Q12. Which of the following moves material against a concentration gradient?

1. osmosis
2. diffusion
3. active transport
4. facilitated transport

Q13. Which of the following processes moves molecules using cellular energy?  

1. Osmosis.
2. Diffusion.
3. Pinocytosis.
4. Facilitated transport.

Q14. Which of the following processes would be directly affected by a lack of cellular ATP?  

1. Osmosis.
2. Diffusion.
3. Active transport.
4. Facilitated transport.

Q15. Which of the following will be affected directly if the mitochondria in a cell are not functioning properly?  

1. Absorption of alcohol by the cell.
2. The movement of water into and out of the cell.
3. The movement of oxygen across the cell membrane.
4. The movement of sugar from a low to a high concentration.

Q16. The cell process which uses ATP to bring substances into the cell is  

1. Osmosis.
2. Diffusion.
3. Active transport.
4. Facilitated transport.

Q17. A bacterium is living in a pond where the concentration of sodium ions is 0.005mM. This ion is found in the bacterial cytoplasm at a concentration 0.10 mM. Therefore the sodium ion is probably entering by: 

1. Simple diffusion
2. Facilitated diffusion
3. Passive transport
4. Active transport

Q18. What are the two factors that are responsible for diffusion rate? 

Q19. What are the membrane potentials of living cells? 

Q20. How the opening and closing of ion channels occur in a cell? 

Q21. Explain glucose transporter or GLUT1 with a diagram. 

Q22. What are the different types of mediated transport depending on the thermodynamics of the system? 

Q23. How the mediated transport can be differentiated from non-mediated transport. Explain with a graph. 

References:

1. Baldwin, S. A., J. C. Gorga, and G. E. Lienhard (1981); The monosaccharide transporter of the human erythrocyte. Transport activity upon reconstitution, J. Biol. Chem. 256:3685-3689.
2. Donald Voet, Judith G. Voet, Charlotte W. Pratt (2008); Fundamentals of Biochemistry- Life at the Molecular Level: Chapter 10 Membrane transport, 3rd Edition
3. Joyce J. Diwan (1998-2007); Membrane transport, http://www.rpi.edu/dept/bcbp/molbiochem/MBWeb/mb1/part2/carriers.htm
4. M. Lodish (2003), Molecular cell biology: Chapter 3 Biomembranes and cell architecture, 5th edition
5. M. Lodish (2003); Molecular cell biology: Chapter 7 Transport of ions and small molecules across cell membranes, 5th edition
6. Sui H, han BG, Lee JK, Walian P, Jap Bk. (2001); Structural basis of water-specific transport through the AQP1 water channel, Nature 414:872-878