Name ______Per ______

UNIT III STUDY GUIDE

Description Name of Cell Structure 1. Double phospholipid bilayer; surrounds and protects DNA 2. Membranous network; site of protein processing and transport 3. Membrane surrounding central vacuole in plant cells 4. Sacs filled with hydrolytic enzymes; only found in animal cells 5. Selectively-permeable membrane found in all cells 6. Site of photosynthesis in plant cells 7. Cytoskeleton component involved in cell motility, movement of DNA during cell division 8. Membrane-lined openings between plant cells; allows for movement of water, ions, proteins 9. Site of protein synthesis; found in all cells (pros & euks)

10. Sacs containing catalase; catalyze breakdown of H2O2 11. Cell postmaster; modifies, packages, ships biomolecules 12. Cell gel 13. Flattened discs found in chloroplasts 14. Cytoskeleton component that maintains the integrity of nucleus; less movable than others 15. Control center of eukaryotic cell; not found in prokaryotic cells 16. Site of oxidative respiration; site of most ATP production in cells 17. Outer boundary found in plant, fungal, bacterial cells 18. Site of lipid production, detoxification, glycogen breakdown, Ca2+ storage 19. Storage sac; important in maintaining turgor in plant cells 20. Stack of thylakoids 21. DNA wrapped in protein 22. Actin; proteins involved in cytokinesis in animal cells, formation of microvilli 23. Openings in nuclear envelope to allow for passage of RNA, ribosomes 24. Site of ribosome production 25. Pair of microtubule bundles involved in cell division in animal cells only

26. List the structures listed above that are also found in a prokaryotic cell.

CELL TRANSPORT, TONICITY, & WATER POTENTIAL

1. A cell is placed in a solution and swells. The solution is: a. isotonic to the cell b. hypotonic to the cell c. hypertonic to the cell

2. A cell with an internal concentration of 0.3 M is placed in a beaker containing a solution that is 0.5 M. The cell is: a. isotonic to the solution b. hypotonic to the solution c. hypertonic to the solution

3. A cell with an internal concentration of 0.3 M is placed in a beaker containing a solution that is 0.5 M. Assume the solution in the beaker is sucrose. Initially, what is the water potential of the beaker if the temperature is 24º C?

4. Now assume the beaker solution is NaCl and the temperature is still 24º C, what is the water potential? 5. Determine the water potential of a cell if ΨP = 0.3 MPa and ΨS = - 0.5 MPa.

6. If the cell described in question 5 is placed in a beaker of distilled water, which direction would the water move?

7. Calculate the pressure potential in a cell if ΨW = 0 and ΨS = - 0.2.

8. If the cell described in question 7 is placed in a beaker of distilled water, which direction would the water move?

9. What is the water potential of the distilled water in the beaker? Pressure potential? Solute potential?

10. The optimum environment for an animal cell is ______relative to the cell.

11. The optimum environment for a plant cell is ______relative to the cell.

12. You are an agri-science consultant to a large corporate farm that raises 7000 acres of wheat on desert land adjoining the Mediterranean Sea. Just before the wheat matures, all the wells used for irrigation water run dry. The farm manager wants to irrigate the fields with water drawn from the Mediterranean, From previous tests, you know that the average ΨS of root tissue taken from the wheat fields is – 11.13 bars. You test the seawater and determine its solute potential to be – 24.26 bars. What will you advise the farmer and why?

13. A freshwater fish is mistakenly placed in a saltwater aquarium. What will happen and why?

14. Which of the following would be least likely to diffuse through a cell membrane without the help of a transport protein? a. a large polar molecule b. a large non-polar molecule c. a small polar molecule d. a small non-polar molecule e. Any of the above would easily diffuse through the membrane.

15. Red blood cells shrivel when placed in a 10% sucrose solution. When first placed in the solution, the solute concentration of the cells is ______the concentration of the sucrose solution. After the cells shrivel, their solute concentration is ______the concentration of the sucrose solution.

16. Watering a houseplant with too concentrated a solution of fertilizer can result in wilting because the fertilizer causes the soil to become ______relative to the plant.

17. Refer to question 16. a. Which has the greater water potential . . . the soil after watering with fertilizer or the plant cells? ______b. Which has the greater concentration of solute? ______c. How does ΨS compare for each? ______

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 filled with a solution of 2.0 M sucrose and 1.0 M glucose. Side B is filled with 1.0 M sucrose and 2.0 M glucose.

18. Initially the solution in side A, with respect to that in side B, is ______.

19. After the system reaches equilibrium, what changes are observed? a. The water level is higher in side A than side B. b. The water level is higher in side B than side A. c. The molarity of glucose is higher in side A than in side B. d. The molarity of sucrose has increased in side A. e. Both a and c have occurred.

20. During the period before equilibrium is reached, which molecule(s) will show net movement through the membrane? a. water b. glucose c. sucrose d. water and sucrose e. water and glucose ………………………………………………………………………………………………………………………………………………. CELL MEMBRANE STRUCTURE & FUNCTION Identify the following parts of the cell membrane and the function of each part.  Hydrophilic region of integral protein  Hydrophobic region of integral protein  Glycolipid  Glycoprotein  Cholesterol  Peripheral protein  Phospholipid bilayer