BIO 12 Lab Quiz 1 COMPLETE SOLUTION

BIO 12 Lab Quiz 1 COMPLETE SOLUTION 1. The driving force for diffusion is .: The kinetic energy of the molecules in motion. 2. .: From high concentration to low concen- tration. 3. Which of the following dialysis membranes has the larges pore size?: 200 MWCO 4. Avogadro's number is a constant for the number of .: molecules 5. Glucose is a six-carbon sugar. Albumin is a protein with 607 amino acids. The average molecular weight of a single amino acid is 135 g/mole. There is no reason to run these solutes at the 20 MWCO because .: Glucose and albumin are both too large to pass. 6. The effect of increasing the concentration of sodium chloride from 9mM to 18mM in the left beaker was to .: Increase the rate of diffusion. 7. Describe the difference between the rate of diffusion seen for sodium and urea.: Urea diffused slowly because it is larger than sodium. 8. Which of the following solutes did not pass through any of the mem- branes?: Albumin 9. When diffusion stops, we say the solution has reached .: Equilibrium 10. Describe two variables that affect the rate of diffusion.: Change in concen- tration and diffusion distance. 11. Why do you think urea was not able to diffuse through the 20 MWCO membrane?: Urea molecular weight is 60.07 and the membrane size only allowed molecules below 20 MWCO. (It was to big.) 12. Describe the results of the attempts to diffuse glucose and albumin through the 200 MWCO membrane.: Glucose was able to pass through the 200 MWCO membrane. 13. Put the following in order from smallest to largest molecular weight: glucose, sodium chloride, albumin, and urea.: Sodium chloride, urea, glucose, and albumin. 14. Molecules need a carrier protein to help them move across a membrane because .: They are lipid insoluble or they are too large. 15. Which of the following is true of facilitated diffusion.: Movement is passive and down a concentration gradient. 16. Examples of solutes that might require facilitated diffusion include .: