Shopping on line can be easy, simple and save you lots of money. It can also take a lot of your time, frustrate you, and result in unwanted purchases. Now the same can be said for regular high street shopping, but with the vast opportunity presented by the Internet it will pay you to spend a few minutes reading this and understanding how to better optimize your Plant shopping experience:

1. Compare - without doubt the biggest advantage that the Plant offers shoppers today is the ability to compare thousands of Plant at a time. This is a great thing, but not necessarily all the time! Too much can be daunting at times so take advantage of the great comparison sites and where possible let them do the hard work for you.

2. Research - if it has been said it will be on the internet. Ignorance is no longer a justifiable reason for buying the wrong thing. Take the time to research in detail everything that you could possible want to know about

3. Testimonials - don't know anybody that has bought a Plant? Wrong! If the Plant is good the internet will let you know. Use the Internet as a friend and get testimonials before you buy.

4. Questions - Got a question about Plant then search the Forums, FAQ's, Blogs etc. Don't be afraid to ask .....

5. Reputation - Never heard of the company selling Plant? Don't worry, no reason why you should know every company in the world, but you know someone that does! Use the internet to find out what people are saying about Plant and build up a picture of their reputation for sales, returns, customer service, delivery etc.

6. Returns - still worried that even after all of the above your Plant wont be what you want? Check out the returns policy. There is so much competition now that someone, somewhere is bound to offer the terms that you are comfortable with.

7. Feedback - happy with your Plant then let people know, after all you are depending on others people input in your buying decision, so why not give a little back.

8. Security - check for the yellow padlock on the Plant site before you buy, and the s after http:/ /i.e. https:// = a secure site

9. Contact - got a question about Plant, or want to leave a comment then check out the sites contact page. Reputable companies have them and respond.

10. Payment - ready to pay for your Plant, then use your credit card or PayPal! Be aware of companies that don't accept them, there may be genuine reasons but given the huge amount of choice you have when buying online there is no reason at all not to buy via credit card or PayPal.

{{Taxobox| color = lightgreen| name = Plants| fossil_range = Cambrian to recent, but #Fossils| image = Plants diversity.jpg| image_width = 250px| image_caption =| domain = Eukaryote| unranked_regnum = Archaeplastida, 1866| subdivision_ranks = Divisions| subdivision =[Green algae Embryophyte (embryophytes) † Nematophytes-->

Plants are a major group of life forms and include familiar organisms such as trees, herbs, bushes, grasses, vines, ferns, mosses, and green algae. About 350,000 species of plants, defined as seed plants, bryophytes, ferns and fern allies, are estimated to exist currently. As of 2004, some 287,655 species had been identified, of which 258,650 are flowering and 15,000 bryophytes. Green plants, sometimes called metaphytes, obtain most of their energy from Electromagnetic radiation via a process called photosynthesis.

Definition Aristotle divided all living things between plants (which generally do not move), and animals (which often are mobile to catch their food). In Carolus Linnaeus' system, these became the kingdom (biology) Vegetabilia (later Metaphyta or Plantae) and Animalia (also called Metazoa). Since then, it has become clear that the Plantae as originally defined included several unrelated groups, and the fungus and several groups of algae were removed to new kingdoms. However, these are still often considered plants in many contexts, both technical and popular. Indeed, an attempt to perfectly match "plant" with a single taxon is problematic, because for most people the term "plant" is only vaguely related to the Phylogenetics concepts on which modern taxonomy and systematics are based.

When the name Plantae is applied to a specific taxon, it is usually referring to one of three concepts. From smallest to largest in inclusiveness, these three groupings are:

Informally, other creatures that carry out photosynthesis are called plants as well, but they do not constitute a formal taxon and represent species that are not closely related to true plants. There are around about 375,000 species (types) of plants, and each year more are found and described by science.

Algae from Ernst Haeckel's Kunstformen der Natur, 1904.

The algae comprise several different groups of organisms that produce energy through photosynthesis. However, most are not classified within the Kingdom Plantae but in the Kingdom Protista. Most conspicuous are the seaweeds, multicellular algae that may roughly resemble terrestrial plants, but are classified among the green alga, red alga, and brown algae. These and other algal groups also include various single-celled organisms.

The embryophytes developed from green algae (Chlorophyta); the two groups are collectively referred to as the green plants or Viridiplantae. The Kingdom Plantae is often taken to mean this monophyletic grouping. With a few exceptions among the green algae, all such forms have cell walls containing cellulose and chloroplasts containing chlorophylls a and b, and store food in the form of starch. They undergo closed mitosis without centrioles, and typically have mitochondrion with flat cristae.

The chloroplasts of green plants are surrounded by two membranes, suggesting they originated directly from endosymbiotic cyanobacteria. The same is true of the red algae, and the two groups are generally believed to have a common origin (see Archaeplastida). In contrast, most other algae have chloroplasts with three or four membranes. They are not close relatives of the green plants, presumably in origin acquiring chloroplasts separately from ingested or symbiotic green and red algae.

Fungi Fungus are no longer considered to be plants, though they were previously included in the plant kingdom. Unlike embryophytes and algae, fungi are not photosynthetic, but are saprotrophs: obtaining food by breaking down and absorbing surrounding materials. Fungi are not plants, but were historically treated as closely related to plants, and were considered to be in the purview of botanists. It has long been recognized that fungi are evolutionarily closer to animals than to plants, but they still are covered more in depth in introductory botany courses and are not necessarily touched upon in introductory zoology courses. Most fungi are formed by microscopic structures called hyphae, which may or may not be divided into cells but contain eukaryotic cell nucleus. Fruiting bodies, of which mushrooms are most familiar, are the reproductive structures of fungi. They are not related to any of the photosynthetic groups, but are close relatives of animals. Therefore, the fungi are in a kingdom of their own.

Diversity About 350,000 species of plants, defined as seed plants, bryophytes, ferns and fern allies, are estimated to exist currently. As of 2004, some 287,655 species had been identified, of which 258,650 are flowering plants, 16,000 bryophytes, 11,000 ferns and 8,000 green algae.

