Introduction to Cell & Molecular Biology (BIOL121) - Dr. S.G. Saupe (ssaupe@csbsju.edu); Biology Department, College of St. Benedict/St. John's University, Collegeville, MN 56321 |
Membrane Questions
1. The cells of plant seeds store oil in the form of droplets enclosed by membranes. Unlike the cell membrane, the oil-droplet membrane probably consists of a single layer of phospholipids rather than a bilayer. Draw a model for a membrane around an oil droplet. Explain why this arrangement would be more stable than if it were a bilayer.
2. What is the importance of having sugars on the external side of the cell membrane? In other words, why are some membranes sugar-coated? Give one example of how these are used by an organism. What is the technical term for the sugar-coating?
3. Which of the following is TRUE?
4. According to the fluid mosaic model of protein structure, proteins of the membrane are:
5. When a cell membrane is split by freeze-fracture into its outer and inner leaflets, the bumps seen in the electron micrographs are images of :
6. Which of the following factors would increase membrane fluidity?
7. Consider an artificial cell with a semi-permeable membrane that is permeable to simple sugars (glucose, fructose) but not disaccharides (sucrose). If the cell contains an aqueous solution of 0.03 M sucrose and 0.02 M glucose and is then immersed in a beaker containing water and 0.01 M sucrose, 0.01 M glucose and 0.01 M fructose then:
8. If a cell is placed in a solution and it swells, the solution is probably:
Last updated: July 14, 2009 � Copyright by SG Saupe