Health Science Module 3 Organic Chemistry Lab 3

Transcription

1 Health Science Module 3 Organic Chemistry Lab 3 All questions on the quiz will come from the Chemistry of Life exercises, and the Lab 3 Worksheet Chemistry of Life Exercise: o Click on the Chemistry of Life link to the Lab Web page o Click on the Carbohydrates link o Participate in all of the lessons in the carbohydrates section o Using your Study Notes, PowerPoint Slides, Textbook, and what you ve learned from the Chemistry of Life tutorial, answer the quiz questions dealing with carbohydrates on your worksheet o Click on Lipids o Participate in all of the lessons in the lipids section o Using your Study Notes, PowerPoint Slides, Textbook, and what you ve learned from the Chemistry of Life tutorial, answer the quiz questions dealing with carbohydrates on your worksheet o Click on the Proteins o Participate in all of the lessons in the proteins section o Using your Study Notes, PowerPoint Slides, Textbook, and what you ve learned from the Chemistry of Life tutorial, answer the quiz questions dealing with carbohydrates on your worksheet Hthsci 1110 Module 3 Lab Worksheet

2 Health Sciences 1110 Module 3-Organic Chemistry Worksheets Carbohydrates Quiz Questions 1. Chemical compounds that contain sugar(s): a. May store energy b. May protect cells c. May store hereditary information d. Both (b) and (c) e. (a), (b), and (c) 2. Sugars with the formula CnH2n0n can have: a. Hydrogen (H) atoms covalently bound to the carbon (C) of a C=0 group b. Carbon (C) atoms which are covalently bound to three H atoms c. The formula C3H6O3 d. Both (a) and (c) e. Both (b) and (c) 3. What is the LEAST that two molecules can differ, and still be called different kinds of sugars? a. One is a ring, the other is linear b. The numbers of C atoms differ c. The orientation of an OH group differs d. The location of the carbonyl group differs 4. The alpha and the beta forms of glucose, found in starch and cellulose, differ in: a. Whether the molecules is a ring or an open chain b. How one of the OH groups is oriented c. Whether the ring contains five or six C atoms d. Whether the first C atom is bound to one or two O atoms 5. Which of these statements is true of sucrose? a. It s a disaccharide b. It contains glucose c. It s a table sugar d. Both (a) and (c) e. (a), (b) and (c)

3 6. Cellulose is: a. The third most abundant organic compound in the world b. Made with glucose that has the beta ring form c. A branching polymer d. A component of crab shell e. All of the above 7. Glycogen: a. Occurs in chloroplasts and stores energy b. Is stronger, weight for weight, than steel c. Contains several kinds of sugars d. Occurs in animal cells and has branches Lipids Quiz Questions 1. What do fats, steroids, and waxes have in common? a. Moderate polarity b. Low solubility in water c. They occur in membranes d. Both (a) and (c) e. Both (b) and (c) 2. In making fat s, and fatty acids combine via dehydration synthesis to form triglycerides plus : a. Glucose; phosphate b. Esters; phosphate c. Esters; water d. Phosphate; glycerol e. Glycerol; water 3. Triglycerides vary with respect to the number of: a. hydrocarbon tails b. atoms in the tails c. Double bonds in the tails d. All of the above. e. Both (b) and (c)

4 4. A food company hydrogenated a barrel of fat. The treatment: a. Made the fat less fluids b. Made the fat less saturated c. Lengthened the fat tails d. Put more bends (kinks) in the fat tails e. Both (a) and (b) 5. The most unsaturated fats have: a. The most double bonds b. The longest hydrocarbon tails c. The shortest hydrocarbon tails d. The fewest double bonds e. The highest ratio of H to C 6. To find the best source of phospholipids, look at: a. Storage droplets b. Cell membranes c. Surfaces of leaves d. Cell walls e. Cholesterol 7. Which statement is true of phospholipids? a. Their synthesis uses fatty acids b. Some of their tails have double bonds c. They all ionize (are polar) d. All of the above e. Both (a) and (b) 8. Which lipid is most amphipathic? a. Cholesterol b. Fat c. Phospholipids d. Wax e. Triglyceride Protein Quiz Questions 1. Which biological activity does NOT directly involve proteins? a. Defending cells against viruses b. Sensing light c. Breaking food polymers into smaller molecules d. Changing the shape of a cell ; proteins are involved in all of them

5 2. A biochemist modified a protein so the amino acid lysine occurred where the amino acid aspartic acid previously occurred. This change would: a. Alter the protein s secondary structure without affecting the primary structure b. Alter the protein s tertiary structure c. Affect the protein s backbone d. Both (b) and (c) e. (a), (b), and (c) 3. The helical foldings of proteins are stabilized mainly by bonds between. a. S = S bonds b. Side chains c. Hydrogen bonds d. Water molecules e. Ionic groups 4. What do the three main forces that stabilize protein tertiary structure have in common? a. They involve the side chains b. They involve the water around the protein c. They are weaker than covalent bonds d. Both (a) and (b) e, Both (a) and (c) 5. Among the forces that stabilize protein tertiary structure, hydrogen bonds are especially important because they are: a. Stronger than other forces b. More resistant to environmental disturbance than other forces c. More associated with side chains than other forces d. Less associated with the backbone than other forces e. More numerous than the other forces 6. When a protein has been unfolded enough to lose its function, the protein has been: a. Denatured b. Distempered c. Hydrolyzed d. Metastasized

6 7. Why don t cells rely more on disulfide bridges to stabilize the folding of proteins? a. Most proteins have no more room for additional disulfide bridges b. Disulfide bridges are too weak; proteins can get more stability from ionic forces c. Though strong, disulfide bridges put a strain on the backbone d. Disulfide bridges can only occur just after praline in the amino acid sequence e. They make the protein rigid and many proteins must change shape as they work 8. Which of the following is NOT true of protein quaternary structure? a. A single polypeptide chain may have quaternary structure b. Hydrogen bonds may hold the polypeptides in contact c. Disulfide bridges may hold the polypeptides in contact d. A quaternary protein cannot have fewer than two carboxyl groups e. The same kinds of stabilizing forces are involved as in tertiary structure 9. Some of the strongest biological structures (e.g., beaks and claws) are made of many molecules of the protein keratin. What else is true of structures made of Keratin? a. Disulfide bridges bind the proteins together b. Each protein is a single long alpha helix c. Hair is another example d. Both (a) and (b) e. (a), (b) and (c) There are no Graphics for this exam ANSWERS Module 3 Lab Worksheet Carbohydrates: 1. e, 2. c, 3. c, 4. b, 5. e, 6. b, 7. d Lipids: 1. b, 2. e, 3. e, 4. a, 5. a, 6. b, 7. d, 8. c Protein: 1. e, 2. b, 3. c, 4. a, 5. e, 6. a, 7. e, 8. a, 9. e A few Hints: Carbs Question 1. The chemical compound that contains sugar and stores hereditary information is DNA, which we will study further in the next unit. Carbs Question 3. Admittedly, the wording on this question is a little off, but, what is the least "intrusive" change you can do to a sugar and still make another, different sugar? (Hint, in the Disaccharides exercise take a look at the 3rd carbon of glucose and compare it to galactose). Protein question 2. The "backbone" in a protein is the NH2-C-COOH part of EVERY amino acid that connects one amino acid to another - and they are all the same (only the side chains of the different amino acids vary). So, changing an amino acid in the primary structure of a protein wouldn't (repeat, would NOT) change the backbone.