FACTOID # 8: Bookworms: Vermont has the highest number of high school teachers per capita and third highest number of librarians per capita.
 
 Home   Encyclopedia   Statistics   States A-Z   Flags   Maps   FAQ   About 
 
WHAT'S NEW
RELATED ARTICLES
People who viewed "Gymnosperm" also viewed:
 

SEARCH ALL

FACTS & STATISTICS    Advanced view

Search encyclopedia, statistics and forums:

 

 

(* = Graphable)

 

 


Encyclopedia > Gymnosperm
Gymnosperms
White Spruce leaves (needles)
White Spruce leaves (needles)
Scientific classification
Kingdom: Plantae
Divisions

Pinophyta (or Coniferophyta) - Conifers
Ginkgophyta - Ginkgo
Cycadophyta - Cycads
Gnetophyta - Gnetum, Ephedra, Welwitschia Image File history File links Download high-resolution version (1024x1280, 205 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Leaf Gymnosperm ... Binomial name (Moench) Voss The White Spruce (Picea glauca) is a medium-sized evergreen tree growing to 15-30 m tall, rarely to 40 m tall, and with a trunk diameter of up to 1 m. ... Scientific classification redirects here. ... For other uses, see Plant (disambiguation). ... In biology, the equivalent of a phylum in the plant or the fungal kingdom is called a division. ... Orders & Families Cordaitales † Pinales   Pinaceae - Pine family   Araucariaceae - Araucaria family   Podocarpaceae - Yellow-wood family   Sciadopityaceae - Umbrella-pine family   Cupressaceae - Cypress family   Cephalotaxaceae - Plum-yew family   Taxaceae - Yew family Vojnovskyales † Voltziales † “Conifer” redirects here. ... Species G. biloba L. The Ginkgo (Ginkgo biloba; 銀杏 in Chinese), frequently misspelled as Gingko, and also known as the Maidenhair Tree, is a unique tree with no close living relatives. ... Families Cycadaceae cycas family Stangeriaceae stangeria family Zamiaceae zamia family Leaves and male cone of Cycas revoluta Cycads are an ancient group of seed plants characterized by a large crown of compound leaves and a stout trunk. ... taxa: Gnetales Welwitschiales Ephedrales The plant division Gnetophyta or gnetophytes comprise three related families of woody plants grouped in the gymnosperms, a paraphyletic group of seed plant divisions. ...

Gymnosperm (Gymnospermae) are a group of spermatophyte seed-bearing plants with ovules on the edge or blade of an open sporophyll, which are usually arranged in cone-like structures. The other major group of seed-bearing plants, the angiosperms, have ovules enclosed in a carpel, a sporophyll with fused margins. The term gymnosperm comes from the Greek word gumnospermos, meaning "naked seeds" and referring to the unenclosed condition of the seeds, as when they are produced they are found naked on the scales of a cone or similar structure. Often they are used for many economical uses and as folk medicines. Some common uses for them are soap, varnish, lumber, paint, edible plants, and perfumes. The spermatophytes (also known as phanerogams) comprise those plants that produce seeds. ... For other uses, see Plant (disambiguation). ... This article or section does not adequately cite its references or sources. ... A sporophyll is a a spore-bearing leaf located on plants such as ferns or algae. ... Classes Magnoliopsida - Dicots Liliopsida - Monocots The flowering plants (also angiosperms or Magnoliophyta) are one of the major groups of modern plants, comprising those that produce seeds in specialized reproductive organs called flowers, where the ovulary or carpel is enclosed. ... Amaryllis style and stigmas A carpel is the outer, often visible part of the female reproductive organ of a flower; the basic unit of the gynoecium. ... For other uses, see Soap (disambiguation). ... Varnish is a transparent, hard, protective finish or film primarily used in wood finishing but also for other materials. ... Timber in storage for later processing at a sawmill roni Lumber or timber is a term used to describe wood, either standing or that has been processed for use — from the time trees are felled, to its end product as a material suitable for industrial use — as structural material for... For other uses, see Paint (disambiguation). ... For other uses, see Perfume (disambiguation). ...


