Which of the following statements are correct? Explain your answers. The plasma membrane is highly impermeable to all charged molecules. Channels have specific binding pockets for the solute molecules they allow to pass. Transporters allow solutes to cross a membrane at much faster rates than do channels. Certain H+ pumps are fueled by light energy. The plasma membrane of many animal cells contains open K+ channels, yet the K+ concentration in the cytosol is much higher than outside the cell. A symport would function as an antiport if its orientation in the membrane were reversed (i.e., if the portion of the molecule normally exposed to the cytosol faced the outside of the cell instead). The membrane potential of an axon temporarily becomes more negative when an action potential excites it.

Which of the following statements are correct? Explain your answers. The plasma membrane is highly impermeable to all charged molecules. Channels have specific binding pockets for the solute molecules they allow to pass. Transporters allow solutes to cross a membrane at much faster rates than do channels. Certain H+ pumps are fueled by light energy. The plasma membrane of many animal cells contains open K+ channels, yet the K+ concentration in the cytosol is much higher than outside the cell. A symport would function as an antiport if its orientation in the membrane were reversed (i.e., if the portion of the molecule normally exposed to the cytosol faced the outside of the cell instead). The membrane potential of an axon temporarily becomes more negative when an action potential excites it.

Human Physiology: From Cells to Systems (MindTap Course List)

9th Edition

ISBN:9781285866932

Author:Lauralee Sherwood

Publisher:Lauralee Sherwood

Chapter3: The Plasma Membrane And Membrane Potential

Section: Chapter Questions

Problem 6RE

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Liver cells are in contact with the blood and exchange a variety of substances with the blood plasma (the noncellular part of blood). The concentration of water is equal in the cytoplasm of liver cells and in the blood plasma. Explain this observation in terms of membrane permeability and transport mechanisms. Animal cells typically maintain a higher concentration of Na+ outside the cell and a higher concentration of K+ inside the cell via the Na+-K+ pump. The drug ouabain inhibits the activity of the Na+-K+ pump. A nerve cell is incubated in ouabain. Predict what will happen to the concentrations of Na+ and K+ inside and outside the nerve cell as a result.
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In Chapters 11 & 12, the following examples of membrane transport proteins are given. Fill out the table with the correct answer for that particular transport protein. Type of transport protein (channel or carrier/transporter?) K* leak channel glucose transporter bacteriorhodopsin Na-K pump glucose-Na symport Na-H exchanger Performs active or passive transport? Energy source for movement of solute(s) or ion(s) Direction of movement of solute(s) or ion(s) with respect to the electrochemical gradient Na K* Na glucose Na H' Direction of movement of solute(s) or ion(s) with respect to the membrane crossed Na K₁ Na' glucose Na H' Is the protein a uniport, symport, antiport, or none of the above?
Diffusion and osmosis classification Classify the following characteristics based on whether they are describing diffusion, osmosis, or both. Diffusion Results in an Can occur with equal distribution of solute molecules or without a membrane Always involves the movement of water Requires a semi-permeable membrane Osmosis Involves the movement of gases, ions, and small water soluble molecules Passive form of movement that requires no energy Moves from areas of high concentration to low Both Diffusion and Osmosis Responsible for gas exchange in the lungs concentration A 3 of 15 Next > Cation to open the document "Epicinstaller-13.0.0-fortnite-a8e4f12cada646caa706d8be407be69f (3).msi". tv 22
This cell is permeable to Urea, but not permeable to sucrose. Intracellular impermeant molecules cannot cross the plasma membrane. The bath solution is ‘infinite volume’. Bath Solution: 250 mM Sucrose 250 mM Urea Is this solution Hypoosmotic, Isoosmotic, or Hyperosmotic? Immediately after this cell is placed in the bath will it swell, shrink, or remain the same? Fill in this table for equilibrium conditions for each ion. Consider solute movement ONLY. in (mM) out (mM) Intracellular impermeants Sucrose Urea At equilibrium, will the cell swell, shrink, or remain the same volume? Is this solution hypotonic, isotonic, or hypertonic?
The movement of molecules in and out of a cell is essential to its function. The cell membrane regulates this movement though processes such as diffusion, osmosis, active transport, etc. These activities on the next couple pages are designed to assess your understanding of these processes. Scenario #3 Semi-permeable membrane Охудen Carbon Dioxide Lungs I Blood stream After studying the image above, select the statement(s) that would explain what is likely to happen. Choose ALL that apply. O The carbon dioxide molecules will move into the lungs until equalibrium is reached. O All the carbon dioxide molecules will move into the lungs to be exhaled. O All the oxygen molecules will move from the lungs into the blood stream. O The semipermeable membrane will prevent the movement of either molecule. O The oxygen molecules will move into the blood stream until equalibrium is reached.
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