What process is involved ensuring continuos supply of water through xylem in the plant body?
355608
Transpiration pull, root pressure, etc. Root pressure occurs because water cannot pass back out of a root once it has been absorbed because of the Casparian strip. Therefore, the water has nowhere to go but up the xylem, so water is always there (unless there is a very long, severe drought and the plant dies). Transpiration is the evaporation of H2O through the leaves. When  cells in the leaves are low on water, they pull it in from other cells by osmosis. Then those cells pull in water, and the process continues. When it gets to the vein in a leaf, all the water is pulled out, so it draws water from the xylem, and causes more water to be pulled up. This is called transpiration pull and contributes to keeping water in the xylem.
722375
phloem are the vascular tissues that transport sucrose. xylem transports water. naturally, a parasite would go for the food source rather than just the water.
1030327
The plant leaf is covered with  a waterproof waxy layer called the cuticle.  The lower leaf surface contains small holes called stomata.  These stomata allow gases to enter and leave the leaf. The only way water can enter a plant is through it roots.  Water vapor leaves the leaf pulling on the water in the xylem that has been absorbed by the roots.  Water thus goes in one direction from the roots, to the xylem, to the leaf, and then out into the atmosphere.  If you have ever been in a tropical setting it always seem very humid.  This is caused by all the water leaving the plants through their leaves.
293716
xylem and phloem cells
29324
Plants have small openings on the underside of their leaves called stomata. The roots pull in water and it travels up and out the stomata. The lower humidity outside the plant pulls the water out.
1030723
stomata are minute openings on the epidermis of leaves which is surrounded by guard cells.the strucutre of a guard cell :\nguard cells generally have thick and non elastic walls towards the pore and thin and elastic walls on the opposite side.\nthe mechanism of stomatal transpiration depends upon the opening and closing of stomata.stomata opens during day time and close at night.the the opening and closing of stomata dependson to how much water is present in the gaurd cells.when there is more water,the guard cells become turgid and the stomata opens and when the amount of water decreases the guard become flaccid and stomata close. \n\nthere are two theories pertaining to this , steward's starch hydrolysis theory and K + pump theory.\nu can surf the net to find out more on this if u want to .
505659
That is xylem.\nPhloem transports manufactured materials, e.g. sugars.\nLook here:
380794
Basically by osmosis. The cell absorbs nutrients and oxygen through the cell wall from the blood circulating in the capillaries. The oxygen is absorbed by the body in an exchange in the lungs and nutrients are absorbed through the small and large intestine and they all travel in the blood stream to the cells.
501189
Gymnosperms are generally wind-pollinated, which puts pressure on them to be taller. Angiosperms have more options available, so the selection pressure would be less. Water is always conducted by capillary pressure, but in the tallest trees water from the roots is augmented by water vapor collected from the air through stomata in the needles/leaves.
1126238
Primary Growth: Apical meristem is responsible for primary root and stem growth in vascular plants.\n \nPrimary Root Growth: is concentrated near the tip and results in the root growing in length. The root tip contains 4 zones of development: The root cap, which protects the area behind it and softens the soil ahead of it by producing a polysaccharide. The apical meristem, is an area of rapidly dividing cells. It will replace the cells of the root cap as they wear away and push cells above them that will develop into the main tissues of the plant. The zone of elongation, is an area where the cells elongate 10 times their original length. This elongation helps push the root into the soil. The zone of maturation, is the area farthest from the root tip. Here the new cells will specialize and carry out the functions of the epidermal, ground, and vascular tissue. The primary tissues in a dicot root are arranges in a central x pattern for the xylem with the phloem located in each of the angles of the xylem. In a monocot the vascular tissues are alternated in a circle.\nPrimary Stem Growth: begins at the tip of the terminal bud in the area called the apical meristem. The cell divisions are responsible for the stem's growth in length. The primary vascular tissue in monocots takes on a scattered arrangement. In a dicot, it takes a circular pattern.\n \nSecondary Growth: Increases the girth of a stem it is caused by the vascular and cork cambium.\n \nVascular Cambium: meristematic parenchyma produces xylem on the inside and phloem on its outer side. The secondary xylem accumulates and forms the wood. The secondary phloem does not accumulate and is sloughed off with the bark.\nCork Cambium: forms in the outer cortex. Produces cork and epidermal tissues.\nWood has 2 zones: Heartwood- the older (inner) layers of xylem blocked with resins. It is non -functional in water transport. Sap wood- outer xylem, vascular cambium, phloem and cork cambium. Conducts water and food.
31595
Diffusion is transfer of ions or any semipermeable substance through semipermeabe membrane,with help of concentration Gradient across the membrane. Osmosis is loss of water and vapours frm tissue or organised structure like stomata
1061953
the root system is the part of the plant responsible for absorption of minerals and water in addition to the fixation of the plant. first of all absorption of minerals takes place through an active process called active transport since minerals are present in low concentration in the soilcompared with the concentration of minerals present in the root hair cells therefore the root hair cells have to consume energy in order to take these minerals against their concentration gradient this is why the root hair cells contain a large number of mitochondria which is the power house of the cell that releases energy by a process called respiration second of all the absorption of water occurs through process called osmosis since water is present in high concentration in the soil compared with the concentration of water in the root hair cells as a result water will move from the soil into the root hair cells through a partialy permeable membrane called the cell membrane after allthe absorption happens water and the dissolved minerals willmove along the xylem vessel by three processes cappilary action, root pressure and transpiration (evaporation of water from the leaf creating a suction force which pulls the water coloumn up through the xylem vessel.in the leaf structure the midrib branches into many veins to ensure that all photosynthesising and normal cells are close to the water supply then the main process of transport between the cells is diffusion the movement of molecule from regions of high concentration to regions of low concentration down the concentration gradient.
15201
The leaves on any tree/plant work mainly as the energy center to enhance the food supply of the plant.  Photosynthesis is the primary action within the leaves, not the storage of water.  The roots, and the trunk of the tree maintain the water.\n\nSo when a tree looses it's leaves it simply maintains it's primary surface, ie trunk and branches, by storing the water within the lower roots, and within the innermost section of the trunk.
337412
The answer you are looking for is in the soil-plant-atmosphere continuum.  I'm too tired to give a full answer now so I will come back to this.\n\nIt basically works on negative pressure.  Air is the driest in the continuum and pulls water through the stomates from the xylem (not the phloem) up the stem from the roots, from the soil.\n\nI'll come back later.
149916
Only vascular plants have transport tissues; some cells are differentiated into phloem and xylem.
61042
Yes. It does. Since there is more sugar in the water outside of the plant than there is in the water in the plant, the sugar solution will be hypertonic (higher concentration of solutes). This will cause osmosis to occur, causing water to flow out of the plant and into the sugar water to equilize the content. This will drain the vacuoles in the plant cells, and cause them to shrivel up inside of the cell wall.
600353
Others have answered the question with drinking salt water.  The stomatas are pores in leaves that regulate the absorption & evaporation of water, along with gas exchange.\n\nDepending on the evnironmental condition, stomata will open up if there's lots of moisture in envoronment to absrob extra water.  If environment is dry, stomata will close to conserve its water content by reduing the evaporation.\n\nEffects of salt water on stomata, I'm not very sure but it's sure to give a lot of stress on the plant.  Stomata will open up a lot more in wet condition, and close longer & tightly during dry condition.\n\nSo main thing is, that if you give plants salt water, it's like giving very little water.