how do plants communicate?
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Plant communication is all based on chemicals.\n\nThe idea that plants communicate chemically with one another has been around for a couple of decades, but it's only been in the last few years that solid scientific evidence has been accumulated to support the notion.\n\nOver three seasons spanning 1996 through 1998, researchers from the University of California in Davis monitored wild tobacco plants growing near sagebrush. They clipped the leaves of some of the sagebrush plants to mimic the damage caused by insects. The sagebrush plants responded with a puff of a chemical called methyl jasmonate. In response, tobacco plants downwind immediately begin boosting the level of an enzyme called PPO that makes their leaves less tasty to plant-eating insects. Within minutes of the clipping of the sagebrush, the plants' PPO levels quadrupled.\n\nIt worked, too. Tobacco plants next to the clipped sagebrush suffered sixty percent less damage from grasshoppers and caterpillars than tobacco plants next to unclipped sagebrush.\n\nThen, last fall, scientists at Kyoto University in Japan let spider mites loose on lima-bean plants and tracked the plants' responses. They found five different defense mechanisms. First, each injured plant released a chemical that changed its flavor, making it less attractive to the mites (although I personally nd it hard to imagine anything less attractive than the taste of a lima bean to begin with).\n\nThen the plants released other chemicals that drifted away. Other lima bean plants received the chemical and immediately begin giving off the same chemicals, making themselves less tasty and warning still more lima bean plants, before the mites even reached them.\n\nMost amazingly, some of the released chemicals had the effect of summoning a whole new batch of mites--mites that, rather than eating lima bean plants, preferred to eat the spider mites attacking the lima bean plants.\n\nThe Japanese researchers even found that the plants could distinguish between insect damage and crushing damage. They crushed some leaves and stems and found that although the injured plants released chemicals, the surrounding plants ignored them, somehow recognizing no real danger existed. (It appears that substances in the attacking insects' saliva are required to trigger the anti-insect chemical response in the plant.)\n\nOther examples from agriculture are also known. Corn under attack from armyworms, for instance, puts out a chemical signal that attracts a predatory wasp. The wasp lays its eggs inside the armyworm; when they hatch, the wasp larva eat the armyworm.\n\nAnd a study released last week shows that this kind of signaling exists not only in agricultural situations and in labs, but in the wild--which means it is likely widespread throughout the plant kingdom.\n\nResearchers from the Max Planck Institute for Chemical Ecology in Jena, Germany, discovered that when a species of wild tobacco plant that grows in the southwestern United States is damaged by hornworms (the larva of the hawkmoth) it releases chemicals that attract predatory insects that kill the larva.\n\nSuch chemical calls for helps benefit both the plant being attacked and the predators, who would otherwise find it very difficult to find the larva, which are camouflaged and also tend to feed on the underside of leaves, where they can't be seen. Most likely the plant developed a chemical defense that predators evolved to take advantage of, but the result is the same as if the plant consciously sent out a cry for help.\n\nAgricultural scientists are already looking for ways to use this new understanding of plant communication to improve the way farmers fight pests. For example, these kind of indirect defenses could be genetically engineered into crops so that they could more effectively summon natural predators. That could reduce the need for chemical pesticides--in fact, you'd want to avoid chemicals, because they would kill the predator
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Pardon me if I am incorrect but i dont think that plants NEED more energy rather they HAVE more energy. Each time you move up the food chain, only 10% (?) of the original energy the organism had is retained. The rest is lost. Since plants are at the bottom of the food chaing and are autotrophs, they receive 100% of the energy they converted through photosynthesis. Then the rabbit who eats the plant gets only 10% of that and the fox who eats the rabbit gets only 1%.
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>Plant do not contain much organelles inside the cell\n so they posses large vacuoles in their cytoplasm.\n>Where as animals as more cell organelles in their cell\n They store some bio-molecules which is required for them during the necessary period like starvation.\nso animals do not have vacuole.\n\n>Plants are auto-tropic which can synthesis their own food.\nplant get their food by photosynthesis which is the       biochemical process. \nThe chloroplast plays the major role in photosynthesis.\n>Animal is an hetero-tropic depend on other for food.\nso they don't need chloroplast.\n\nchloroplast contains chlorophyll pigment which is green coloured pigment also make the plants to appear green.\nso animal do not require chloroplast anyway.