{]| Chlorophyta] (chlorophytes)| align="right" | 3,800 Van den Hoek, C., D. G. Mann, & H. M. Jahns, 1995. Algae:An Introduction to Phycology. pages 343, 350, 392, 413, 425, 439, & 448 (Cambridge: Cambridge University Press). ISBN 0-521-30419-9|-| Charophyta] (desmids & charophytes)]s| Marchantiophyta]| align="left" | hornworts| align="right" | 100 - 200 Schuster, Rudolf M., The Hepaticae and Anthocerotae of North America, volume VI, pages 712-713. (Chicago: Field Museum of Natural History, 1992). ISBN 0-914-86821-7.|-| Moss| align="left" | mosses| align="right" | 10,000 Buck, William R. & Bernard Goffinet, 2000. "Morphology and classification of mosses", page 71 in A. Jonathan Shaw & Bernard Goffinet (Eds.), Bryophyte Biology. (Cambridge: Cambridge University Press). ISBN 0-521-66097-1|-| rowspan=2 style="background:lightgray" valign="top" | Pteridophytes]| align="left" | club mosses| align="right" | 1,200 Raven, Peter H., Ray F. Evert, & Susan E. Eichhorn, 2005. Biology of Plants, 7th edition. (New York: W. H. Freeman and Company). ISBN 0-7167-1007-2.|-| Pteridophyta]s| Cycadophyta]| align="left" | ginkgo| align="right" | 1 Taylor, Thomas N. & Edith L. Taylor, 1993. The Biology and Evolution of Fossil Plants, page 636. (New Jersey: Prentice-Hall). ISBN 0-13-651589-4.|-| Pinophyta]| align="left" | gnetophytes| align="right" | 70 |-| Flowering plant| align="left" | flowering plants| align="right" | 258,650 lnternational Union for Conservation of Nature and Natural Resources, 2006. IUCN Red List of Threatened Species:Summary Statistics|}

Phylogeny A proposed phylogeny of the Plantae after Kenrick and CraneKenrick, Paul & Peter R. Crane. 1997. The Origin and Early Diversification of Land Plants: A Cladistic Study. (Washington, D.C.: Smithsonian Institution Press). ISBN 1-56098-730-8. is as follows, with modification to the Pteridophyta from Smith et al.Smith, Alan R., Kathleen M. Pryer, E. Schuettpelz, P. Korall, H. Schneider, & Paul G. Wolf. (2006). " A classification for extant ferns". Taxon 55(3): 705-731. The Prasinophyceae may be a paraphyletic basal group to all green plants.

{{clade (micromonads) |2={{clade |label1=Streptobionta |1={{clade |1={{clade |label1=[Embryophytes |1={{clade |1={{clade |label1=Stomatophytes |1={{clade |1={{clade |label1=Polysporangiates |1={{clade |1={{clade |label1=[Vascular plant |1={{clade |label1=Eutracheophytes |1={{clade |label1=Euphyllophytina |1={{clade |label1=Lignophytia |1={{clade |1='''[Spermatophyta''' (seed plants) |2=[Progymnospermophyta † --> |label2='''[Fern''' |2={{clade |1={{clade |1=[Pteridopsida (true ferns) |2=[Marattiopsida |3=[Equisetopsida (horsetails) |4=[Psilotopsida (whisk ferns & adders'-tongues) |5=[Cladoxylopsida † --> --> --> |label2=Lycophytina |2={{clade |1='''[Lycopodiophyta''' |2=[Zosterophyllophyta † --> --> |2=[Rhyniophyta † --> --> |2=''[Aglaophyton'' † |3=[Horneophytopsida † --> --> |2='''[Moss''' (mosses) |3='''[Anthocerotophyta''' (hornworts) --> --> |2='''[Marchantiophyta''' (liverworts) --> --> |2='''[Charophyta''' --> --> |3={{clade |label1='''[Chlorophyta''' |1={{clade |1={{clade |1=[Trebouxiophyceae (Pleurastrophyceae) |2=[Chlorophyceae --> |2=[Ulvophyceae --> --> --> -->

Embryophytes , a species of tree fern.Most familiar are the multicellular land plants, called embryophytes. They include the vascular plants, plants with full systems of leaf, Plant stem, and roots. They also include a few of their close relatives, often called bryophytes, of which mosses and Marchantiophyta are the most common.

All of these plants have eukaryote cells with cell walls composed of cellulose, and most obtain their energy through photosynthesis, using light and carbon dioxide to synthesize food. About three hundred plant species do not photosynthesize but are parasites on other species of photosynthetic plants. Plants are distinguished from green algae, which represent a mode of photosynthetic life similar to the kind modern plants are believed to have evolved from, by having specialized reproductive organs protected by non-reproductive tissues.

Bryophytes first appeared during the early Palaeozoic. They can only survive where moisture is available for significant periods, although some species are desiccation tolerant. Most species of bryophyte remain small throughout their life-cycle. This involves an alternation between two generations: a haploid stage, called the gametophyte, and a diploid stage, called the sporophyte. The sporophyte is short-lived and remains dependent on its parent gametophyte.

Vascular plants first appeared during the Silurian period, and by the Devonian had diversified and spread into many different land environments. They have a number of adaptations that allowed them to overcome the limitations of the bryophytes. These include a cuticle resistant to desiccation, and vascular tissues which transport water throughout the organism. In most the sporophyte acts as a separate individual, while the gametophyte remains small.

The first primitive seed plants, Pteridosperms (seed ferns) and Cordaites, both groups now extinct, appeared in the late Devonian and diversified through the Carboniferous, with further evolution through the Permian and Triassic periods. In these the gametophyte stage is completely reduced, and the sporophyte begins life inside an enclosure called a seed, which develops while on the parent plant, and with fertilisation by means of pollen grains. Whereas other vascular plants, such as ferns, reproduce by means of spores and so need moisture to develop, some seed plants can survive and reproduce in extremely arid conditions.

Early seed plants are referred to as gymnosperms (naked seeds), as the seed embryo is not enclosed in a protective structure at pollination, with the pollen landing directly on the embryo. Four surviving groups remain widespread now, particularly the conifers, which are dominant trees in several biomes. The angiosperms, comprising the flowering plants, were the last major group of plants to appear, emerging from within the gymnosperms during the Jurassic and diversifying rapidly during the Cretaceous. These differ in that the seed embryo (angiosperm) is enclosed, so the pollen has to grow a tube to penetrate the protective seed coat; they are the predominant group of flora in most biomes today.

Fossils .Plant fossils include roots, wood, leaves, seeds, fruit, pollen, spores, phytoliths, and amber (the fossilized resin produced by some plants). Fossil land plants are recorded in terrestrial, lacustrine, fluvial and nearshore marine sediments. Pollen, spores and algae (dinoflagellates and acritarchs) are used for dating sedimentary rock sequences. The remains of fossil plants are not as common as fossil animals, although plant fossils are locally abundant in many regions worldwide.

The earliest fossils clearly assignable to Kingdom Plantae are fossil green algae from the Cambrian. These fossils resemble calcified multicellular members of the Dasycladales. Earlier Precambrian fossils are known which resemble single-cell green algae, but definitive identity with that group of algae is uncertain.

The oldest known trace fossils of embryophytes date from the Ordovician, though such fossils are fragmentary. By the Silurian, fossils of whole plants are preserved, including the lycophyte Baragwanathia longifolia. From the Devonian, detailed fossils of rhyniophytes have been found. Early fossils of these ancient plants show the individual cells within the plant tissue. The Devonian period also saw the evolution of what many believe to be the first modern tree, Archaeopteris. This fern-like tree combined a woody trunk with the fronds of a fern, but produced no seeds.

