Bolivarian Republic of Venezuela
Ministry of Popular Power for Education IUP “Santiago Mariño” Extentionmerida teacher Aracelis Torres
Student: Alfredo Contreras
INTRODUCTION Biology is a branch of science that studies living things , classification, characteristics , development and other issues of great importance . For centuries , man's constant study has allowed us to distinguish the various life forms that exist on our planet , behavior and development. However, it is not so easy to find the classification of a particular being , you should get to know their characteristics, behavior , lifestyle etc . Therefore, in this paper we try to explain in a clear and precise everything related to the kingdom Plantae or plant . For this we use information sources such as encyclopedias and internet web pages to achieve the purpose of the investigation. Vegetable or Plant , any member of the plant kingdom or realm Plants ( Plantae ) consists of about 260,000 known species of mosses, liverworts , ferns , herbaceous and woody plants , shrubs , trees and other life forms that cover the earth and live
well in water. The size and complexity of the plant are highly variable , this realm includes from small nonvascular mosses , which need to be in direct contact with the water, to giant sequoias the largest living organisms capable, with its root system , to raise water and compounds minerals to over a hundred feet high. Man uses directly only a small percentage of the plants to get food , shelter , fibers and medicines. At the top of the list are rice , wheat , maize , pulses , cotton , conifers and snuff , species that depend on the economy of entire nations . But there are more important for mankind the indirect benefits derived from whole plant kingdom , which has more than 3000 million years performing photosynthesis. The plants have left us fossil fuels that power , and throughout its long history have provided enough oxygen to the atmosphere keep the evolution of higher animals . Currently, global biomass is formed in an overwhelming proportion by plants, which not only provide the basis for all food chains , but also modified climates , and create and hold the soil , thus transforming it into other habitable otherwise be masses of stones and sand.
THE KINGDOM PLANTAE Real plants or embri贸fitos ( Kingdom Plantae ) are multicellular organisms, autotrophic , have cells with walls of cellulose containing chlorophyll a and b carotenoids as accessory pigments ; store starch , have a life cycle or diplobi贸ntico esp贸rico with alternation of generations heteromorphic : gametophyte haploid (n ) and the diploid sporophyte (2n) ; gametangios surrounded by a sterile cell layer ( the sterile jacket ) are present or absent , are og谩micas , have mobile or non-mobile sperm ( the other cells are not mobile ) produce an embryo There are so many different plants around the world, although it is recognized that they all belong to the kingdom plantae (with some exceptions ) , researchers still do not get full agreement of how to classify , however , a classification that is used which is currently held Cronquist in 1969. The kingdom plantae can be grouped into 4 main groups can be separated into several divisions :
Bryophytes . Pteridophytes. Gymnosperms . Angiosperms .
DIVISION bryophyte This division includes the so called bryophytes , these are the liverworts , mosses and hornworts . They are small plants that have colonized the terrestrial environment, although abundant mainly in places with high humidity , since water needed to carry out their reproductive cycle . Another feature is that bryophytes show a heteromorphic alternation of generations , which is haploid gametophyte generation is dominant over the diploid sporophyte is developed on the gametophyte . According to the morphology of the gametophyte are two types of bryophytes : Talosos bryophytes are hornworts and some liver talo its gametophyte is flattened which is fixed to a substrate by rizoides (small filament powerless absorbent ) . Leafy bryophytes are mosses and liverworts majority of these have a caulidio gametophytes (shaft) rizoides also fixed to the substrate, also along the caulidio have a small leaves or Filidios .
Another feature of bryophytes is not having a conductive fabric such as xylem or phloem of vascular plants , some have no conducting cells and use the whole surface to absorb water and nutrients, and others have a more specific conducting cells .
DIVISION Pteridophyta In this taxon are included all vascular cryptogams , ie , ferns and other related plants . The sexual cycle is characterized by an alternation of generations sporophyte dominance on the gametophyte . The sporophyte is vascularized , since it is provided with xylem , phloem and other elements necessary for the transport of water and other substances throughout the plant. Can distinguish the sporophyte the root ( at most evolved ferns ) , a stem that is more or less developed but generally reduced to an underground rhizome , and some leaves or fronds having different sizes depending on the species . On the underside of the fronds or on its edge are arranged sporangia spore forming , sometimes on the same floor are two types of leaves : trof贸filas that are sterile and are used to capture energy and perform photosynthesis , and leaves sporophylls that are sporangia bearing fertile .
The sporangia are usually grouped in sori that may be bare or covered by a membranous or indusia formations formed from the leaves. Inside are sporangia spores are released to the outside for germination to occur this fact forms a very small gamet贸fito called protalo , which is usually a sheet of less than 2 centimeters rizoides bonded to the substrate by . In gametophytes are both archegonia and antheridia containing the osfera and anterozoides respectively. Fertilization must occur in the presence of water or in a rainy season since anterozoides , which are flagellated , swimming to reach the archegonium to merge with osfera . At this time there is a diploid zygote will result in a new Sporophyte .
The kingdom plantae is one of the seven kingdoms into which living things are classified and also one of the most complex because of their age and the great diversity of representatives that exist throughout the planet . It has characteristics that differentiate them from the other kingdoms fully , without doubt a mistake , you can set whether or not a being belongs to the kingdom plantae, studying its characteristics and then establishing similarities with the general characteristics of an individual belonging to this kingdom . It was learned plantae kingdom classification , characteristics, class orders and families , each with its own characteristics. It is very important to study this realm as we are in constant contact with its members and their specific know we can contribute to its development.
Research are expected to have covered the proposed objective and serve as a theoretical basis in subsequent works .