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Oxygen is one. Plants pick up CO2 and convert it to oxygen.\nWater\nFish\nTrees
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On the lower surface of leaves are tiny pores called STOMATA.\nAround the edge of these pores are guard cells.\nThe guard cells can change shape to open or close the pores.\nThis allows or prevents water loss.\n\nLook up STOMATA.\nYou could also try this excellent website:
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Excellent question.  \n\nThis is due to a process called osmosis.  Osmosis is the net movement of water molecules in and out of a partially permeable membrane (a kind of barrier that only allows certain molecules to pass through), from a region of their higher concentration to a region of their lower concentration.\n\nIts pretty self-explanatory here.  Since the concentration of water is higher inside than outside of the plant, water moves out of the plant, resulting in the plant dehydrating and dying.
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Verbal communication.
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I'm not sure what your asking???  \nIs it the plant cell????
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http://www.biologyreference.com/Ve-Z/Water-Movement-in-Plants.html\n\nThe Cohesion-Tension Theory\nThe major mechanism for long-distance water transport is described by the cohesion-tension theory, whereby the driving force of transport is transpiration, that is, the evaporation of water from the leaf surfaces. Water molecules cohere (stick together), and are pulled up the plant by the tension, or pulling force, exerted by evaporation at the leaf surface.\n\nWater will always move toward a site with lower water potential, which is a measure of the chemical free energy of water. By definition, pure water has a water potential of 0 MegaPascals (MPa). In contrast, at 20 percent relative humidity, the water potential of the atmosphere is -500 MPa. This difference signifies that water will tend to evaporate into the atmosphere. The water within plants also has a negative potential, indicating water will tend to evaporate into the air from the leaf. The leaves of crop plants often function at -1 MPa, and some desert plants can tolerate leaf water potentials as low as -10 MPa. The water in plants can exist at such low water potentials due to the cohesive forces of water molecules. The chemical structure of water molecules is such that they cohere very strongly. By the cohesion-tension theory, when sunlight strikes a leaf, the resultant evaporation first causes a drop in leaf water potential. This causes water to move from stem to leaf, lowering the water potential in the stem, which in turn causes water to move from root to stem, and soil to root. This serves to pull water up through the xylem tissue of the plant.\nFrom Root to Leaf\nPlants have root hairs and often mycorrhizal fungi at the root surface, both of which serve to filter the soil water as it enters the plant. Mycorrhizae are symbiotic associations between plant roots and fungi. The root cells and mycorrhizal fungi both actively uptake certain mineral nutrients. Mycorrhizae can be particularly important for the uptake of phosphate. The active uptake of minerals by living cells of the root and the subsequent transfer of minerals to the xylem can result in positive root pressures, with water potentials above 0 MPa. This occurs only under certain conditions, such as at night or during rainstorms, when water loss from the leaves is minimal. Such positive root pressures disappear with the onset of leaf transpiration.\n\nWater molecules move from the soil into living cells of the root, and eventually into the transport cells of the xylem, known as tracheids and vessels. These xylem cells are dead and hollow, allowing rapid water transport. They also have hardened cell walls to help them resist the tendency to collapse as water is sucked through them. Both tracheids and vessels \n\n \nA drop of guttation, water extruded by a plant's root pressure, on a blade of grass. have pits on the sides of their walls, which include porous areas for side-to-side transport. Unlike tracheids, a vessel is composed of many cells stacked end to end, with perforations between cells, allowing for more efficient transport.\n\nThe long-distance transport of the water molecule occurs first within the xylem cells of the root, then the xylem of the stem and branch, and then into the xylem of a leaf midrib and vein. Driven by transpiration, the water molecule is pulled from the nonliving tracheids and vessels of the xylem in the living cells of the leaf mesophyll (middle layer) and to the surface of mesophyll cell walls. The water molecule then evaporates into a leaf inter-cellular air space and finally out of a stomatal pore and into the atmosphere. Though photosynthetic action consumes some water, only a small fraction of the water that travels through the plant is used directly for the photo-synthetic reaction, which occurs in leaf mesophyll cells. Instead, most water is lost by transpiration through the stomates.\nThe Role of Stomates\nLeaves of land plants are covered with a waxy cuticle that pr
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Neuro-motor system, no way.  That would involve neurons and neurotransmitters.  None of these have been found in plants.\n\nHowever, there is definite physiologic responses that could be defined as behaviour in plants.  These responses and stimuli are much simpler than we can appreciate.