The Coal Measures are a major source of Palaeozoic plant fossils, with many groups of plants in existence at this time. The spoil heaps of coal mines are the best places to collect; coal itself is the remains of fossilised plants, though structural detail of the plant fossils is rarely visible in coal. In the Fossil Forest at Victoria Park in Glasgow, Scotland, the stumps of Lepidodendron trees are found in their original growth positions.

The fossilized remains of conifer and angiosperm roots, stems and branches may be locally abundant in lake and inshore sedimentary rocks from the Mesozoic and Caenozoic eras. Coast Redwood and its allies, magnolia, oak, and Arecaceae are often found.

Petrified wood is common in some parts of the world, and is most frequently found in arid or desert areas where it is more readily exposed by erosion. Petrified wood is often heavily silicified (the organic material replaced by silicon dioxide), and the impregnated tissue is often preserved in fine detail. Such specimens may be cut and polished using lapidary equipment. Fossil forests of petrified wood have been found in all continents.

Fossils of seed ferns such as Glossopteris are widely distributed throughout several continents of the southern hemisphere, a fact that gave support to Alfred Wegener's early ideas regarding Continental drift theory.

Life processes Growth Most of the solid material in a plant is taken from the atmosphere. Through a process known as photosynthesis, plants use the energy in sunlight to convert carbon dioxide from the atmosphere into simple sugars. These sugars are then used as building blocks and form the main structural component of the plant. Plants rely on soil primarily for support and water (in quantitative terms), but also obtain nitrogen, phosphorus and other crucial elemental nutrients. For the majority of plants to grow successfully they also require oxygen in the atmosphere (for respiration in the dark) and oxygen around their roots. However, a few specialized vascular plants, such as Mangroves, can grow with their roots in anoxic conditions.

is the primary site of photosynthesis in plants.

Factors affecting growth The genotype of a plant affects its growth, for example selected varieties of wheat grow rapidly, maturing within 110 days, whereas others, in the same environmental conditions, grow more slowly and mature within 155 days.Robbins, W.W., Weier, T.E., et al, Botany:Plant Science, 3rd edition , Wiley International, New York, 1965.

Growth is also determined by environmental factors, such as temperature, available water, available light, and available nutrients in the soil. Any change in the availability of these external conditions will be reflected in the plants growth.

Biotic factors (living organisms) also affect plant growth.



Simple plants like algae may have short life spans as individuals, but their populations are commonly seasonal. Other plants may be organized according to their seasonal growth pattern:

Among the vascular plants, perennials include both evergreens that keep their leaves the entire year, and deciduous plants which lose their leaves for some part. In temperate and boreal climates, they generally lose their leaves during the winter; many tropical plants lose their leaves during the dry season.

The growth rate of plants is extremely variable. Some mosses grow less than 0.001 mm/h, while most trees grow 0.025-0.250 mm/h. Some climbing species, such as kudzu, which do not need to produce thick supportive tissue, may grow up to 12.5 mm/h.

Plants protect themselves from frost and dehydration stress with antifreeze proteins, Heat shock protein and sugars (sucrose is common). LEA (Late Embryogenesis Abundant) protein expression is induced by stresses and protects other proteins from aggregation as a result of desiccation and freezing.

Internal distribution elements in the shoot of a fig tree (Ficus alba): crushed in hydrochloric acid, between slides and cover slips.Nutrients and water from the soil and the organic compound produces in leaves are distributed to specific areas in the plant through the xylem and phloem. The xylem draws water and nutrients up from the roots to the upper sections of the plant's body, and the phloem conducts other materials, such as the glucose produced during photosynthesis, which gives the plant energy to keep growing and seeding.

The xylem consists of tracheids, which are dead hard-walled cells arranged to form tiny tubes to function in water transport. A tracheid cell wall usually contains the polymer lignin. The phloem however consists of living cells called sieve-tube members. Between the sieve-tube members are sieve plates, which have pores to allow molecules to pass through. Sieve-tube members lack such organs as nuclei or ribosomes, but cells next to them, the companion cells, function to keep the sieve-tube members alive.

Movement of nutrients, water, sugars and waste is effected by transpiration, conduction and absorption.

Transpiration The most abundant compound in most plants is water, serving a large role in the various processes taking place. Transpiration is the main process a plant can call upon to move compounds within its tissues. The basic minerals and nutrients a plant is composed of remain, generally, within the plant. Water, however, is constantly being lost from the plant through its metabolic and photosynthetic processes to the atmosphere.

Water is transpired from the plants leaves via stomata, carried there via leaf veins and vascular bundles within the plants cambium layer. The movement of water out of the leaf stomata creates, when the leaves are considered collectively, a transpiration pull. The pull is created through water surface tension within the plant cells. The draw of water upwards is assisted by the movement of water into the roots via osmosis. This process also assists the plant in absorbing nutrients from the soil as soluble salts, a process known as absorption.

Absorption Xylem cells move water and nutrient solutions upwards towards other plant organs from the roots and fine root hairs. Living roots cells actively absorb water in the absence of transpiration pull via osmosis creating root pressure. There are times when plants do not have transpiration pull, usually due to lack of light or other environmental elements. Water in the plant tissues may move to the roots to assist in passive absorption.

Conduction Xylem and phloem tissues are involved in the conduction processes within plants. The movement of foods throughout the plant takes place mainly in the phloem. Plant conduction (food movement) is from an area of high food content, place of manufacture (photosynthesis) or storage, to a place of food utilisation, or from a point of manufacture to storage tissues. Mineral salts are translocated in the xylem tissues.

Ecology The photosynthesis conducted by land plants and algae is the ultimate source of energy and organic material in nearly all ecosystems. Photosynthesis radically changed the composition of the early Earth's atmosphere, which as a result is now 21% oxygen. Animals and most other organisms are Aerobic organism, relying on oxygen; those that do not are confined to relatively rare anaerobic environments. Plants are the Autotroph in most terrestrial ecosystems and form the basis of the food web in those ecosystems. Many animals rely on plants for shelter as well as oxygen and food.

Land plants are key components of the water cycle and several other biogeochemical cycles. Some plants have coevolved with nitrogen fixation bacteria, making plants an important part of the nitrogen cycle. Plant roots play an essential role in soil development and prevention of soil erosion.

Distribution Plants are distributed worldwide in varying numbers. While they inhabit a multitude of biomes and ecoregions, few can be found beyond the tundras at the northernmost regions of continental shelf. At the southern extremes, plants have adapted tenaciously to the prevailing conditions. (See Antarctic flora.)

Plants are often the dominant physical and structural component of habitats where they occur. Many of the Earth's biomes are named for the type of vegetation because plants are the dominant organisms in those biomes, such as grasslands and forests.

Ecological relationships , a species of carnivorous plant.Numerous animals have coevolved with plants. Many animals pollinate flowers in exchange for food in the form of pollen or nectar. Many animals biological dispersal, often by eating fruit and passing the seeds in their feces. Myrmecophytes are plants that have coevolved with ants. The plant provides a home, and sometimes food, for the ants. In exchange, the ants defend the plant from herbivores and sometimes competing plants. Ant wastes provide organic fertilizer.

