1. Human Physiology Cells and Their Environment Chapter 3

2. Cells and Their Environment Approximately 70% of the total body water content is found within cells, and is called _______________________. ANSWER

3. Approximately 70% of the total body water content is found within cells, and is called intracellular fluid or cytoplasm. Cells and Their Environment

4. Diffusion ANSWER Which of the following are more likely to diffuse across a membrane? A. Glucose. B. Oxygen and carbon dioxide. C. Proteins. D. All of the above

5. Diffusion Which of the following are more likely to diffuse across a membrane? A. Glucose. B. Oxygen and carbon dioxide. C. Proteins. D. All of the above

6. Diffusion ANSWER Soaking a de-calcified egg in a high fructose solution will cause the egg to A. shrink. B. swell. C. stays the same. D. None of the above.

7. Diffusion Soaking a de-calcified egg in a high fructose solution will cause the egg to A. shrink. B. swell. C. stays the same. D. None of the above.

8. Diffusion ANSWER With respect to the sodium-potassium pump, which of the following is correct? A. 3 Na+ exit cell while 2 K+ enter the cell. B. 3 Na+ enter cell while 2 K+ exit the cell. C. 2 Na+ exit cell while 3 K+ enter the cell. D. 2 Na+ enter cell while 3 K+ exit the cell. D. None of the above.

9. Diffusion With respect to the sodium-potassium pump, which of the following is correct? A. 3 Na+ exit cell while 2 K+ enter the cell. B. 3 Na+ enter cell while 2 K+ exit the cell. C. 2 Na+ exit cell while 3 K+ enter the cell. D. 2 Na+ enter cell while 3 K+ exit the cell. D. None of the above.

10. Cell Membrane Trasport ANSWER Which of the following forms of endocytosis involves the entry of fluid particles into a cell? A. Receptor-mediated. B. Pinocytosis. C. Phagocytosis. D. Ca+2 pump. D. None of the above.

11. Cell Membrane Trasport Which of the following forms of endocytosis involves the entry of fluid particles into a cell? A. Receptor-mediated. B. Pinocytosis. C. Phagocytosis. D. Ca+2 pump. D. None of the above.

12. Oral rehydration therapy is effective in treating chronic diarrhea specifically due to the __________of glucose and Na+ across intestinal cell wall membranes. A. simple diffusion B. facilitated diffusion C. osmosis D. co-transport E. counter-transport ANSWER Cell Membrane Transport

13. Oral rehydration therapy is effective in treating chronic diarrhea specifically due to the __________of glucose and Na+ across intestinal cell wall membranes. A. simple diffusion B. facilitated diffusion C. osmosis D. co-transport E. counter-transport Cell Membrane Transport

14. Which type of passive transport involves movment of particles across a membrane based on fluid pressure? A. Simple diffusion B. Filtration C. Osmosis D. Na+/K+ pump E. Facilitated diffusion ANSWER Cell Membrane Transport

15. Which type of passive transport involves movment of particles across a membrane based on fluid pressure? A. Simple diffusion B. Filtration C. Osmosis D. Na+/K+ pump E. Facilitated diffusion Cell Membrane Transport

16. Diffusion and Osmosis ANSWER Which of the following will result in an increase in diffusion rate across the membrane? A. Higher concentration gradient. B. Freely permeable membrane. C. Less surface area. D. All of the above E. A and B only

17. Diffusion and Osmosis Which of the following will result in an increase in diffusion rate across the membrane? A. Higher concentration gradient. B. Freely permeable membrane. C. Less surface area. D. All of the above E. A and B only

18. ANSWER This ion is primarily responsible for maintaining the resting membrane potential of excitable cells. A. Sodium. B. Potassium. C. Chloride. D. Protein. E. Calcium. Membrane Potential

19. This ion is primarily responsible for maintaining the resting membrane potential of excitable cells. A. Sodium. B. Potassium. C. Chloride. D. Protein. E. Calcium.

20. Membrane Potential In order for an action potential to occur, which of the following channels must open in response to cell stimulation above its thresh-hold potential? A. Ca+2 B. K+ C. H+ D. Na+ E. Cl- ANSWER

21. Membrane Potential In order for an action potential to occur, which of the following channels must open in response to cell stimulation above its thresh-hold potential? A. Ca+2 B. K+ C. H+ D. Na+ E. Cl-

22. Membrane Potential After stimulation exceeding its thresh-hold potential a cell membrane’s potential briefly changes to ___________________________, causing formation of an action potential. A. -30 B. -50 C. -70 D. +30 E. +70 ANSWER

23. Membrane Potential After stimulation exceeding its thresh-hold potential a cell membrane’s potential briefly changes to ___________________________, causing formation of an action potential. A. -30 B. -50 C. -70 D. +30 E. +70

24. Cell Signaling The use of a chemical messenger to transfer information from one cell type to another cell type within a single tissue is referred to as paracrine signaling.

25. Cell Signaling A typical flow of information in a signal transduction pathway would be: A. hormone → second messenger → receptor → biological response B. hormone → second messenger → receptor → biological response C. receptor → second messenger → biological response → G protein D. receptor → G protein → second messenger → biological response ANSWER

26. Cell Signaling A typical flow of information in a signal transduction pathway would be: A. hormone → second messenger → receptor → biological response B. hormone → second messenger → receptor → biological response C. receptor → second messenger → biological response → G protein D. receptor → G protein → second messenger → biological response