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I wouldn't think that they are aware as we understand our awareness of existance.\n\nHowever, plants do know when something is harming them.  It has been proven that they produce a chemical that is realeased through the air when something damages them.  It is thought that this is a way of letting other plants in the area of possible, impending danger.\n\nIs this usefull?  Maybe not to us, but it works for plants.
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The plant kingdom, one of four eukaryotic kingdoms, is composed of multicellular, autotrophic organisms that photosynthesize to fix inorganic carbon (from atmospheric CO2) into organic molecules. Plants are the foundation of all terrestrial habitats, and serve as terrestrial Earth’s primary autotrophs, making organic molecules that will cycle through the food webs of most ecosystems. The photosynthetic capabilities of plants ultimately allow all terrestrial members of the animal kingdom to survive.\n\nOne hallmark of plant cells is the cell wall, which, in contrast to cell walls of single-celled organisms, is made of cellulose. The cell walls provide support for plant cells, as well as support and cohesiveness for plant tissue. Unlike the plasma membrane, the cell wall is not a semipermeable membrane, and so the shared cell walls between adjoining plant cells must have openings, plasmodesmata, to allow material transport and communication. Another distinguishing feature of plant cells is the large central vacuole, which stores a water reserve as well as essential chemicals, waste products of cellular metabolism, and sometimes other species-specific functions, such as storage of poisons or flower pigments. The central vacuole can also aid in cell growth by absorbing water.\n\nExcluding a few photosynthetic protists and cyanobacteria, plant cells are the only cells that contain chloroplasts. These organelles carry out the processes of photosynthesis, converting light energy into chemical energy and storing it as sugar. As well as producing food for ecosystems, photosynthesis releases oxygen molecules as byproducts, which replenish atmospheric oxygen used in cellular respiration and form a layer of ozone, O3, which shields the earth from solar ultraviolet rays.\n\nPlants probably evolved from multicellular green algae called charophytes and were the first multicellular organisms to colonize land. In order to do this, plants had to evolve several new characteristics in the form of distinct, specialized organs, which protists and algae lack. First of all, plants need to have a form of anchorage in the ground and rigid stem tissue for support. Thus, plants have developed root structures, which, in addition to anchoring a plant in the ground, allow the plant to take up chemical nutrients from the soil. Cellulose-containing cell walls developed in plant cells to maintain a form of rigidity in the part of the plant above ground. These account for the stiffness of plant stems and from the hardness of wood. Marine algae, which are suspended in water and can absorb nutrients from all around, have neither of these structures. Also, to prevent water loss in a terrestrial environment, plants evolved a waxy cuticle, which covers stem and leaf surfaces. Gases for photosynthesis can not diffuse across this cuticle, so tiny pores called stomata are present in the cuticle.\n\nBecause plants have organs that serve different functions, they must have systems to distribute necessary substances throughout the plant. Sugars, produced in photosynthesis, must be distributed to the body and roots of the plant that do not photosynthesize. Water and nutrients from the soil, taken up by the roots, must also make their way into the plant body and leaves. To perform these essential functions, plants contain a vascular tissue network, which consists small tubes running throughout the plant. There are two types of vascular tissue: xylem, which are small tubes dead cells that transport water and minerals up from the roots, and phloem, which are living cells that distribute sugars produced in photosynthesis.\n\nAlso characteristic of plants, as well as some algae, are gametangia that protect gametes. These are pockets of cells that protect the egg cell, and where the egg is fertilized.\n\nPlants have a life cycle unlike that of any animal, fungus, or bacteria. Probably a trait inherited from protistan (algal) ancestors, diploid and haploid generations alternate
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1. Plant cell are constantly differentiating in a plant, as long as it has embryonic tissure (i.e. buds). In these buds, embryonic cells are born, grow and differentitate into all sorts of plant cell types.\n2. Plants facilitate the process by bringing to these burgeoning cells all the nutrients they need in their infancy. This differentiation process is crucial because it creates all the different types of cell a plant needs to live, i.e. conducting cells, structure cells, photosynthetic cellls, root cells, etc.
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Animals are supported by a skeleton, made of bone.  Plants don't have skeletons, they use a cell wall to give them support.  Such walls wound make movement impractical.