The majority of plant species have various kinds of fungi associated with their root systems in a kind of mutualistic symbiosis known as mycorrhiza. The fungi help the plants gain water and mineral nutrients from the soil, while the plant gives the fungi carbohydrates manufactured in photosynthesis. Some plants serve as homes for endophyte fungi that protect the plant from herbivores by producing toxins. The fungal endophyte, Neotyphodium coenophialum, in tall fescue (Festuca arundinacea) does tremendous economic damage to the cattle industry in the U.S.

Various forms of parasitism are also fairly common among plants, from the semi-parasitic mistletoe that merely takes some nutrients from its host, but still has photosynthetic leaves, to the fully parasitic broomrape and toothwort that acquire all their nutrients through connections to the roots of other plants, so have no chlorophyll. Some plants, known as myco-heterotrophs, parasitize mycorrhizal fungi, and hence act as epiparasites on other plants.

Many plants are epiphytes, meaning they grow on other plants, usually trees, without parasitizing them. Epiphytes may indirectly harm their host plant by intercepting mineral nutrients and light that the host would otherwise receive. The weight of large numbers of epiphytes may break tree limbs. Many orchids, bromeliads, ferns and mosses often grow as epiphytes. Bromeliad epiphytes accumulate water in leaf axils to form phytotelmata, complex aquatic food webs.Bromeliad Phytotelmata

A few plants are carnivorous plant, such as the Venus Flytrap and sundew. They trap small animals and digest them to obtain mineral nutrients, especially nitrogen.

Importance plant. Potatoes spread to the rest of the world after European contact with the Americas in the late 1400s and early 1500s and have since become an important field crop. in storage for later processing at a sawmill. branch showing 27 annual growth rings, pale sapwood and dark heartwood, and pith (centre dark spot). The dark radial lines are small knots.The study of plant uses by people is termed economic botany or ethnobotany. They are often used as synonyms but some consider economic botany to focus mainly on uses of modern cultivated plants, while ethnobotany studies uses of indigenous plants by native peoples. Human cultivation of plants is part of agriculture, which is the basis of human civilization. Plant agriculture is subdivided into agronomy, horticulture and forestry.

Food Virtually all human nutrition depends on land plants directly or indirectly. Much of human nutrition depends on cereals, especially maize, wheat and rice or other staple crops such as potato, cassava, and legumes. Other parts from plants that are eaten include fruits, vegetables, nut (fruit), herbs, spices and flowers. Beverages from plants include coffee, tea, wine, beer and alcohol. Sugar is obtained mainly from sugar cane and sugar beet. Cooking oils and margarine come from corn, soybean, canola, safflower, sunflower, olive and others. Food additives include gum arabic, guar gum, locust bean gum, starch and pectin.

Nonfood products Wood is used for buildings, furniture, paper, cardboard, musical instruments and sports equipment. Cloth is often made from cotton, flax or synthetic fibers derived from cellulose, such as rayon and acetate. Renewable fuels from plants include firewood, peat and many other biofuels. Coal and petroleum are fossil fuels derived from plants. Medicines derived from plants include aspirin, taxol, morphine, quinine, reserpine, colchicine, digitalis and vincristine. There are hundreds of herbal supplements such as ginkgo, Echinacea, feverfew, and Saint John's wort. Pesticides derived from plants include nicotine, rotenone, strychnine and pyrethrins. Drugs obtained from plants include opium, cocaine and cannabis (drug). Poisons from plants include ricin, Conium and curare. Plants are the source of many natural products such as fibers, essential oils, dyes, pigments, waxes, tannins, latex, gums, resins, alkaloids, amber and cork. Products derived from plants include soaps, paints, shampoos, perfumes, cosmetics, turpentine, rubber, varnish, lubricants, linoleum, plastics, inks, chewing gum and hemp rope. Plants are also a primary source of basic chemicals for the industrial synthesis of a vast array of organic chemicals. These chemicals are used in a vast variety of studies and experiments.

Aesthetic uses Thousands of plant species are cultivated to beautify the human environment as well as to provide shade, modify temperatures, reduce windspeed, abate noise, provide privacy and prevent soil erosion. People use cut flowers, dried flowers and house plants indoors. Outdoors, they use lawngrasses, shade trees, ornamental trees, shrubs, vines, herbaceous perennials and bedding plants. Images of plants are often used in art, architecture, humor, Language of flowers and photography and on textiles, money, stamps, flags and coats of arms. Living plant art forms include topiary, bonsai, ikebana and espalier. Ornamental plants have sometimes changed the course of history, as in tulipomania. Plants are the basis of a multi-billion dollar per year tourism industry which includes travel to arboretums, botanical gardens, garden tourism, national parks, tulip festivals, rainforests, forests with colorful autumn leaves and the National Cherry Blossom Festival. Venus flytrap, sensitive plant and resurrection plant are examples of plants sold as novelties.

Scientific and cultural uses Tree rings are an important method of dating in archeology and serve as a record of past climates. Basic biological research has often been done with plants, such as the pea plants used to derive Gregor Mendel's laws of genetics. Space stations or space colonies may one day rely on plants for Controlled Ecological Life Support System. Plants are used as National emblem and state emblems, including List of U.S. state trees and state flowers. Ancient trees are revered and many are List of famous trees. Numerous world records are held by plants. Plants are often used as memorials, gifts and to mark special occasions such as births, deaths, weddings and holidays. Plants figure prominently in Trees in mythology, religion and List of fictional plants. The field of ethnobotany studies plant use by indigenous cultures which helps to conserve endangered species as well as discover new herbalism. Gardening is the most popular leisure activity in the U.S. Working with plants or horticulture therapy is beneficial for rehabilitating people with disabilities. Certain plants contain psychotropic chemicals which are extracted and ingested, including tobacco, Cannabis (drug) (marijuana), and opium.

Negative effects Weeds are plants that grow where people do not want them. People have spread plants beyond their native ranges and some of these introduced plants become invasive species, damaging existing ecosystems by displacing native species. Invasive plants cause billions of dollars in crop losses annually by displacing crop plants, they increase the cost of production and the use of chemical means to control them effects the environment.

Plants may cause harm to people. Plants that produce windblown pollen invoke allergic reactions in people who suffer from hay fever. A wide variety of plants are List of poisonous plants. Several plants cause skin irritations when touched, such as poison ivy. Certain plants contain psychotropic secondary metabolite, which are extracted and ingested or smoked, including tobacco, cannabis (marijuana), cocaine and opium, causing damage to health or even death. Both illegal and legal drugs derived from plants have negative effects on the economy, effecting worker productivity and law enforcement costs. Some plants cause allergic reactions in people and animals when ingested, while other plants cause food intolerances that negatively effect health.

