Exam 7: Membrane Structure and Function

Use the diagram of the U-tube in Figure 7.2 to answer the questions that follow. The solutions in the two arms of this U-tube are separated by a membrane that is permeable to water and glucose but not to sucrose. Side A is half filled with a solution of 2 M sucrose and 1 M glucose. Side B is half filled with 1 M sucrose and 2 M glucose. Initially, the liquid levels on both sides are equal. -A patient has had a serious accident and lost a lot of blood. In an attempt to replenish body fluids, distilled water, equal to the volume of blood lost, is transferred directly into one of his veins. What will be the most probable result of this transfusion?

Use the diagram of the U-tube in Figure 7.2 to answer the questions that follow. The solutions in the two arms of this U-tube are separated by a membrane that is permeable to water and glucose but not to sucrose. Side A is half filled with a solution of 2 M sucrose and 1 M glucose. Side B is half filled with 1 M sucrose and 2 M glucose. Initially, the liquid levels on both sides are equal. -After the system reaches equilibrium, what changes are observed?

Use the diagram of the U-tube in Figure 7.2 to answer the questions that follow. The solutions in the two arms of this U-tube are separated by a membrane that is permeable to water and glucose but not to sucrose. Side A is half filled with a solution of 2 M sucrose and 1 M glucose. Side B is half filled with 1 M sucrose and 2 M glucose. Initially, the liquid levels on both sides are equal. -A cell whose cytoplasm has a concentration of 0.02 molar glucose is placed in a test tube of water containing 0.02 molar glucose. Assuming that glucose is not actively transported into the cell, which of the following terms describes the tonicity of the external solution relative to the cytoplasm of the cell?

Which of these are attached to the extracellular matrix?

In most cells, there are electrochemical gradients of many ions across the plasma membrane even though there are usually only one or two electrogenic pumps present in the membrane. The gradients of the other ions are most likely accounted for by

For the following questions, match the labeled component of the cell membrane (Figure 7.1) with its description. -peripheral protein

An artificial cell consisting of an aqueous solution enclosed in a selectively permeable membrane is immersed in a beaker containing a different solution. The membrane is permeable to water and to the simple sugars glucose and fructose but impermeable to the disaccharide sucrose. (A)Draw solid arrows to indicate the net movement of solutes into and/or out of the cell. (B)Is the solution outside the cell isotonic, hypotonic, or hypertonic? (C)Draw a dashed arrow to show the net osmotic movement of water, if any. (D)Will the artificial cell become more flaccid, more turgid, or stay the same? (E)Eventually, will the two solutions have the same or different solute concentrations?

What kinds of molecules pass through a cell membrane most easily?

The following information should be used to answer the following questions. Cystic fibrosis is a genetic disease in humans in which chloride ion channels in cell membranes are missing or nonfunctional. -Chloride ion channels are membrane structures that include which of the following?

When biological membranes are frozen and then fractured, they tend to break along the middle of the bilayer. The best explanation for this is that

If a membrane protein in an animal cell is involved in the cotransport of glucose and sodium ions into the cell, which of the following is most likely True?

When a plant cell, such as one from a peony stem, is submerged in a very hypotonic solution, what is likely to occur?

Water passes quickly through cell membranes because

Which of the following is a reasonable explanation for why unsaturated fatty acids help keep any membrane more fluid at lower temperatures?

White blood cells engulf bacteria through what process?