a. A human cell is placed in a container of sugar water. Explain what would occur, if the cell membrane is impermeable to sugar.
b. Another cell is placed into a container of sugar water. However, this cell has the capability to allow large molecules such as sugar to pass through. What will occur in this cell when it is placed into the container of sugar water?
c. If you were yo use a really powerful microscope what might you notice about this cell membrane compared to the first one?
d. At first the passage of sugar across the membrane in the cell from Letter B occurs very slowly, but then the sugar starts to pass at a a very fast rate until the balance of sugar in the cell and outside the cell is reached. What caused this to happen, and what is the name given to this process?
a. If the cell membrane is impermeable to sugar, it means that sugar molecules cannot pass through the membrane. In this case, when the cell is placed in a container of sugar water, there would be no movement of sugar into or out of the cell. The concentration of sugar inside the cell would remain unchanged.
b. If the cell has the capability to allow large molecules like sugar to pass through, it means that the cell membrane has transport proteins or channels that facilitate the movement of sugar molecules across the membrane. When this cell is placed in a container of sugar water, the sugar molecules will be able to pass through the membrane into the cell. This is because the cell membrane allows the movement of sugar molecules, resulting in an increase in the concentration of sugar inside the cell.
c. If you were to use a really powerful microscope, you might notice that the cell membrane of the second cell, which allows the passage of sugar, has transport proteins or channels embedded within it. These transport proteins or channels would be visible under the microscope, indicating that the cell membrane has specific structures that enable the movement of large molecules like sugar.
d. The slow passage of sugar across the membrane in the cell from Letter B is likely due to the transport proteins or channels initially needing time to adjust and facilitate the movement of sugar molecules. However, once these proteins or channels become fully active, sugar starts passing at a faster rate. This occurs until the concentration of sugar inside and outside the cell reaches equilibrium, where the movement of sugar molecules into and out of the cell is balanced. This process is known as facilitated diffusion, where transport proteins or channels assist in the passive movement of substances across the cell membrane.
a. If the cell membrane is impermeable to sugar, it means that the sugar molecules cannot pass through the membrane. In this case, when the cell is placed in a container of sugar water, there will be no movement of sugar molecules across the cell membrane. The concentration of sugar inside the cell will remain unchanged.
b. If the cell has the capability to allow large molecules like sugar to pass through, it means that the cell membrane is permeable to sugar. In this case, when the cell is placed in a container of sugar water, the sugar molecules outside the cell will diffuse across the cell membrane and enter the cell. This process is called osmosis.
c. If you were to use a powerful microscope to observe the cell membranes of these two cells, you might notice a difference between them. In the first cell with an impermeable membrane, you would observe that the sugar molecules do not pass through the membrane and there would be no change in the concentration of sugar inside the cell. In the second cell with a permeable membrane, you would observe the movement of sugar molecules across the membrane, leading to a change in the concentration of sugar inside the cell.
d. The passage of sugar across the membrane in the second cell initially occurs slowly because there is a concentration gradient between the sugar solution outside the cell and the sugar concentration inside the cell. However, as sugar molecules continue to move into the cell, the concentration inside the cell increases. Eventually, the concentration of sugar inside and outside the cell reaches equilibrium, at which point the movement of sugar molecules across the membrane balances out, resulting in an equal rate of sugar entering and leaving the cell. This process is known as dynamic equilibrium.