See also

References Further reading General:

Species estimates and counts:

External links

Botanical and vegetation databases

{{Taxobox| color = lightgreen| name = Plants| fossil_range = Cambrian to recent, but #Fossils| image = Plants diversity.jpg| image_width = 250px| image_caption =| domain = Eukaryote| unranked_regnum = Archaeplastida, 1866| subdivision_ranks = Divisions| subdivision =[Green algae Embryophyte (embryophytes) † Nematophytes-->

Plants are a major group of life forms and include familiar organisms such as trees, herbs, bushes, grasses, vines, ferns, mosses, and green algae. About 350,000 species of plants, defined as seed plants, bryophytes, ferns and fern allies, are estimated to exist currently. As of 2004, some 287,655 species had been identified, of which 258,650 are flowering and 15,000 bryophytes. Green plants, sometimes called metaphytes, obtain most of their energy from Electromagnetic radiation via a process called photosynthesis.

Definition Aristotle divided all living things between plants (which generally do not move), and animals (which often are mobile to catch their food). In Carolus Linnaeus' system, these became the kingdom (biology) Vegetabilia (later Metaphyta or Plantae) and Animalia (also called Metazoa). Since then, it has become clear that the Plantae as originally defined included several unrelated groups, and the fungus and several groups of algae were removed to new kingdoms. However, these are still often considered plants in many contexts, both technical and popular. Indeed, an attempt to perfectly match "plant" with a single taxon is problematic, because for most people the term "plant" is only vaguely related to the Phylogenetics concepts on which modern taxonomy and systematics are based.

When the name Plantae is applied to a specific taxon, it is usually referring to one of three concepts. From smallest to largest in inclusiveness, these three groupings are:

Informally, other creatures that carry out photosynthesis are called plants as well, but they do not constitute a formal taxon and represent species that are not closely related to true plants. There are around about 375,000 species (types) of plants, and each year more are found and described by science.

Algae from Ernst Haeckel's Kunstformen der Natur, 1904.

The algae comprise several different groups of organisms that produce energy through photosynthesis. However, most are not classified within the Kingdom Plantae but in the Kingdom Protista. Most conspicuous are the seaweeds, multicellular algae that may roughly resemble terrestrial plants, but are classified among the green alga, red alga, and brown algae. These and other algal groups also include various single-celled organisms.

The embryophytes developed from green algae (Chlorophyta); the two groups are collectively referred to as the green plants or Viridiplantae. The Kingdom Plantae is often taken to mean this monophyletic grouping. With a few exceptions among the green algae, all such forms have cell walls containing cellulose and chloroplasts containing chlorophylls a and b, and store food in the form of starch. They undergo closed mitosis without centrioles, and typically have mitochondrion with flat cristae.

The chloroplasts of green plants are surrounded by two membranes, suggesting they originated directly from endosymbiotic cyanobacteria. The same is true of the red algae, and the two groups are generally believed to have a common origin (see Archaeplastida). In contrast, most other algae have chloroplasts with three or four membranes. They are not close relatives of the green plants, presumably in origin acquiring chloroplasts separately from ingested or symbiotic green and red algae.

Fungi Fungus are no longer considered to be plants, though they were previously included in the plant kingdom. Unlike embryophytes and algae, fungi are not photosynthetic, but are saprotrophs: obtaining food by breaking down and absorbing surrounding materials. Fungi are not plants, but were historically treated as closely related to plants, and were considered to be in the purview of botanists. It has long been recognized that fungi are evolutionarily closer to animals than to plants, but they still are covered more in depth in introductory botany courses and are not necessarily touched upon in introductory zoology courses. Most fungi are formed by microscopic structures called hyphae, which may or may not be divided into cells but contain eukaryotic cell nucleus. Fruiting bodies, of which mushrooms are most familiar, are the reproductive structures of fungi. They are not related to any of the photosynthetic groups, but are close relatives of animals. Therefore, the fungi are in a kingdom of their own.

Diversity About 350,000 species of plants, defined as seed plants, bryophytes, ferns and fern allies, are estimated to exist currently. As of 2004, some 287,655 species had been identified, of which 258,650 are flowering plants, 16,000 bryophytes, 11,000 ferns and 8,000 green algae.

{]| Chlorophyta] (chlorophytes)| align="right" | 3,800 Van den Hoek, C., D. G. Mann, & H. M. Jahns, 1995. Algae:An Introduction to Phycology. pages 343, 350, 392, 413, 425, 439, & 448 (Cambridge: Cambridge University Press). ISBN 0-521-30419-9|-| Charophyta] (desmids & charophytes)]s| Marchantiophyta]| align="left" | hornworts| align="right" | 100 - 200 Schuster, Rudolf M., The Hepaticae and Anthocerotae of North America, volume VI, pages 712-713. (Chicago: Field Museum of Natural History, 1992). ISBN 0-914-86821-7.|-| Moss| align="left" | mosses| align="right" | 10,000 Buck, William R. & Bernard Goffinet, 2000. "Morphology and classification of mosses", page 71 in A. Jonathan Shaw & Bernard Goffinet (Eds.), Bryophyte Biology. (Cambridge: Cambridge University Press). ISBN 0-521-66097-1|-| rowspan=2 style="background:lightgray" valign="top" | Pteridophytes]| align="left" | club mosses| align="right" | 1,200 Raven, Peter H., Ray F. Evert, & Susan E. Eichhorn, 2005. Biology of Plants, 7th edition. (New York: W. H. Freeman and Company). ISBN 0-7167-1007-2.|-| Pteridophyta]s| Cycadophyta]| align="left" | ginkgo| align="right" | 1 Taylor, Thomas N. & Edith L. Taylor, 1993. The Biology and Evolution of Fossil Plants, page 636. (New Jersey: Prentice-Hall). ISBN 0-13-651589-4.|-| Pinophyta]| align="left" | gnetophytes| align="right" | 70 |-| Flowering plant| align="left" | flowering plants| align="right" | 258,650 lnternational Union for Conservation of Nature and Natural Resources, 2006. IUCN Red List of Threatened Species:Summary Statistics|}

Phylogeny A proposed phylogeny of the Plantae after Kenrick and CraneKenrick, Paul & Peter R. Crane. 1997. The Origin and Early Diversification of Land Plants: A Cladistic Study. (Washington, D.C.: Smithsonian Institution Press). ISBN 1-56098-730-8. is as follows, with modification to the Pteridophyta from Smith et al.Smith, Alan R., Kathleen M. Pryer, E. Schuettpelz, P. Korall, H. Schneider, & Paul G. Wolf. (2006). " A classification for extant ferns". Taxon 55(3): 705-731. The Prasinophyceae may be a paraphyletic basal group to all green plants.

