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The entire gametophyte generation, with the sole exception of pollen grains (microgametophytes), is contained within the sporophyte. The life cycle of a dioecious flowering plant (angiosperm), the willow, has been outlined in some detail in an earlier section (A complex life cycle). The life cycle of a gymnosperm is similar.
In biology, a biological life cycle (or just life cycle when the biological context is clear) is a series of stages of the life of an organism, that begins as a zygote, often in an egg, and concludes as an adult that reproduces, producing an offspring in the form of a new zygote which then itself goes through the same series of stages, the ...
Diagram showing the alternation of generations between a diploid sporophyte (bottom) and a haploid gametophyte (top) A sporophyte (/ ˈ s p ɔːr. ə ˌ f aɪ t /) is the diploid multicellular stage in the life cycle of a plant or alga which produces asexual spores. This stage alternates with a multicellular haploid gametophyte phase.
Gametogenesis is a biological process by which diploid or haploid precursor cells undergo cell division and differentiation to form mature haploid gametes.Depending on the biological life cycle of the organism, gametogenesis occurs by meiotic division of diploid gametocytes into various gametes, or by mitosis.
The life cycle of a floral plant — angiosperm. Date: 13 February 2007: Source: did it myself based in at least 5 illustrations but mainly on a image from Judd, Walter S. , Campbell, Christopher S. , Kellog, Elizabeth A. and Stevens, Peter F. 1999. Plant Systematics: A Phylogenetic. Approach.Sinauer Associates Inc. ISBN 0-878934049. Author
In 1835, the German botanist and physician Hugo von Mohl described plant cell division in much greater detail in his dissertation on freshwater and seawater algae for his PhD thesis in medicine and surgery: [54] "Among the most obscure phenomena of plant life is the manner in which the newly developing cells are formed.
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Evidence of fascioliasis in humans exists dating back to Egyptian mummies that have been found there are with Fasciola eggs. [14] Cercariae of F. hepatica in a snail and flukes infecting sheep were first observed in 1379 by Jehan De Brie. [13] [15] The life cycle and hatching of an egg were first described in 1803 by Zeder. [16]