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6 Cards in this Set
- Front
- Back
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What is active transport? |
The movement of molecules and ions across a membrane, from a low to high concentration, against a concentration gradient (via carrier proteins). |
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State four processes which involve active transport. |
(1)Protein synthesis. (2)Muscle contraction. (3)Nerve impulse transmission. (4)Absorption of mineral salts in plant roots. |
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Why must active transport occur in the presence of oxygen? |
Because active transport requires energy provided by ATP - ATP is made by aerobic respiration, for which oxygen is a reactant. |
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How does cyanide affect active transport? |
Cyanide is a respiratory inhibitor, which prevent aerobic respiration and thus the production of ATP . Therefore, cyanide can reduce or even halt active transport. |
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What would a graph of concentration difference (x-axis) against rate of active transport (y-axis) look like, and why?
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There would be a initial steep rise, and then a leveling-off. This leveling-off would occur, because all the carrier proteins would be in use - a limiting factor. |
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What would a graph of concentration difference (x-axis) against rate of active transport (y-axis) look like if cyanide was added, and why?? |
There would be a steep immediate drop, the steepness depending on how much cyanide was added. |
