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How does active transport of glucose cause osmosis?
Osmosis is the transport of water across semi permeable plant membrane. When glucose molecules actively transport to the plant they lower the water potential of the plant and therefore water moves in to balance that. This is how active transport assists osmosis.
What is plasmolysis and why is it important to plant cells?
Plasmolysis refers to the contraction of the protoplast of a plant cell as a result of loss of water from the cell. The plasma membrane moves away from the cell wall due to loss of water through osmosis. Osmosis on its part, is the movement of water molecules from a region of high water potential to a region of lower water potential through selectively permeable membrane.
Why water potential always negative in uptake of water in plant?
To follow the Law of diffusion.
What would you expect would happen to a plant if you watered it with very salty water?
Water potential of the water inside the cells is higher that the water potential of the water outside the cells. (That would means the concentration of "pure" water inside the cells are higher than that outside the cells) Water moves from an higher water potential to an lower water potential. Thus Plasmolysis of the cells will take place. Which means the Nucleus,Vacuole and all the other cellular material will move from the inside of the cell to the outside.
What is the difference between water potential and chemical potential of water?
Plant water potential  w (psi) is a measure of physical(thermo - dynamic), the free energy expression of the amountof water (J mol-1), and accordingly the ability to perform work. The chemical potential of water μw is a relative value,expressed the free energy difference (J mol-1) between the chemical potential of water in a given biological (eg leaf) anddistilled water potential found in the same temperature andatmospheric pressure as a biological system. The chemical potential μ of distilled water * w is the maximum chemical potential of water in the plant and in an agreed value is set to 0. Presence of solvent water, or the existence of water stress reducing advice in the chemicalpotential of water and therefore, the chemical potential ofwater in solution or in the sacrum has a negative value. Water movement will take place spontaneously (without theneed to invest energy) from which the chemical potential ofwater is higher where the chemical potential of water is lower.
Why is the water potential of distilled water higher than the water potential of the cytoplasm of the cell?
distilled contain no solute. so, its water potential is constantly 0. plant cell carry out photosynthesis continuously to produce sugar. thus, cytoplasm of plant cell always contain solute that lower the water potential of cytoplasm.
What is water potential gradient?
similar to potential energy, water flows down a gradient from higher potential to lower potential. Higher potential is generally in the soil/roots and lower potential is at the leaves/atmosphere. The water has potential to flow down the gradient
How does active transport of glucose cause osmosis?
Osmosis is the transport of water across semi permeable plant membrane. When glucose molecules actively transport to the plant they lower the water potential of the plant and therefore water moves in to balance that. This is how active transport assists osmosis.
If a plant cell has a lower water potential than its surrounding environment and if pressure is equal to zero is the cell hypertonic or hypotonic to its environment?
water potential measures the tendency of water to move from one region to another. In the case of osmosis occurring through the membrane of a plant cell, the water potential is the sum of the solute potential and the pressure potential.The question states the pressure potential is nil. Therefore, the water potential is a direct measure of the solute potential.The question also states that the water potential within the cell is lower than that of its surroundings. This means the solute potential within the cell is also lower than that of its surroundings Hence, there is more solutes outside the cell and less solutes inside the cell.This type of solute gradient will cause solvent to move out of the cell. Therefore the cell is hypotonic to its environment.
How does watering a plant with sugar water effect the plant?
Watering a plant with sugar water will usually harm it because it makes soil water less available to the plant. In technical terms, it lowers the water potential of the soil water by lowering the osmotic potential.
When does water potential decrease?
The water potential is really just the sum of the pressure potential and the solute potential. Obviously, then, lower pressure potential would lower the water potential, and so would lower solute potential. To lower the solute potential, the moles of the solute would actually have to increase. This probably seems backwards, but the equation for solute potential is -iCRT (where C is moles/liter, for some reason). Because there's a negative sign, the more moles you have, the less the solute potential is. Hopefully that helps.
