PORTAGE LEARNING CHEM 210 - MODULE 4 EXAM.

PORTAGE LEARNING CHEM 210 - MODULE 4 EXAM. Which of the following monosaccharides is a ketose? Dihydroxyacetone Galactose Glucose Glyceraldehyde Idose Dihydroxyacetone When two carbohydrates are epimers: One is a pyranose, the other a furanose One is an aldose, the other a ketose They differ in length by one carbon They differ only in the configuration about one carbon atom They react differently with iodine THEY DIFFER ONLY IN THE CONFIGURATION ABOUT ONE CARBON ATOM Which pair is anomeric? A) D-glucose and D-fructose B) D-glucose and L-fructose C) D-glucose and L-glucose D) -D-glucose and -D-glucose E) α-D-glucose and β-L-glucose D) -D-glucose and -D-glucose Question 1 3 / 3 pts Question 2 3 / 3 pts Question 4 3 / 3 pts Lactose is made from linking galactose and glucose. When this happens, . Gas is eliminated An anomeric carbon is formed on carbon-1 Water is released An epimer is formed An aldose is formed WATER IS RELEASED Amylose and amylopectin are both polymers of: A) α-D-glucose B) β-D-glucose C) Galactose D) Idose E) Maltose A) α-D-glucose Question 5 3 / 3 pts Question 6 3 / 3 pts Which statement about starch and glycogen is false? A) Both have β-D-glucose monomers B) Both starch and glycogen are energy storage polysaccharides C) Both are homopolymers of glucose D) Glycogen is more extensively branched than starch E) Both have O-glycosidic linkages A) Both have β-D-glucose monomers Which monosaccharide is not a six-carbon monosaccharide? Fructose Ribose Mannose Galactose Glucose RIBOSE The two monosaccharides shown below could best be described as: Question 7 3 / 3 pts Question 8 3/ 3 pts Anomers Aldoses Ketoses Epimers Pentoses EPIMERS Which arrow correctly identifies the atom that will become the anomeric carbon? Question 9 3 / 3 pts A Based on the form of the cyclic sugar below in a Haworth projection, which Fischer projection formula could have formed this structure? Question 10 0 / 3 pts B The following monosaccharides are covalently bonded. What type of bond unites them? A) α1 → 4 Question 11 3 / 3 pts B) α1 →β4 C) 1, 4 D) α1 → 6 E) β1 → 6 D) α1 → 6 Which statement about cellulose is true? Cellulose is the primary storage polysaccharide of animal cells Cellulose is a highly branched polysaccharide Cellulose is a homopolysaccharide The glucose residues of cellulose contain the same configuration as the glucose residues of amylose Cellulose is an anomer of chitin CELLULOSE IS A HOMOPOLYSACCHARIDE The polysaccharide cellulose is most chemically similar to: Glycogen Dextrose Glycogen Chitin Starch Question 12 0 / 3 pts Question 13 3 / 3 pts CHITIN Which of the following is the most common monosaccharide on earth? Ribose Cellulose Chitin Sucrose Glucose GLUCOSE The “D” in the D-carbohydrates stands for: Derivation Double Disaccharide 3-dimensional Dextrorotatory DEXTROROTATORY Which compound does not fit the formal definition of a carbohydrate? A. C6H12O6 Question 14 3 / 3 pts Question 15 3 / 3 pts Question 16 3 / 3 pts B. C7H10O7 C. C8H16O8 D. C3H6O3 E. C4H8O4 B. C7H10O7 Which letter represents the hemiacetal bond? Question 17 3 / 3 pts A B C D E C What is the configuration of the following compound? A) α B) β C) D Question 18 3 / 3 pts D) L E) Both A and C D Table sugar is also known as: Sucrose Dextrose Glucose Galactose Glycogen SUCROSE Amylopectin has α1 → 6 branching about every residues. 1 to 10 8 to 12 10 to 30 24 to 30 No branching 24 TO 30 What element besides C, H, and O is found in the chitin? Br N P Question 19 3 / 3 pts Question 20 3 / 3 pts Question 21 3 / 3 pts S Cl N Some carbohydrates form a(n) structure, which resembles a structure in proteins. A) α form B) β-turn C) βeta-sheet D) D-configuration E) α-helix E) α-helix The equilibrium between structures is called mutarotation. A) Anomer and epimer B) α and β Question 22 3 / 3 pts Question 23 3 / 3 pts Question 26 5 / 5 pts C) L and D D) Helix and beta sheet E) None of the above B) α and β Consider the functions of carbohydrates. Which of the following is not a function of these molecules? Structure Energy storage Enzyme structure Both A and B Both A and C ENZYME STRUCTURE The word saccharide means . Sugar Carbohydrate Energy molecule Sucrose Starch SUGAR Question 24 3 / 3 pts Question 25 3 / 3 pts (Short response) Table sugar dissolves easily in water. Given its structure, explain why this is. Sucrose contains -OH groups which can form hydrogen bonds with water. These non-covalent interactions permit solubility by permitting carbohydrates to interact with water and become an aqueous solution. Question 27 5 / 5 pts (Short response) In the following structure: A) In the above structure, how many monosaccharide units are furanoses and how many are pyranoses? B) What is the linkage between the monosaccharides? C) Is this a reducing sugar? A) 2 pyranoses; 0 furanoses B) β1 → 4 C) yes, it has free anomeric carbon Question 28 5 / 5 pts (Short response) A hiker is lost in the wilderness and without food. He runs across several beetles with hard chitin exoskeletons. Would he get nutrition in the form of glucose from eating these beetles? Explain. The human enzyme cannot break down the bond between the glucose residues in chitin. The bond is a β1 →4, but human enzymes only act upon α 1 →4. So, no he should not eat the beetles as food. Question 29 5/ 5 pts (Short response) What is the difference between amylose and amylopectin? Amylose is a single chain of glucose molecules connected by alpha 1 → → 4 linkages. This molecule contains a single main chain. Amylopectin also contains a main chain of glucose residues connected by alpha 1 → → 4 linkages, but it has branches every 24 to 30 glucose residues. The branches are alpha 1 → → 6 linkages, which have branch chains that are also connected by alpha 1 → → 4 linkages. Question 30 5 / 5 pts (Short response) A) Which carbon in the following molecule determines if the molecule is D or L? Indicate the letter corresponding the correct carbon (“A”, “B”, etc.) and explain. B) Is this molecule D or L? Carbon E. It is the penultimate carbon and tells the viewer if the sugar is D or L. This monosaccharide is D.