{{clade (micromonads) |2={{clade |label1=Streptobionta |1={{clade |1={{clade |label1=[Embryophytes |1={{clade |1={{clade |label1=Stomatophytes |1={{clade |1={{clade |label1=Polysporangiates |1={{clade |1={{clade |label1=[Vascular plant |1={{clade |label1=Eutracheophytes |1={{clade |label1=Euphyllophytina |1={{clade |label1=Lignophytia |1={{clade |1='''[Spermatophyta''' (seed plants) |2=[Progymnospermophyta † --> |label2='''[Fern''' |2={{clade |1={{clade |1=[Pteridopsida (true ferns) |2=[Marattiopsida |3=[Equisetopsida (horsetails) |4=[Psilotopsida (whisk ferns & adders'-tongues) |5=[Cladoxylopsida † --> --> --> |label2=Lycophytina |2={{clade |1='''[Lycopodiophyta''' |2=[Zosterophyllophyta † --> --> |2=[Rhyniophyta † --> --> |2=''[Aglaophyton'' † |3=[Horneophytopsida † --> --> |2='''[Moss''' (mosses) |3='''[Anthocerotophyta''' (hornworts) --> --> |2='''[Marchantiophyta''' (liverworts) --> --> |2='''[Charophyta''' --> --> |3={{clade |label1='''[Chlorophyta''' |1={{clade |1={{clade |1=[Trebouxiophyceae (Pleurastrophyceae) |2=[Chlorophyceae --> |2=[Ulvophyceae --> --> --> -->

Embryophytes , a species of tree fern.Most familiar are the multicellular land plants, called embryophytes. They include the vascular plants, plants with full systems of leaf, Plant stem, and roots. They also include a few of their close relatives, often called bryophytes, of which mosses and Marchantiophyta are the most common.

All of these plants have eukaryote cells with cell walls composed of cellulose, and most obtain their energy through photosynthesis, using light and carbon dioxide to synthesize food. About three hundred plant species do not photosynthesize but are parasites on other species of photosynthetic plants. Plants are distinguished from green algae, which represent a mode of photosynthetic life similar to the kind modern plants are believed to have evolved from, by having specialized reproductive organs protected by non-reproductive tissues.

Bryophytes first appeared during the early Palaeozoic. They can only survive where moisture is available for significant periods, although some species are desiccation tolerant. Most species of bryophyte remain small throughout their life-cycle. This involves an alternation between two generations: a haploid stage, called the gametophyte, and a diploid stage, called the sporophyte. The sporophyte is short-lived and remains dependent on its parent gametophyte.

Vascular plants first appeared during the Silurian period, and by the Devonian had diversified and spread into many different land environments. They have a number of adaptations that allowed them to overcome the limitations of the bryophytes. These include a cuticle resistant to desiccation, and vascular tissues which transport water throughout the organism. In most the sporophyte acts as a separate individual, while the gametophyte remains small.

The first primitive seed plants, Pteridosperms (seed ferns) and Cordaites, both groups now extinct, appeared in the late Devonian and diversified through the Carboniferous, with further evolution through the Permian and Triassic periods. In these the gametophyte stage is completely reduced, and the sporophyte begins life inside an enclosure called a seed, which develops while on the parent plant, and with fertilisation by means of pollen grains. Whereas other vascular plants, such as ferns, reproduce by means of spores and so need moisture to develop, some seed plants can survive and reproduce in extremely arid conditions.

Early seed plants are referred to as gymnosperms (naked seeds), as the seed embryo is not enclosed in a protective structure at pollination, with the pollen landing directly on the embryo. Four surviving groups remain widespread now, particularly the conifers, which are dominant trees in several biomes. The angiosperms, comprising the flowering plants, were the last major group of plants to appear, emerging from within the gymnosperms during the Jurassic and diversifying rapidly during the Cretaceous. These differ in that the seed embryo (angiosperm) is enclosed, so the pollen has to grow a tube to penetrate the protective seed coat; they are the predominant group of flora in most biomes today.

Fossils .Plant fossils include roots, wood, leaves, seeds, fruit, pollen, spores, phytoliths, and amber (the fossilized resin produced by some plants). Fossil land plants are recorded in terrestrial, lacustrine, fluvial and nearshore marine sediments. Pollen, spores and algae (dinoflagellates and acritarchs) are used for dating sedimentary rock sequences. The remains of fossil plants are not as common as fossil animals, although plant fossils are locally abundant in many regions worldwide.

The earliest fossils clearly assignable to Kingdom Plantae are fossil green algae from the Cambrian. These fossils resemble calcified multicellular members of the Dasycladales. Earlier Precambrian fossils are known which resemble single-cell green algae, but definitive identity with that group of algae is uncertain.

The oldest known trace fossils of embryophytes date from the Ordovician, though such fossils are fragmentary. By the Silurian, fossils of whole plants are preserved, including the lycophyte Baragwanathia longifolia. From the Devonian, detailed fossils of rhyniophytes have been found. Early fossils of these ancient plants show the individual cells within the plant tissue. The Devonian period also saw the evolution of what many believe to be the first modern tree, Archaeopteris. This fern-like tree combined a woody trunk with the fronds of a fern, but produced no seeds.

The Coal Measures are a major source of Palaeozoic plant fossils, with many groups of plants in existence at this time. The spoil heaps of coal mines are the best places to collect; coal itself is the remains of fossilised plants, though structural detail of the plant fossils is rarely visible in coal. In the Fossil Forest at Victoria Park in Glasgow, Scotland, the stumps of Lepidodendron trees are found in their original growth positions.

The fossilized remains of conifer and angiosperm roots, stems and branches may be locally abundant in lake and inshore sedimentary rocks from the Mesozoic and Caenozoic eras. Coast Redwood and its allies, magnolia, oak, and Arecaceae are often found.

Petrified wood is common in some parts of the world, and is most frequently found in arid or desert areas where it is more readily exposed by erosion. Petrified wood is often heavily silicified (the organic material replaced by silicon dioxide), and the impregnated tissue is often preserved in fine detail. Such specimens may be cut and polished using lapidary equipment. Fossil forests of petrified wood have been found in all continents.

Fossils of seed ferns such as Glossopteris are widely distributed throughout several continents of the southern hemisphere, a fact that gave support to Alfred Wegener's early ideas regarding Continental drift theory.

Life processes Growth Most of the solid material in a plant is taken from the atmosphere. Through a process known as photosynthesis, plants use the energy in sunlight to convert carbon dioxide from the atmosphere into simple sugars. These sugars are then used as building blocks and form the main structural component of the plant. Plants rely on soil primarily for support and water (in quantitative terms), but also obtain nitrogen, phosphorus and other crucial elemental nutrients. For the majority of plants to grow successfully they also require oxygen in the atmosphere (for respiration in the dark) and oxygen around their roots. However, a few specialized vascular plants, such as Mangroves, can grow with their roots in anoxic conditions.

is the primary site of photosynthesis in plants.

Factors affecting growth The genotype of a plant affects its growth, for example selected varieties of wheat grow rapidly, maturing within 110 days, whereas others, in the same environmental conditions, grow more slowly and mature within 155 days.Robbins, W.W., Weier, T.E., et al, Botany:Plant Science, 3rd edition , Wiley International, New York, 1965.