Gymnosperms are heterosporous, producing microspores that develop into pollen grains and megaspores that are retained in an ovule. After fertilization (joining of the micro- and megaspore), the resulting embryo, along with other cells comprising the ovule, develops into a seed. The seed is a sporophyte resting stage. Reproduction in gymnosperms varies greatly. Cycads and Ginkgo have motile sperm that swim directly to the egg inside the ovule, while conifers and gnetophytes have sperm with no flagella that are conveyed to the egg along a pollen tube which grows through ovule tissue. Heterosporous plants, such as spikemosses, quillworts, and some aquatic ferns produce spores of two different sizes: the larger spore effectively functioning as a female spore and the smaller functionally male. ... SEM image of pollen grains from a variety of common plants: sunflower (Helianthus annuus), morning glory (Ipomoea purpurea), prairie hollyhock (Sidalcea malviflora), oriental lily (Lilium auratum), evening primrose (Oenothera fruticosa), and castor bean (Ricinus communis). ... Families Cycadaceae cycas family Stangeriaceae stangeria family Zamiaceae zamia family Leaves and male cone of Cycas revoluta Cycads are an ancient group of seed plants characterized by a large crown of compound leaves and a stout trunk. ... Species G. biloba L. The Ginkgo (Ginkgo biloba; 銀杏 in Chinese), frequently misspelled as Gingko, and also known as the Maidenhair Tree, is a unique tree with no close living relatives. ... Orders & Families Cordaitales † Pinales   Pinaceae - Pine family   Araucariaceae - Araucaria family   Podocarpaceae - Yellow-wood family   Sciadopityaceae - Umbrella-pine family   Cupressaceae - Cypress family   Cephalotaxaceae - Plum-yew family   Taxaceae - Yew family Vojnovskyales † Voltziales † The conifers, division Pinophyta, are one of 13 or 14 division level taxa within the Kingdom Plantae. ... taxa: Gnetales Welwitschiales Ephedrales The plant division Gnetophyta or gnetophytes comprise three related families of woody plants grouped in the gymnosperms, a paraphyletic group of seed plant divisions. ... A flagellum (plural, flagella) is a whip-like organelle that many unicellular organisms, and some multicellular ones, use to move about. ... Pollen may refer to the microspores of either angiosperms (flowering plants) or gymnosperms (conifers and cycads). ...

In early classification schemes, the gymnosperms (Gymnospermae) "naked seed" plants were regarded as a "natural" group. However, certain fossil discoveries suggest that the angiosperms evolved from a gymnosperm ancestor, which would make the gymnosperms a paraphyletic group if all extinct taxa are included. Modern cladistics only accepts taxa that are monophyletic, traceable to a common ancestor and inclusive of all descendants of that common ancestor. So, while the term 'gymnosperm' is still widely used for non-angiosperm seed-bearing plants, the plant species once treated as gymnosperms are usually distributed among four groups, which can be given equal rank as divisions within the Kingdom Plantae. Image File history File links Coast Douglas-fir cone - photo MPF From a tree grown from seed collected by David Douglas File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Image File history File links Coast Douglas-fir cone - photo MPF From a tree grown from seed collected by David Douglas File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Binomial name Pseudotsuga menziesii (Mirb. ... Paraphyletic - Wikipedia /**/ @import /skins-1. ... It has been suggested that Clade be merged into this article or section. ... In phylogenetics, a group is monophyletic (Greek: of one stem) if all organisms in that group are known to have developed from a common ancestral form, and all descendants of that form are included in the group. ...


