Morphology of the trunk and development of the microsporangium of cycads ... by Frances Grace Smith Download PDF EPUB FB2
In this article we will discuss about Cycas. After reading this article you will learn about: 1. Distribution of Cycas 2. General Morphology of Cycas 3. Anatomy of Vegetative Parts 4. Economic Importance. Cycas, the largest genus among the Old World Cycads, is the most widely distributed genus of order Cycadales.
Other articles where Microsporangium is discussed: plant: Heterosporous life histories: Microsporangia (male sporangia) produce microsporocytes (micromeiocytes) that yield microspores. Megasporangia (female sporangia) produce megasporocytes (megameiocytes) that yield megaspores.
The sporangia may be borne in specialized structures such as sori in ferns. Morphology: Cycas sporophyte is an evergreen palm-like tree that attains a height of to mt. Sporophyte is dioecious i.e. male and female plants are separate.
Both the plant body is differentiated into roots, stem and leaves (Fig. Cycads: Systematics. The Cycadophyta (the cycads proper), comprise the three families Cycadaceae, Stangeriaceae, and Zamiaceae, with approximately extant species in 11 genera.
The group is recognized by the structure of its sporophylls, and by having pinnately compound leaves, though the genus Bowenia has doubly compound leaves, and some fossil. microsporangium[¦mīkrōspə′ranjēəm] (botany) A sporangium bearing microspores.
Microsporangium the multicellular organ of heterosporous Pteridophyta and seed plants in which the microspores develop. In Selaginella and Sigillaria the microsporangia are located singly in the axils of microsporophylls or on the upper-sides of the leaves (in.
Microsporangia are sporangia that produce microspores that give rise to male gametophytes when they germinate. Microsporangia occur in all vascular plants that have heterosporic life cycles, such as seed plants, spike mosses and the aquatic fern genus gymnosperms and angiosperm anthers, the microsporangia produce microsporocytes, the microspore mother.
Stamen is the Latin word meaning "thread" (originally thread of the warp, in weaving). Filament derives from classical Latin filum, meaning "thread" Anther derives from French anthère, from classical Latin anthera, meaning "medicine extracted from the flower" in turn from Ancient Greek ἀνθηρά, feminine of ἀνθηρός, "flowery.
Male Gametophyte Early development takes place inside the microsporangium Pollen grains are released at the 4- celled stage (2 prothalial, a generative cell and tube cell) Pollination is anemophilous and pollen reach the pollen chamber of the ovule through micropyle Further development here, results in the formation of pollen tube which.
Morphology, development and anatomy of the male cones of Zamia amblyphyllidia are studied here to amass additional information to develop a more convincing concept of. This banner text can have markup. web; books; video; audio; software; images; Toggle navigation. microsporangium A sporangium (e.g.
in heterosporous (see HETEROSPORY) ferns and the clubmoss Selaginella) that produces numerous minute spores which germinate to produce only male pteridophytes that produce them also produce megasporangia containing few (often only 1–4) large spores; these spores germinate to produce the female.
Angiosperms are the dominant form of plant life in most terrestrial ecosystems, comprising about 90 percent of all plant species. Most crops and ornamental plants are angiosperms. Their success comes from two innovative structures that protect reproduction from variability in the environment: the flower and the fruit.
"The Development of the Microsporangium and Microspores in Convallaria and Potamogeton" is an article from Botanical Gazette, Volume View more articles from Botanical Gazette.
View this article on JSTOR. View this article's JSTOR metadata. The internal male reproductive system of Lucilia cuprina consists of paired testes, paired vasa deferentia, one pair of tubular accessory glands and a single seminal duct equipped with a pumping organ The secretory activity of the accessory glands and the shape of the pumping organ both change with physiological age and can be used as age indicators The internal Cited by: A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text.
a sporangium that produces spores that give rise to male gametophytes. In Gymnosperms and Angiosperms (Flowering plants), the microsporangium produce the microsporocyte, also known as the microspore mother cell, which then creates four microspores through meiosis.
The microspores divide to create pollen grains. - fern like leaves- pinnate- petiole, rachis, pinnae - Thick stems with armor of bracts & leaf bases. - has manoxylic wood - coralloid roots - has sporophylls, which is microsporangia borne on abaxial surface of modified leaves on axis of simple pollen cones.
margins, and an acuminate or pointed tip. The trunk of the sago palm is dark brown and thick, and appears shaggy. Plants are either male or female and the reproductive structures are found in the center of the plant. The male organ resembles a large yellow cone that reaches lengths of up to 2 feet.