Growth is also determined by environmental factors, such as temperature, available water, available light, and available nutrients in the soil. Any change in the availability of these external conditions will be reflected in the plants growth.

Biotic factors (living organisms) also affect plant growth.



Simple plants like algae may have short life spans as individuals, but their populations are commonly seasonal. Other plants may be organized according to their seasonal growth pattern:

Among the vascular plants, perennials include both evergreens that keep their leaves the entire year, and deciduous plants which lose their leaves for some part. In temperate and boreal climates, they generally lose their leaves during the winter; many tropical plants lose their leaves during the dry season.

The growth rate of plants is extremely variable. Some mosses grow less than 0.001 mm/h, while most trees grow 0.025-0.250 mm/h. Some climbing species, such as kudzu, which do not need to produce thick supportive tissue, may grow up to 12.5 mm/h.

Plants protect themselves from frost and dehydration stress with antifreeze proteins, Heat shock protein and sugars (sucrose is common). LEA (Late Embryogenesis Abundant) protein expression is induced by stresses and protects other proteins from aggregation as a result of desiccation and freezing.

Internal distribution elements in the shoot of a fig tree (Ficus alba): crushed in hydrochloric acid, between slides and cover slips.Nutrients and water from the soil and the organic compound produces in leaves are distributed to specific areas in the plant through the xylem and phloem. The xylem draws water and nutrients up from the roots to the upper sections of the plant's body, and the phloem conducts other materials, such as the glucose produced during photosynthesis, which gives the plant energy to keep growing and seeding.

The xylem consists of tracheids, which are dead hard-walled cells arranged to form tiny tubes to function in water transport. A tracheid cell wall usually contains the polymer lignin. The phloem however consists of living cells called sieve-tube members. Between the sieve-tube members are sieve plates, which have pores to allow molecules to pass through. Sieve-tube members lack such organs as nuclei or ribosomes, but cells next to them, the companion cells, function to keep the sieve-tube members alive.

Movement of nutrients, water, sugars and waste is effected by transpiration, conduction and absorption.

Transpiration The most abundant compound in most plants is water, serving a large role in the various processes taking place. Transpiration is the main process a plant can call upon to move compounds within its tissues. The basic minerals and nutrients a plant is composed of remain, generally, within the plant. Water, however, is constantly being lost from the plant through its metabolic and photosynthetic processes to the atmosphere.

Water is transpired from the plants leaves via stomata, carried there via leaf veins and vascular bundles within the plants cambium layer. The movement of water out of the leaf stomata creates, when the leaves are considered collectively, a transpiration pull. The pull is created through water surface tension within the plant cells. The draw of water upwards is assisted by the movement of water into the roots via osmosis. This process also assists the plant in absorbing nutrients from the soil as soluble salts, a process known as absorption.

Absorption Xylem cells move water and nutrient solutions upwards towards other plant organs from the roots and fine root hairs. Living roots cells actively absorb water in the absence of transpiration pull via osmosis creating root pressure. There are times when plants do not have transpiration pull, usually due to lack of light or other environmental elements. Water in the plant tissues may move to the roots to assist in passive absorption.

Conduction Xylem and phloem tissues are involved in the conduction processes within plants. The movement of foods throughout the plant takes place mainly in the phloem. Plant conduction (food movement) is from an area of high food content, place of manufacture (photosynthesis) or storage, to a place of food utilisation, or from a point of manufacture to storage tissues. Mineral salts are translocated in the xylem tissues.

Ecology The photosynthesis conducted by land plants and algae is the ultimate source of energy and organic material in nearly all ecosystems. Photosynthesis radically changed the composition of the early Earth's atmosphere, which as a result is now 21% oxygen. Animals and most other organisms are Aerobic organism, relying on oxygen; those that do not are confined to relatively rare anaerobic environments. Plants are the Autotroph in most terrestrial ecosystems and form the basis of the food web in those ecosystems. Many animals rely on plants for shelter as well as oxygen and food.

Land plants are key components of the water cycle and several other biogeochemical cycles. Some plants have coevolved with nitrogen fixation bacteria, making plants an important part of the nitrogen cycle. Plant roots play an essential role in soil development and prevention of soil erosion.

Distribution Plants are distributed worldwide in varying numbers. While they inhabit a multitude of biomes and ecoregions, few can be found beyond the tundras at the northernmost regions of continental shelf. At the southern extremes, plants have adapted tenaciously to the prevailing conditions. (See Antarctic flora.)

Plants are often the dominant physical and structural component of habitats where they occur. Many of the Earth's biomes are named for the type of vegetation because plants are the dominant organisms in those biomes, such as grasslands and forests.

Ecological relationships , a species of carnivorous plant.Numerous animals have coevolved with plants. Many animals pollinate flowers in exchange for food in the form of pollen or nectar. Many animals biological dispersal, often by eating fruit and passing the seeds in their feces. Myrmecophytes are plants that have coevolved with ants. The plant provides a home, and sometimes food, for the ants. In exchange, the ants defend the plant from herbivores and sometimes competing plants. Ant wastes provide organic fertilizer.

The majority of plant species have various kinds of fungi associated with their root systems in a kind of mutualistic symbiosis known as mycorrhiza. The fungi help the plants gain water and mineral nutrients from the soil, while the plant gives the fungi carbohydrates manufactured in photosynthesis. Some plants serve as homes for endophyte fungi that protect the plant from herbivores by producing toxins. The fungal endophyte, Neotyphodium coenophialum, in tall fescue (Festuca arundinacea) does tremendous economic damage to the cattle industry in the U.S.

Various forms of parasitism are also fairly common among plants, from the semi-parasitic mistletoe that merely takes some nutrients from its host, but still has photosynthetic leaves, to the fully parasitic broomrape and toothwort that acquire all their nutrients through connections to the roots of other plants, so have no chlorophyll. Some plants, known as myco-heterotrophs, parasitize mycorrhizal fungi, and hence act as epiparasites on other plants.

Many plants are epiphytes, meaning they grow on other plants, usually trees, without parasitizing them. Epiphytes may indirectly harm their host plant by intercepting mineral nutrients and light that the host would otherwise receive. The weight of large numbers of epiphytes may break tree limbs. Many orchids, bromeliads, ferns and mosses often grow as epiphytes. Bromeliad epiphytes accumulate water in leaf axils to form phytotelmata, complex aquatic food webs.Bromeliad Phytotelmata

A few plants are carnivorous plant, such as the Venus Flytrap and sundew. They trap small animals and digest them to obtain mineral nutrients, especially nitrogen.

