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Why water potential always negative in uptake of water in plant?
Wiki User
∙ 10y ago
To follow the Law of diffusion.
Wiki User
∙ 10y ago
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How do you explain a plant cell in water?
Turgid. Which, it should be noted is normal for a plant cell due to their near constant uptake of water.
How would you use the photometer to find the effect of wind on the water uptake by the shoot?
If you are referring to a the rate of water uptake in plants, then a live plant stem is placed in one end of the uptake photometer which is filled with water by a reservoir and tap. at the other end of the photometer there is a scale with an air bubble. Over time, as the plant takes in water, the air bubble will move along the scale and this can be used to work out how much water the plant is using. dont know if this will be of any help :)
Why does overcrowding affect the uptake of water by a plant?
Overcrowded plants have to compete with neighboring root systems for water as well as nutrients.
How does the central vacuole in a plant cell arise?
There are many small vacuoles present in a developing plant cell . they merge with each other during ontogony of cell .this results in formation of a large central vacuole in plant cell .Vacuoles grow by uptake of waer .
Chloroplasts change sunlight to what?
Oxygen and sugar (glucose). However, sunlight alone cannot produce this. Water and carbon dioxide must also be present for the plant to uptake.
Do plants grow downwards?
No, plants do not always grow downward. Plant roots always grow downward due to positive gravitropism or positive geotropism. Plant shoots always grow upwards due to negative gravitropism or negative geotropism.
What process is most important in the expansion of plant cells?
Water Uptake is most important in the expansion of plant cells.
What factors affect water uptake by plant cells?
soil humidity, air humidity, soil structure, pH, nutrients availability, temp,
How do you calculate the rate of water uptake by a plant?
Divide the sum of measurmeants by number of measurments
How do you explain a plant cell in water?
Turgid. Which, it should be noted is normal for a plant cell due to their near constant uptake of water.
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.
Do plants grow faster and salt water or water?
Salt water changes the osmotic potential around the roots of the plants, preventing osmosis and the uptake of water and nutrients. Unless plants have special adaptations to cope with this (such as halophytes), the plant eventually wilts and dies. Salt also changes the pH of the soil, which inhibits the uptake of certain nutrients, resulting in deficiencies, and eventually possible death
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
What job do the roots of a plant do?
Provides anchorage for the plant. Provides a mechanism and increased surface area for the uptake/ absorption of water and minerals for the plant.
How would you use the photometer to find the effect of wind on the water uptake by the shoot?
If you are referring to a the rate of water uptake in plants, then a live plant stem is placed in one end of the uptake photometer which is filled with water by a reservoir and tap. at the other end of the photometer there is a scale with an air bubble. Over time, as the plant takes in water, the air bubble will move along the scale and this can be used to work out how much water the plant is using. dont know if this will be of any help :)
Is crop uptake the same as crop rotation?
No. Crop uptake is the water and nutrients the plant moves from its roots up to its leaves, and crop rotation is changing which crop is grown in a given field from one crop cycle to the next.
What is plant uptake?
This is when the water from the soil is taken by the roots of plants and used to make the plant grow. Then the water cycle starts all over again. Hope this helps you