The female organ resembles a yellow furryFile Size: 2MB. Morphology of Cycads Morphology = form and structure. Stems of Cycads the swollen underground or aboveground stem is called a pastureland or other development, as well as poaching of plants from the wild by hobbyists or commer-cial collectors is wiping out the world’s cycads.
Cycads. Inspire a love of reading with Prime Book Box for Kids Discover delightful children's books with Prime Book Box, a subscription that delivers new books every 1, 2, or 3 months — new customers receive 30% off your first box.
Learn more. Enter your mobile number or email address below and we'll send you a link to download the free Kindle App. Author: F.H.
Connell. REPRODUCTIVE EVENTWith a few exceptions cycads show a high similarity in their reproductive events, from structuralmorphology to the accompanying ecology activities, I will thus describe the event in terms ofthese two categories—morphology and ecology—noting exceptions where logy of reproductive organsMale strobiliAll male.
Morphology, taxonomy and life cycle of parasites 1. they can cause diseases and/or can become a major contributing factor to disease development. They are generally divided into two groups- Ectoparasites- which live on the outside of the host(including the gill, mouth, skin and fin surfaces) Endoparasites- which live in tissues, blood or.
ADVERTISEMENTS: In this article we will discuss about: 1. Morphology and Lifecycle of Leishmania Tropica 2. Pathogenicity of Leishmania Tropica 3.
Treatment of Disease Caused. Morphology and Lifecycle of Leishmania Tropica: The morphology and life cycle of Leishmania Tropica resemble those of L. donovani.
The amastigote are present in the skin, within large. Chapter 23 summarizes the economic importance of gymnosperms. Chapter 24 gives the conciuding remarks.
Thus, there is a complete coverage of significant findings concerning morphology, anatomy, reproduction, development of embryo and seed, cytology, and -evolutionary trends and phylogeny. Morphology. Protozoans are single-celled eukaryotes. They are small organisms, ranging from a few microns in length up to about 1 mm.
Therefore, the study of protozoans requires patience and skill as a microscopist. Specialized staining and optical techniques are often required to visualize their internal structures.
The sequence of precoralloid initiation, maturation, cyanobacterial invasion, and coralloid development in M. communis has been described here, at the morphological level, for the first time in a cycad. The different stages of development can now be identified by specific charac.
For cone and ovule development, see Tomlinson et al. (), for pollination, see Tomlinson (, useful comparative table), Tomlinson et al. () and Rydin and Friis ( correlation between absence of wings and the pollen exine being shed on germination), for nucleus number in the E-tier cells, see Quinn (), and for phylogeny.
The morphology and the divisional morphogenesis of the freshwater hypotrich ciliate Parentocirrus hortualis nov. gen., nov. spec, has been investigated using living organisms and protargol impregnation. The morphogenesis commences with the proliferation of basal bodies for the opisthe's oral primordium left of two anteriormost and unchanged transverse cirri, Cited by: 6.
Anatomy & Morphology of Conifer Tree Seed This publication from the BC Ministry of Forests describes the anatomical and morphological characteristics of conifer seeds as well as germination, dormancy, and seed tests. In addition, eight conifer genera are profiled. Anatomy & Morphology of Conifer Tree Seed.
Buy Cytological and morphological studies in the genus Ficus: II. Chromosome number and morphology in thirty-one species (University of California publications in botany) on FREE SHIPPING on qualified ordersAuthor: Ira Judson Condit.
Abstract. The present communication deals with the morphology, reproduction and cytology of Stigeoclonium pascheri (formerly described as Caespitella pascheri Vischer). Effects of various concentrations of nitrate and variations in intensity and duration of light period in 24 hr LD cycles were studied on cultures of this alga in relation to the type and extent of branching and Cited by: 5.
The cycads constitute a homogeneous group of a few living members confined to tropical and sub-tropical regions. As a fairly typical and well-known example of the Cycadaceae, a species of the genus Cycas (e.g.
C. circinalis, C. revoluta, &c.) is briefly described. The stout columnar stem may reach a height of 20 metres, and a diameter of half a metre; it remains I.: Pteridospermae (see Palaeobotany, Palaeozoic).The embryology and metamorphosis of the Macroura / Related Titles.
Series: Memoirs of the National Academy of Sciences v. 5, 4th memoir. By. Brooks, William Keith, Herrick, Francis Hobart, National Academy of Sciences (U.S.) Type. Book Material. Published material. Publication info.