Key Terms (1 point each). Fill in the blank with the proper term. Each term may be used only once.

Transcription

1 CHM60 Takehome Test 3 Form Student Page 1 of 6 Key Terms (1 point each). Fill in the blank with the proper term. Each term may be used only once. Acid Active transport Alpha helix Beta pleated sheet Buffer Chemical equilibrium Crenation Endothermic Facilitated transport Fibrous protein Globular protein ph Prosthetic group Solute Weak electrolyte 1. is the transport of ions or small molecules across the cell membrane in a direction opposite to diffusion. Involves an integral membrane protein and requires energy. 2. is the diffusion of ions or small polar molecules across the cell membrane with the assistance of a protein. 3. A is a substance that weakly conducts electricity because it only partially ionizes in aqueous solution. 4. A is a substance that dissolves in water and produces hydrogen ions (H+) according to the Arrhenius theory; or it is a proton donor, according to the Bronsted-Lowry theory. 5. A is a solution consisting of a weak acid and its conjugate base or a weak base and its conjugate acid that resists a change in ph when small amounts of acid or base are added. 6. is a state where the rate of formation of products and the rate of formation of reactants are balanced. 7, An reaction is a reaction that absorbs energy in the form of heat from its surroundings. 8. is a measure of the H 3 O+ concentration in a solution. 9. The is a secondary protein structure with a zig-zag structure resembling a folded fan. 10. A has a roughly spherical tertiary structure that typically has nonpolar amino acid side chains clustered in its interior and polar amino acid side chains on its surface.

2 CHM60 Takehome Test 3 Form Student Page 2 of 6 Multiple Choice (2 points each). Mark the best answer for each question. There is only one answer. 11) Which of the following statements best describes the phrase "like dissolves like"? A) The only true solutions are formed when water dissolves a polar solute. B) A solvent and a solute with similar intermolecular forces will easily make a solution. C) The only true solutions are formed when water dissolves a nonpolar solute. D) A solvent will dissolve a solute that has a similar mass. 12) In general, the solubility of in water decreases as temperature increases. A) liquids B) solids C) gases D) none of these 13) A water solution of sodium chloride is a good conductor of electricity. Due to this property, table salt is classified as a(n): A) weak electrolyte B) strong electrolyte C) non-electrolyte D) semi-electrolyte 14) What volume of 8.25 M NaOH solution must be diluted to prepare 2.40 L of M NaOH solution? A) 39.6 L B) L C) 438 ml D) 145 ml 15) In order to prevent the process of either crenation or hemolysis with red blood cells an intravenous solution concentration should be to the concentration of blood. A) hypotonic B) hypertonic C) isotonic D) all of these 16) An Arrhenius acid is defined as a substance which: A) acts as proton acceptor in any system B) acts as proton donor in any system C) decreases [H+] when placed in water D) increases [H+] when placed in water 17) Which of the following is a weak acid? A) H3PO4 B) HNO3 C) NH3 D) OH- 18) The following reaction is exothermic. Which of the following will drive the reaction to the right (towards products)? CH4 (g) + 2 O2 (g) CO2 (g) + 2 H2O (g) A) A decrease in temperature B) An increase in temperature C) The removal of CH4 D) The addition of CO2 19) Which of the following does not represent a conjugate acid-base pair? A) H3O+/H2O B) HCN/CN - C) HCl/Cl - D) HC2H3O2/OH - 20) In an acidic solution, ph is and [H3O+] is. A) = 7, 1 x 10-7 M B) > 7, < 1 x 10-7 M C) < 7, > 1 x 10-7 M D) < 7, < 1 x 10-7 M

3 CHM60 Takehome Test 3 Form Student Page 3 of 6 21) The isoelectric point of an amino acid is defined as: A) the ph at which the amino acid exits in the zwitterion form B) the ph at which it exists in the basic form C) the ph at which it exists in the acidic form D) the ph equals the pka 22) When a person hyperventilates the condition is known as: A) respiratory acidosis B) respiratory alkalosis C) metabolic acidosis D) metabolic alkalosis 23) Which of the following amino acids is an essential amino acid in the diets of children? A) Arginine B) Lysine C) Asparate D) Glycine 24) The structure among the following that represents an amide (protein) bond is: A) B) C) D) 25) The sequence of amino acid is considered to be the structure of a protein. A) secondary B) tertiary C) quaternary D) primary 26) Heavy metals such as Pb+2 or Hg+2 denature proteins by reacting with: A) the proline residues B) the OH group of tyrosine residues C) the SH group of cysteine residues D) the NH2 group of glutamine 27) Which of the following proteins has a distinctive Y-shape? A) Hemoglobin B) Collagen C) Antibodies D) Integral protein

4 CHM60 Takehome Test 3 Form Student Page 4 of 6 Short Answer (2 points each). Write your answer in the space provided. Please write legibly! 28) Explain the difference between active and facilitated transport across a cell membrane. 29) Indicate whether the following solutions are acidic, basic or neutral. For each concentration calculate the ph of the solution. A) [H+] = M B) [H+] = M

5 CHM60 Takehome Test 3 Form Student Page 5 of 6 30) What is the secondary structure of a protein? Distinguish between the two major types of secondary structures.

6 CHM60 Takehome Test 3 Form Student Page 6 of 6