what are the mechanisms of transpiration in plants?
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.
779075
Close because the plant takes in CO2 and so it will prevent any CO2 from leaving the cell because it need them to carry out photosynthesis. Once they have enough, the stomata are closed so that they don't escape.
496338
this is bcos of the  turgor pressure built in the plant trigger the guard cells to contracts&expand causing excess  water to get out.
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.
411060
There are the reason for that-\n1-High transpiration rate renders tree leaves cool.\n2-High moisture niche near trees,evaporation renders cooling effect.\n3-Wind passing through leaves becomes less warmer.\n4-Green plants not only absorb a significant portion of the sunlight to invest as energy in photosynthesis to produce sugar resulting into fall in temperature.
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 .
146756
I think when plant absorb water, or H2O, they use the H, or the hydrogen, and aspirate (or "exhale" in animal terms) the oxygen they take in as a liquid as a gas. The aspiration I believe is very slow and could take 100 plants 100 years, longer than the average lifespan of a human being, to see significant increases in oxygen levels.
854751
Abscisic acid causes the stomates to close during times of water stress thus reducing the plant's water loss. It also increases the hydraulic conductivity of the roots.
289845
Yes, they have stoma which open and close pores on leaves.  Stoma are sensitive to moisture levels.  The leave turning thing is probably a different mechanism.  But yeah plants are very sensitive to water levels, esp in desert areas.  The leaves need water for photosynthesis so it makes sense that they have specialized to capture the most water.
54609
Keep the cell contents bound together,exchange gases and excreta,Semi permeable entry i.e. it protects the cell by allowing only some Substances to enter the cell, maintains the shape of the cell and helps in transfer of water from cell wall as it has hydrophilic proteins in plants
228888
There are various examples of such adaptations - the most glaring one being the cactus where the leaves have been modified into thorns to reduce surface area and hence transpiration.
128854
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:
867974
Oxygen transfers via osmosis through cell walls  from regions of high concentration (ie, the haemoglobin) to the tissue cells where there is a lower concentration. At the same time the tissue cells release carbon dioxide which lowers the partial pressure creating a diffusion gradient for the the oxygen to move along.
133937
This is more of a biological question, but as water enters soil, a plant's roots will essentially "drink" the water and provide the plant with it. The process of how the plant takes in the water is unknown at least to me.
17761
Flowers drink water with a capillary action.  Capillary action happens when water molecules are more attracted to the surface they travel along than to each other. In paper towels, the molecules move along tiny fibers. In plants, they move through narrow tubes that are actually called capillaries. Plants couldn't survive without capillaries because they use the water to make their food.  There is an experiement you can try at the link below.
515638
Transpiration, the properties of water, and the vascular tissues help the trees to suck water from the very bottom of the roots to the top of the tree leaves. Transpiration is caused when water is sucked from the root tips of the tree and into the vascular tissue called xylem. Because two of the properties of water state that water is adhesive (they stick to stuff) and cohesive (they stick together), these water molecules stick to the xylem as well as each other, using it's bonds to pull each other up the tree. And when the stomata (the hole on the underside of the leaf) opens for gas exchange, one water molecule at a time evaporates from the leaf, thus pulling the chain up one by one. Hope that helps!
146103
Surface tension refers to hydrogen bonds between water molecules.  Basically, these molecules are held together very tightly by the h-bonds.\n\nWhen one water molecule evaporates from a leaf, it pulls the column of water up via the h-bonds.  The water potential outside the plant is much, much less than that inside the plant, so the water is trying to leave the plant.  This puts stress on the water column in the form of negative pressure within the xylem- you can think of it like sucking on a straw.  With this water potential system, the plant is able to suck water out of the soil and transport it to different parts of its body.  The water potential is also a component of the nutrient transport system.