What is plasmolysis and why is it important to plant cells?
Plasmolysis refers to the contraction of the protoplast of a plant cell as a result of loss of water from the cell. The plasma membrane moves away from the cell wall due to loss of water through osmosis. Osmosis on its part, is the movement of water molecules from a region of high water potential to a region of lower water potential through selectively permeable membrane.
What is the new water potential of a plant cell of water potential 500kPa after immerse into pure water?
Water potential is the potential energy of water in a system (eg a solution or a cell) compared with pure water under the same conditions. The value of the water potential depends mainly on two factors: 1) The presence of dissolved solutes. Solutes dissolved in the water reduce the energy of the water molecules, and so lower the water potential. This happens because the solute molecules attract the water molecules and reduce their movement. The component of water potential due to solutes is called the solute potential of the solution. 2) The presence of an excess pressure, above that of normal atmospheric pressure. Pressure increases the movement of the water molecules and so increases their energy, thus increasing the water potential. The component of water potential due to pressure is called the pressure potential of the solution. The total water potential of a solution is the sum of the solute potential and pressure potential water potential = solute potential + pressure potential The pressure potential can be positive or negative. An additional pressure on the solution will be positive and increase the pressure potential. If the solution is subject to a reduced pressure (a negative pressure or suction) the pressure potential will be negative and will reduce the water potential. The solute potential is always negative and so always reduces the water potential. Pure water is given a water potential of zero (similar to the way in which the freezing point of water is given a value of 0o Celsius). So anything which reduces the energy of the water molecules (such as dissolving a solute) will reduce the water potential to below zero, and so will be negative. The movement of water depends on the difference in water potential between two systems eg two adjacent cells, or a cell and the surrounding solution. This difference is called the water potential gradient. Water will always move from the higher to the lower water potential ie down the water potential gradient. In osmosis, the two solutions involved are often at atmospheric pressure. In this case it is only the difference in solute concentration which determines the direction of water movement. Water moves from the dilute solution to the concentrated solution. The concentrated solution has a higher concentration of dissolved particles, and so has a lower solute potential than the dilute solution. Since the pressure potential is zero (no excess pressure), the water potential is equal to the solute potential. Water will therefore move from the higher water potential (ie the dilute solution) to the lower water potential (ie the more concentrated solution), down the water potential gradient. It is possible for the pressure potential to counteract the solute potential. For example, if a solute (eg salt) is added to pure water, the water potential will be reduced to a negative value. If the solution is then put under extra pressure eg in a syringe, the positive pressure potential can raise the total water potential above zero ie give it a positive value. This happens especially in plant cells, where the cell wall prevents an increase in volume of the cell. So if water enters by osmosis the extra water molecules cause the pressure inside the cell to increase. This intracellular pressure in a plant cell is called the turgor pressure. For more information see: http://en.wikipedia.org/wiki/Water_potential http://www.colorado.edu/eeb/courses/4140bowman/lectures/4140-07.html http://www.phschool.com/science/biology_place/labbench/lab1/watpot.html
Why water potential always negative in uptake of water in plant?
To follow the Law of diffusion.
What determines the direction of Electric?
The potential difference. The electrons flows from a lower potential to a higher potential. The electric current flows in the opposite direction. The electric field's direction is always from a higher potential to a lower potential. Its kind of like a waterfall. The water always falls down not up. It goes from a higher potential to a lower potential.
What would you expect would happen to a plant if you watered it with very salty water?
Water potential of the water inside the cells is higher that the water potential of the water outside the cells. (That would means the concentration of "pure" water inside the cells are higher than that outside the cells) Water moves from an higher water potential to an lower water potential. Thus Plasmolysis of the cells will take place. Which means the Nucleus,Vacuole and all the other cellular material will move from the inside of the cell to the outside.
What facts about osmosis?
Osmosis is the process where Water Molecules move from a solution with a Higher Water Potential to a solution with a Lower Water Potential through a Partially Permeable Membrane.