Importance plant. Potatoes spread to the rest of the world after European contact with the Americas in the late 1400s and early 1500s and have since become an important field crop. in storage for later processing at a sawmill. branch showing 27 annual growth rings, pale sapwood and dark heartwood, and pith (centre dark spot). The dark radial lines are small knots.The study of plant uses by people is termed economic botany or ethnobotany. They are often used as synonyms but some consider economic botany to focus mainly on uses of modern cultivated plants, while ethnobotany studies uses of indigenous plants by native peoples. Human cultivation of plants is part of agriculture, which is the basis of human civilization. Plant agriculture is subdivided into agronomy, horticulture and forestry.

Food Virtually all human nutrition depends on land plants directly or indirectly. Much of human nutrition depends on cereals, especially maize, wheat and rice or other staple crops such as potato, cassava, and legumes. Other parts from plants that are eaten include fruits, vegetables, nut (fruit), herbs, spices and flowers. Beverages from plants include coffee, tea, wine, beer and alcohol. Sugar is obtained mainly from sugar cane and sugar beet. Cooking oils and margarine come from corn, soybean, canola, safflower, sunflower, olive and others. Food additives include gum arabic, guar gum, locust bean gum, starch and pectin.

Nonfood products Wood is used for buildings, furniture, paper, cardboard, musical instruments and sports equipment. Cloth is often made from cotton, flax or synthetic fibers derived from cellulose, such as rayon and acetate. Renewable fuels from plants include firewood, peat and many other biofuels. Coal and petroleum are fossil fuels derived from plants. Medicines derived from plants include aspirin, taxol, morphine, quinine, reserpine, colchicine, digitalis and vincristine. There are hundreds of herbal supplements such as ginkgo, Echinacea, feverfew, and Saint John's wort. Pesticides derived from plants include nicotine, rotenone, strychnine and pyrethrins. Drugs obtained from plants include opium, cocaine and cannabis (drug). Poisons from plants include ricin, Conium and curare. Plants are the source of many natural products such as fibers, essential oils, dyes, pigments, waxes, tannins, latex, gums, resins, alkaloids, amber and cork. Products derived from plants include soaps, paints, shampoos, perfumes, cosmetics, turpentine, rubber, varnish, lubricants, linoleum, plastics, inks, chewing gum and hemp rope. Plants are also a primary source of basic chemicals for the industrial synthesis of a vast array of organic chemicals. These chemicals are used in a vast variety of studies and experiments.

Aesthetic uses Thousands of plant species are cultivated to beautify the human environment as well as to provide shade, modify temperatures, reduce windspeed, abate noise, provide privacy and prevent soil erosion. People use cut flowers, dried flowers and house plants indoors. Outdoors, they use lawngrasses, shade trees, ornamental trees, shrubs, vines, herbaceous perennials and bedding plants. Images of plants are often used in art, architecture, humor, Language of flowers and photography and on textiles, money, stamps, flags and coats of arms. Living plant art forms include topiary, bonsai, ikebana and espalier. Ornamental plants have sometimes changed the course of history, as in tulipomania. Plants are the basis of a multi-billion dollar per year tourism industry which includes travel to arboretums, botanical gardens, garden tourism, national parks, tulip festivals, rainforests, forests with colorful autumn leaves and the National Cherry Blossom Festival. Venus flytrap, sensitive plant and resurrection plant are examples of plants sold as novelties.

Scientific and cultural uses Tree rings are an important method of dating in archeology and serve as a record of past climates. Basic biological research has often been done with plants, such as the pea plants used to derive Gregor Mendel's laws of genetics. Space stations or space colonies may one day rely on plants for Controlled Ecological Life Support System. Plants are used as National emblem and state emblems, including List of U.S. state trees and state flowers. Ancient trees are revered and many are List of famous trees. Numerous world records are held by plants. Plants are often used as memorials, gifts and to mark special occasions such as births, deaths, weddings and holidays. Plants figure prominently in Trees in mythology, religion and List of fictional plants. The field of ethnobotany studies plant use by indigenous cultures which helps to conserve endangered species as well as discover new herbalism. Gardening is the most popular leisure activity in the U.S. Working with plants or horticulture therapy is beneficial for rehabilitating people with disabilities. Certain plants contain psychotropic chemicals which are extracted and ingested, including tobacco, Cannabis (drug) (marijuana), and opium.

Negative effects Weeds are plants that grow where people do not want them. People have spread plants beyond their native ranges and some of these introduced plants become invasive species, damaging existing ecosystems by displacing native species. Invasive plants cause billions of dollars in crop losses annually by displacing crop plants, they increase the cost of production and the use of chemical means to control them effects the environment.

Plants may cause harm to people. Plants that produce windblown pollen invoke allergic reactions in people who suffer from hay fever. A wide variety of plants are List of poisonous plants. Several plants cause skin irritations when touched, such as poison ivy. Certain plants contain psychotropic secondary metabolite, which are extracted and ingested or smoked, including tobacco, cannabis (marijuana), cocaine and opium, causing damage to health or even death. Both illegal and legal drugs derived from plants have negative effects on the economy, effecting worker productivity and law enforcement costs. Some plants cause allergic reactions in people and animals when ingested, while other plants cause food intolerances that negatively effect health.

See also

References Further reading General:

Species estimates and counts:

External links

Botanical and vegetation databases



BBC - Gardening - Plants
Find out more about plants. ... What to grow? Look up information about thousands of plants using our searchable database.

BBC - Schools Science Clips - Growing plants
An interactive simulation of the growth of a seedling into a flowering plant to help children aged 5-6 investigate the conditions plants need for growth.

Home: Plants Limited - Wholesale Nurseries Landscape Industry Trade ...
Suppliers to the landscape industry, in Chobham, Surrey.

Buy Plants Online from our massive Garden Plant range
Choose a garden plant to buy from our massive selection of plants and gardening products at very competitive prices from Jacksonb s Online Garden Centre.

Plant Explorer
Plant explorer - A website resource for primary children exploring plants!

UK gardening website specialising in garden plants and garden pots and ...
UK gardening website. Garden Centre Online UK offering a massive selection of quality plants, topiary, bay trees, bamboo, ornamental grasses at unbeatable prices delivered direct ...

The Royal Horticultural Society - Plants
Plants are the backbone of any garden. The RHS has a wealth of information on plants for all situations and how to grow them to perfection.

A-Plant - Home
Non-operated equipment outsourcing and rental. Includes a section on trenchless technology equipment available for rent.

UK Plants on Sale: Special Offers from Crocus.co.uk
Garden plant special offers from Crocus.co.uk ... Rose offers. The nursery is full of colour and promise, particularly in the rose beds where 86 of the classiest varieties are ...

House Plants - Send exotic house plants for UK delivery from Bunches.
Bunches House Plants - Send exotic house plants, flowering plants and indoor plants for UK delivery. Make someone's day with our flowering house plants. They bring life & colour ...

 

Plant



 
Copyright © 2008 Hintcenter.com - All rights reserved.
Home | Terms of Use | Privacy Policy
All Trademarks belong to their repective owners. Many aspects of this page are used under
commercial commons license from Yahoo!