1. #1 Which part of all cells is responsible for regulating which substances enter or exit the cell? a. cell wall b. nuclear membrane c. cell membrane d. nuclear wall

2. #2 Which of the following best describes the cell membrane? a. completely permeable b. watertight c. selectively permeable d. protectively permeable

3. #3 The transport of materials in and out of a cell helps an organism maintain an internal stability known as… a. facilitation b. fermentation c. differentiation d. homeostasis

4. #4 All forms of passive transport are driven by… a. energy from the cell in the form of ATP b. ion channels c. the kinetic energy of molecules d. carrier proteins

5. #5 If the molecular concentration of a substance is the same throughout a space, the substance… a. has a large concentration gradient b. is in equilibrium c. has a small concentration gradient d. will undergo active transport

6. #6 Which of the following is NOT a factor used to determine the ability of a molecule to diffuse across the cell? a. size b. solubility c. type d. all are factors used

7. #7 Which of the following substances can pass through the cell by diffusion? a. sodium ions b. chlorine ions c. glucose d. oxygen

8. #8 The diffusion of water is called… a. facilitated diffusion b. diffusion through ion channels c. osmosis d. simple diffusion

9. #9 For the following, determine if the statement is referring to a HYPOTONIC, HYPERTONIC, OR ISOTONIC solution. It’s prefix means “the same” Occurs when concentration of solutes outside the cell is lower than in the cytosol Water moves out & the cell shrinks in this type of solution

10. #10 For the following, determine if the statement is referring to a HYPOTONIC, HYPERTONIC, OR ISOTONIC solution Water diffuses in and out at equal rates & cell remains the same size in this type of solution It’s prefix means “less” Occurs when the concentration of solutes outside the cell is higher than in the cytosol

11. #11 For the following, determine if the statement is referring to a HYPOTONIC, HYPERTONIC, OR ISOTONIC solution It’s prefix means “more” Water moves in & cell gets larger in this type of solution Occurs when the concentration of solutes outside the cell is equal to the concentration of solutes inside the cell

12. #12 A structure that can remove excess water from unicellular organisms in hypotonic environments is called… a. carrier protein b. contractile vacuole c. ion channel d. solute pump

13. #13 Plants cells are often found in hypotonic environments. The influx of water causes the plant cell to swell, exerting pressure the cell wall. This pressure is called… a. wall pressure b. membrane pressure c. botanic pressure d. turgor pressure

14. #14 When a human red blood cell is placed in a hypotonic environment, it will a. undergo cytolysis b. be at equilibrium c. undergo plasmolysis d. shrink

15. #15 Which of the following is NOT a characteristic of facilitated diffusion? a. Requires energy b. Moves substances down a concentration gradient c. It requires no energy input d. It involves a change in the shape of its carrier

16. #16 Facilitated diffusion is often used to transport… a. molecules too small to diffuse b. water c. molecules not soluble in lipids d. ions

17. #17 Na+ ions enter cells by a. diffusion b. facilitated diffusion c. osmosis d. diffusion through ion channels

18. #18 Which of the following is NOT an example of ACTIVE transport? a. facilitated diffusion b. endocytosis c. exocytosis d. cell membrane pumps

19. #19 Cell membrane pumps refers to carrier proteins involved in which type of transport? a. passive b. active c. simple d. aggressive

20. #20 The sodium-potassium pump creates an electrical gradient by placing _____ Na+ outside the cell membrane and _____ K+ inside the cytosol. a. 2; 3 b. 3; 2 c. 6; 9 d. 9; 6

21. #21 Molecules that are too large or fluids can be moved through the membrane and transported by… a. osmosis b. lipid carriers c. ion channels d. endocytosis

22. #22 Pinocytosis and phagocytosis differ in that…. a. One is a passive transport, while the other is an active transport mechanism b. One is a type of exocytosis, while the other is a type of endocytosis c. One transports fluids, while the other transports solid particles d. One is a type of facilitated diffusion, while the other is a membrane pump

23. #23 Cells in animals that ingest bacteria and viruses that invade the body are called… a. phagocytes b. leukocytes c. lysosomes d. vesicles

24. #24 Ridding the cell of material by discharging it from sacs at the cell surface is called… a. phagocytosis b. exocytosis c. pinocytosis d. endocytosis

25. #25 Describe the differences between active and passive transport. Discuss both energy requirements and movement relative to the concentration gradient.

26. #26 Explain in terms of osmosis, why you should not drink salt water if you are stranded out at sea.

27. #27 Arrange the 6 steps of the sodium- potassium pump in order. Then describe each step in words.