Molecular phylogenies of extant gymnosperms have conflicted with morphological datasets with regard to whether they comprise a monophyletic group or a paraphyletic one that gave rise to angiosperms. At issue is whether the Gnetophyta are the sister group of angiosperms, or whether they are sister to, or nested within, other extant gymnosperms. Numerous fossil gymnosperm clades once existed that are morphologically at least as distinctive as the four living gymnosperm groups, such as Bennettitales, Caytonia and the glossopterids. When these groups are considered the question of gymnosperm and angiosperm relationships becomes even more complicated. In biology, phylogenetics (Greek: phylon = tribe, race and genetikos = relative to birth, from genesis = birth) is the study of evolutionary relatedness among various groups of organisms (e. ... In phylogenetics, a group is monophyletic (Greek: of one race) if it consists of a common ancestor and all its descendants. ... Paraphyletic - Wikipedia /**/ @import /skins-1. ... taxa: Gnetales Welwitschiales Ephedrales The plant division Gnetophyta or gnetophytes comprise three related families of woody plants grouped in the gymnosperms, a paraphyletic group of seed plant divisions. ... This cladogram shows the relationship among various insect groups. ... A clade is a term belonging to the discipline of cladistics. ... Bennettitales is an order of plants in the anthophyte clade that first appeared in the Triassic period and became extinct toward the end of the Cretaceous. ...


External links

Wikimedia Commons has media related to:
Gymnosperm


Pinguicula grandiflora commonly known as a Butterwort Example of a cross section of a stem [1] Botany is the scientific study of plant life. ... Ethnobotany is the study of the relationship between plants and people: Fromethno - study of people and botany - study of plants. ... Paleobotany (from the Greek words paleon = old and botanikos = of herbs) is the branch of paleontology dealing with the recovery and identification of plant remains from geological contexts, and their use in the reconstruction of past environments and the history of life. ... Plant anatomy or phytotomy is the general term for the study of the structure of plants. ... For the journal, see Ecology (journal). ... Evolutionary developmental biology (evo-devo) refers to the study of developmental programs and patterns from an evolutionary perspective. ... Plant anatomy or phytotomy is the general term for the study of the structure of plants. ... A germination rate experiment Plant physiology is a subdiscipline of botany concerned with the function, or physiology, of plants. ... Download high resolution version (454x765, 178 KB)Coconut Palm on Martinique. ... For other uses, see Plant (disambiguation). ... Plant evolution is an aspect of the study of biological evolution, involving predominantly the evolution of plants suited to live on land, the greening of the various land masses by the filling of their niches with land plants, and the diversification of the groups of land plants. ... For the programming language, see algae (programming language). ... The bryophytes are those embryophytes (land plants) that are non-vascular: they have tissues and enclosed reproductive systems, but they lack vascular tissue that circulates liquids. ... Classes Marattiopsida Osmundopsida Gleicheniopsida Pteridopsida A fern, or pteridophyte, is any one of a group of some twenty thousand species of plants classified in the Division Pteridophyta, formerly known as Filicophyta. ... Classes Magnoliopsida - Dicots Liliopsida - Monocots The flowering plants or angiosperms are the most widespread group of land plants. ... For other uses, see Flower (disambiguation). ... For other uses, see Fruit (disambiguation). ... Look up foliage in Wiktionary, the free dictionary. ... Tunica-Corpus model of the apical meristem. ... For other uses, see Root (disambiguation). ... Stem showing internode and nodes plus leaf petiole and new stem rising from node. ... Stoma of a leaf under a microscope. ... Cross section of celery stalk, showing vascular bundles, which include both phloem and xylem. ... For other uses, see Wood (disambiguation). ... Plant cell structure Plant cells are eukaryotic cells that differ in several key respects from the cells of other eukaryotic organisms. ... Plant cells separated by transparent cell walls. ... Chlorophyll is a green pigment found in most plants, algae, and cyanobacteria. ... Chloroplasts are organelles found in plant cells and eukaryotic algae that conduct photosynthesis. ... Photosynthesis splits water to liberate O2 and fixes CO2 into sugar The leaf is the primary site of photosynthesis in plants. ... Plant hormones (also known as plant growth regulators (PGRs) and phytohormones) are chemicals that regulate a plants growth. ... Plant cells with visible chloroplasts. ... Transpiration is the evaporation of excess water from aerial parts and of plants, especially leaves but also stems, flowers and fruits. ... Sporic or diplohaplontic life cycle. ... In plants that undergo alternation of generations, a gametophyte is the structure, or phase of life, that contains only half of the total complement of chromosomes: The sporophyte produces spores, in a process called meiosis. ... Close-up of an Echinopsis spachiana flower, showing both carpels and stamen, making it a complete flower. ... SEM image of pollen grains from a variety of common plants: sunflower (Helianthus annuus), morning glory (Ipomoea purpurea), prairie hollyhock (Sidalcea malviflora), oriental lily (Lilium auratum), evening primrose (Oenothera fruticosa), and castor bean (Ricinus communis). ... Carpenter bee with pollen collected from Night-blooming cereus Pollination is an important step in the reproduction of seed plants: the transfer of pollen grains (containing the male gametes, sperm) to the plant carpel of flowering plants, the structure that contains the ovule (which in turn houses the female gamete... A ripe red jalapeño cut open to show the seeds For other uses, see Seed (disambiguation). ... This article or section is in need of attention from an expert on the subject. ... Young sporophytes of the common moss Tortula muralis. ... Plant taxonomy is the science that finds, describes, classifies and names plants. ... A botanical name is a formal name conforming to the ICBN. As with its zoological and bacterial equivalents it may also be called a scientific name. Botanical names may be in one part (genus and above), two parts (species) or three parts (below the rank of species). ... Botanical nomenclature Plants are given formal names, governed by the ICBN. Within the limits set by the ICBN there is a separate set of rules, the ICNCP, for those plants in cultivation that require separate recognition, so-called cultivars. ... Studying a plant sample in the Herbarium In botany, a herbarium is a collection of preserved plant specimens. ... The International Association for Plant Taxonomy (IAPT) is devoted to plant systematics, taxonomy and nomenclature. ... The International Code of Botanical Nomenclature (ICBN) is the set of rules that governs plant nomenclature, i. ... Writing the Species Plantarum was one of Carolus Linnaeus two great contributions to the Scientific community. ...

