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30 Cards in this Set
- Front
- Back
Consider a living plant cell in a living leaf that is not wilted. The solute potential (ψS) of such a cell ________ than that in the fluids surrounding the cell. |
is typically lower |
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The Casparian strip of the endodermis stops water from the ______ before it reaches the stele. |
apoplastic pathway |
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According to the cohesion-tension mechanism of water transport, cohesion occurs because |
water molecules tend to form hydrogen bonds with each other |
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Generally, the energy for pumping protons outside of a plant cell comes most directly from |
ATP |
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Consider a living plant cell in a living leaf that is not wilted. The pressure potential (ψp) of such a cell _______ than that in the fluids surrounding the cell. |
is typically higher |
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Aquaporins are |
channel proteins for water |
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Suppose you discover a mutant plant that cannot actively transport solutes across the tonoplast. Which of the following should you expect? |
the plant will wilt easily |
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The simultaneous movement of Na+ out of a cell against its concentration gradient and protons into a cell with their concentration gradient is best described as an example of |
antiport *anti-salt |
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Which plant organelle stores solutes and plays a major role in maintaining turgor pressure? |
vacuole |
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The simultaneous movement of sucrose into a cell against its concentration gradient and protons into a cell with their concentration gradient is best described as an example of |
symport *Sucrose-Symport |
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The membrane potential refers to the ______ across a cell membrane |
charge difference |
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The principal driving force for movement of water into and through the plant shoot is |
sunlight *driving is easier with sunlight |
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If a living plant cell is placed in a beaker of pure water, it will take up water until |
within the cell (ψp) = -(ψS) |
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Which of the following should you expect to find for a living plant cell in a living plant? |
a cytoplasm that is slightly more negatively charged than the fluid outside the cell *same as a neuron |
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What is the (ψp) of a living plant cell that has ψ = -0.2 MPa and (ψS) = -0.4 MPa? |
(ψp) = 0.2 MPa
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Which of the following is NOT transported in phloem? |
nitrate |
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Active transport in plant root cells requires that those cells have access to O2. Normally there is enough O2 available in air pockets in the soil, but flooded soil has very little O2. Thus, unless they have special adaptations, plants in flooded soil effectively have no active transport in their roots. Which of the following should you expect to occur for trees without special adaptations to flooding after several days in flooded soil? |
wilting of their leaves |
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A plant cell with a (ψp) = 0.2 MPa maintains a constant volume when bathed in a solution that has (ψS) = - 0.2 MPA and is in an open container. What do you know about the cell? |
the cell has a (ψS) = - 0.4 MPA |
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Which of the following generally causes stomata to open? |
a drop in CO2 concentration in leaf air spaces |
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Suppose a living plant cell as (ψp) = 0.4 MPa and (ψS) = - 0.5 MPa. If the plant cell is placed into a beaker filled with a solution with (ψ) = (ψS) = - 0.9 MPa, then the cell should |
lose water until its (ψ) = (ψ) of the solution |
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Stomata open when K+ concentration in guard cells _______, followed by water _______ the guard cells by osmosis. |
increases, entering |
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Water that moves through living cells in a root is following the |
transmembrane and symplastic pathways |
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Water that moves through nonliving regions of root, such as air spaces in root tissue, is following the |
apoplastic pathway |
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Under which condition would you expect essentially no transpiration to occur? |
100% relative humidity |
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Which of the following DOES NOT have a major effect on the rate of transpiration? |
daily fluctuations in atmospheric carbon dioxide concentrations |
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The principal driving force for guttation is |
root pressure |
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Most leaf cells are no more than _____ from a xylem vein. |
half a millimeter |
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Most mineral ions that plants need are |
moved into the symplast via active transport |
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Suppose a living plant cell has (ψ) = (ψS) = - 0.5 MPa. If the plant cell is placed into a beaker and filled with a solution with (ψ) = 0, then the cell should |
take up water until within the cell (ψp) = - (ψS) |
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Stomata are opened when _____ guard cells and they become ______. |
active transport pumps H+ out of; turgid |