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Animals have a circulatory system that transports fluids, chemicals, and nutrients around within the animal body. Some plants have an analogous system: the vascular system in vascular plants; trumpet hyphae in bryophytes.\n\nRoot hairs are thin-walled extensions of the epidermal cells in roots. They provide increased surface area and thus more efficient absorption of water and minerals. Water and dissolved mineral nutrients enter the plant via two routes. \n\n\nWater and selected solutes pass through only the cell membrane of the epidermis of the root hair and then through plasmodesmata on every cell until they reach the xylem: intracellular route (apoplastic). Water and solutes enter the cell wall of the root hair and pass between the wall and plasma membrane until the encounter the endodermis, a layer of cells that they must pass through to enter the xylem: extracellular route (symplastic). \n\n\nThe endodermis has a strip of water-proof material (containing suberin) known as the Casparian strip that forces water through the endodermal cell and in such a way regulates the amount of water getting to the xylem. Only when water concentrations inside the endodermal cell fall below that of the cortex parenchyma cells does water flow into the endodermis and on into the xylem.\nXylem and Transport \nXylem is the water transporting tissue in plants that is dead when it reaches functional maturity. Tracheids are long, tapered cells of xylem that have end plates on the cells that contain a great many crossbars. Tracheid walls are festooned with pits. Vessels, an improved form of tracheid, have no (or very few) obstructions (crossbars) on the top or bottom of the cell. The functional diameter of vessels is greater than that of tracheids.\n\nWater is pulled up the xylem by the force of transpiration, water loss from leaves. Mature corn plants can each transpire four gallons of water per week. Transpiration rates in arid-region plants can be even higher. Water molecules are hydrogen bonded to each other. Water lost from the leaves causes diffusion of additional water molecules out of the leaf vein xylem, creating a tug on water molecules along the water columns within the xylem. This "tug" causes water molecules to rise up from the roots to eventually the leaves. The loss of water from the root xylem allows additional water to pass throught the endodermis into the root xylem.\n\nCohesion is the ability of molecules of the same kind to stick together. Water molecules are polar, having slight positive and negative sides, which causes their cohesion. Inside the xylem, water molecules are in a long chain extending from the roots to the leaves. \n\nAdhesion is the tendency of molecules of different kinds to stick together. Water sticks to the cellulose molecules in the walls of the xylem, counteracting the force of gravity and aiding the rise of water within the xylem. \n\nCohesion-Adhesion Theory\nTranspiration exerts a pull on the water column within the xylem. The lost water molecules are replaced by water from the xylem of the leaf veins, causing a tug on water in the xylem. Adhesion of water to the cell walls of the xylem facilitates movement of water upward within the xylem. This combination of cohesive and adhesive forces is referred to as the Cohesion-Adhesion Theory.\n\n\nGuard Cells Regulate Transpiration\nIn most environments, the water concentration outside the leaf is less than that inside the leaf, causing a loss of water through openings in the leaf known as stomata (singular = stoma). Guard cells are crescent-shaped cells of the epidermis that flank the stoma and regulate the size of the opening. Together, the guard cells and stoma comprise the stomatal apparatus. The inner wall of the guard cell is thicker than the rest of the wall. When a guard cell takes up potassium ions, water moves into the cell, causing the cell to become turgid and swell, opening the stoma. When the potassium leaves the guard cell, the water
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Plants need a number of things to grow. They need water from the soil, energy from the sun, carbon dioxide from the air and they need nutrients.  Very often one or more of these resources are limiting so that the plant can not grow as big as it would otherwise. Often the most limiting resources are water or nutrients. This can be helped by irrigation in the case of water or by fertilisers in cases were nutrients are deficit. Nutrients are building blocks in the plant. For example nitrogen, which is most abundant in the plant except for carbon, is an important element in \nproteins, as is sulphur. Magnesium is needed in the chlorophyll so that the plants can gain energy from sunlight. These elements can be given to the \nplants by fertilising the soil. Nitrogen, phosphorous and potassium are generally given in the largest amounts. Sulphur, magnesium, copper, zinc and so on are given much sparse and are called micronutrients. Carbon is \nnot a nutrient in the same way, as the roots do not take it up. It is assimilated in needed quantities from the air as carbon dioxide.
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Water and "nutrients" depending on the specific type of cell. Plant cells need inorganic nitrogen compounds (ammonia, nitrate), phosphate, iron, magnesium, manganese, copper,...\nAnimal cells need organic substances like sugars or amino acids (which plant cells can produce on their own) additionally to vitamins and ions (iron, copper, cobalt, zinc, molybdenum, iodine, selenium,...)