  Results from FactBites:
 
The Gymnosperm Database: Home Page (1355 words)
Welcome to the Gymnosperm Database, the web's premier source of information on conifers and their allies.
For instance, it includes pages on the gymnosperms of Australia, the oldest trees in the world, and accounts of some of my field excursions.
The Gymnosperm Database was established as an online entity in the summer of 1997 and has since grown steadily, getting its own URL (Conifers.org) in the summer of 1999.
In this experiment, the effects of temperature on rate of photosynthesis in gymnosperms and angiosperms was studied ... (942 words)
Since gymnosperm needles remain green and attached to their tree branches in the winter time while angiosperm leaves turn brown, die and fall off of the branches, it was hypothesized that gymnosperms exhibit significantly higher rates of photosynthesis in colder climates than do angiosperms.
In support of the hypothesis, however, the mean rates of photosynthesis for the angiosperm and gymnosperm in the cold climate (which were -.3921 and -2.327 ppm/min/g, respectively) were indeed found to be significantly different; the gymnosperm rate of photosynthesis was significantly greater in cold climate than that of the angiosperm with a p-value of 0.0490.
Perhaps the reason that the gymnosperms maintain their green color in the winter is because of the possibility that they may go dormant in the winter time to conserve energy, much like hibernation; the green color is just the pigment being stored in the plant.
  More results at FactBites »

 
 

COMMENTARY     


Share your thoughts, questions and commentary here
Your name
Your comments

Want to know more?
Search encyclopedia, statistics and forums:

 


Press Releases |  Feeds | Contact
The Wikipedia article included on this page is licensed under the GFDL.
Images may be subject to relevant owners' copyright.
All other elements are (c) copyright NationMaster.com 2003-5. All Rights Reserved.
Usage implies agreement with terms, 1022, m