sexes by the sporophytes of land plants. The smaller of these, the microspore, is male and the larger megaspore is female. Heterospory evolved during...
diploid microspore mother cells. These microspore mother cells, also called microsporocytes, then undergo meiosis and become four microspore haploid cells...
produced internally, and the megaspores (formed within the ovules) and the microspores are involved in the formation of more complex structures that form the...
extension on the dorsal side of the anther. A pollen grain develops from a microspore in the microsporangium and contains the male gametophyte. The size of...
A microsporangium (pl. microsporangia) is a sporangium that produces microspores that give rise to male gametophytes when they germinate. Microsporangia...
which are heterosporous, microspores and megaspores are dispersed from sporangia either passively or by active ejection. Microspores produce microgametophytes...
contains diploid microspore mother cells, or microsporocytes. Each microsporocyte undergoes meiosis, forming four haploid microspores, each of which can...
called an inflorescence. Flowers produce two kinds of reproductive cells. Microspores, which divide to become pollen grains, are the male cells; they are borne...
for the microspores that form by meiotic division from the sporogenous cells. In a process called microsporogenesis, four haploid microspores are produced...
heterosporous plants. These plants have two spore types, megaspores and microspores. Generally speaking, the megaspore, or large spore, germinates into a...
Like all seed plants, they are heterosporous, having two spore types, microspores (male) and megaspores (female) that are typically produced in pollen...
a heterosporous plant, producing microspores that contain the male gametophyte. Compare megasporangium. microspore The smaller of two kinds of spores...
depend on meiosis. Meiosis is central to the processes by which diploid microspore mother cells within the anther give rise to haploid pollen grains, and...
distinct sizes (heterospory or anisospory): larger megaspores and smaller microspores. When the two kinds of spore are produced in different kinds of sporangia...
and female cones. In the male cones, microspores are produced from microsporocytes by meiosis. The microspores develop into pollen grains, which contain...
role in the strand-exchange reactions of meiotic recombinational repair. Microspore, spores that develop into male gametophytes Solomon, Eldra P., 2005, Biology...
their spores were of two distinct sizes, larger megaspores and smaller microspores. Their reduced gametophytes developed from megaspores retained within...
sporangium, the microsporangium, produces microspores. A tiny gametophyte develops inside the wall of a microspore, producing a pollen grain. Pollen grains...
male sporangia. Male spores (microspores) are extremely small and are produced inside each microsporangium. Microspores tend to adhere in clumps called...
anisogamous species, the two sexes are referred to as male (producing sperm or microspores) and female (producing ova or megaspores). In isogamous species, the...
the central cell) (the synergids and the antipodal cells). The haploid microspore passes through a mitosis to create a vegetative and generative cell during...
exserted. The plants demonstrate simultaneous microsporogenesis, the microspores are tetrad, tetrahedral, or isobilateral. The pollen grains are bicellular...
techniques exist to create DHs. The in vitro culture of anthers and microspores is most often used in cereals, including triticale. These two techniques...
megaspores tending to be larger, and fewer in number, than the male microspores. During the Devonian period several plant groups independently evolved...
heterosporous (two kinds of spores are produced).: 18 These plants produce both microspores and megaspores, which give rise to gametophytes that are functionally...
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