Question 1 Which of the following statements concerning fatty acids is CORRECT? Select one:

a. Most of them contain an even number of carbons.

b. They may have either a carboxylic, aldehyde, or hydroxyl at position one.

c. They all contain one or more double bonds.

d. They are a constituent of sterols.

e. They are strongly hydrophilic.

Question 2 Which of the following is TRUE of sphingolipids? Select one:

a. They do not contain glycerol.

b. Their fatty acid linkage is a carbon (organic) ester.

c. They always contain glycerol and fatty acids.

d. They may contain up to three fatty acids.

e. They may be charged, but are never amphipathic.

Question 3 Which of the following molecules or substances contain, or are derived from, fatty acids? Select one:

a. Beeswax

b. Prostaglandins

c. Sphingolipids

d. Triacylglycerols

e. All of the above contain or are derived from fatty acids.

Question 4 Which of the following is NOT true of all naturally occurring DNA? Select one:

a. Deoxyribose units are connected by 3',5'-phosphodiester bonds.

b. The amount of A always equals the amount of T.

c. The ratio A+G/T+C is constant for all natural DNAs.

d. The two complementary strands are antiparallel.

e. Two hydrogen bonds form between G and C.

Question 5 The 'energy carrier' ATP is an example of a(n): Select one:

a. deoxyribonucleoside triphosphate

b. di-nucleotide

c. ribonucleotide monophosphate

d. ribonucleoside triphosphate

e. all of the above

Question 6 In the DNA double helix (B form), the A-T and G-C base pairs share which one of the following properties? Select one: a. The distance between the bases is the same in both pairs, within a few tenths of an angstrom.

b. The molecular weights of the two base pairs are identical.

c. The number of hydrogen bonds formed between the bases is the same.

d. Each pair makes 50% of th ecomposition of any given coding sequence.

e. All of the above.

Question 7 Chargaff's rules state that in typical DNA: Select one:

a. A = G.

b. A = C.

c. A = U.

d. A + T = G + C.

e. A + G = T + C.

Question 8 What is TRUE about double bonds in fatty acids: Select one:

a. any organism produces both cis- ad trans- fatty acids

b. trans-fatty acids have a lower melting point

c. trans fatty acids can occur naturally

d. cis-fatty acids pack more densly in a biological membrane

e. All of the above.

Question 9 In standard fatty acid nomenclature, number 1 is assigned to: Select one:

a. The last carbon in the fatty acid tail

b. The carboxyl carbon

c. The carbon right after the carboxyl carbon

d. The first double bond carbon

e. None of the above

Question 10 The nucleotide base showing below connects to its ribose or deoxyribose via group _____ and makes legitimate watson-crick base-pairs using groups ______. Select one:

a. 3; 4,5,6

b. 3; 4,5

c. 6; 1,2,3

d. 6; 1,2

e. 1; 3,4,5

Question 11The fatty acid designated 18:2(? 9,12): Select one:

a. has two double bonds, one between carbos 8 and 9, one between carbons 11 and 12

b. has shortened by 2 carbons, with a double bond bridging th eoriginal carbons 9 and 12

c. is an omega-6 fatty acid

d. has 20 carbon atoms

e. All of the above.

Question 12 A DNA chain is being elongated by adding Select one:

a. deoxynucleosides to the free 5' end

b. deoxynucleosides to the free 3' end

c. deoxynucleotides to the free 5' end

d. deoxynucleotides to the free 3' end

Question 13 Which of the following is NOT true of sterols? Select one:

a. Cholesterol is a sterol that is commonly found in mammals.

b. They are commonly found in bacterial membranes.

c. They are more common in plasma membranes than in intracellular membranes (mitochondria, lysosomes, etc.).

d. They are precursors of steroid hormones.

e. They have a structure that includes four fused rings.

Question 14 The double helix of DNA in the B-form is stabilized by: Select one:

a. covalent bonds between the 3' end of one strand and the 5' end of the other.

b. hydrogen bonding between the phosphate groups of two side-by-side strands.

c. hydrogen bonds between the riboses of each strand.

d. nonspecific base-stacking interaction between two adjacent bases in the same strand.

e. ribose interactions with the planar base pairs.

Question 15 Which of the following is true for a fatty acid with the name 20:5 (?5, 8, 11, 14, 17) Eicosapentaenoic acid? Select one: a. It contains 25 carbons

b. It is considered fully saturated

c. It is considered an omega-3 fatty acid

d. It is a monosaturated fatty acid

Question 16 Which of the following deoxyoligonucleotides will hybridize with a DNA containing the sequence (5')AGACTGGTC(3')? Select one:

a. (5')CTCATTGAG(3')

b. (5')GAGTCAACT(3')

c. (5')GACCAGTCT(3')

d. (5')TCTGACCAG(3')

e. (5')TCTGGATCT(3')

Question 17 In the Watson-Crick model of DNA structure (now called B-form DNA.: Select one:

a. a purine in one strand always hydrogen bonds with a purine in the other strand.

b. A-T pairs share three hydrogen bonds.

c. G-C pairs share two hydrogen bonds.

d. the 5' ends of both strands are at one end of the helix.

e. the bases occupy the interior of the helix.

Question 18 Industrial process hydrogenation has which of the following effects? Select one:

a. Converts many cis double bonds to trans double bonds

b. Converts many single bonds to cis-double bonds

c. Increases the melting temperature of vegetable oil

d. Converts vegetable oil from a solid to a liquid at room temperature

e. A and C are correct

f. B and D are correct

Question 19 Biological waxes are all: Select one:

a. esters of glycerol and a long-chain alcohol.

b. esters of single fatty acids with long-chain alcohols.

c. esters of glycerol and three long-chain saturated fatty acids.

d. sphingolipids.

e. none of the above.

Question 20 Match the type of bond with the role below: A __________ links base to ribose in a nucleotide; A ________ joins adjacent nucleotides in one strand; A___________ joins complementary nucleotides in two strands; (a) phosphodiester bond (b) N-glycosidic bond (c) hydrogen bond Select one:

a. a;b;c

b. c;b;a

c. b;c;a

d. c;a;b

e. b;a;c

Question 21 The nucleotide base showing below is _______ , and Watson-crick base paring for this base specifically involve the groups numbered ________ . Select one:

a. Adenine; 1,2

b. Guanine; 1,2,3

c. Adenine; 5,6

d. Guanine; 4,5,6

e. None of the above

Question 22 Which of the following is a legitimate precursor for DNA synthesis? Select one:

a. Nucleoside-triphosphate

b. Deoxynucleoside-triphosphate

c. Nucleoside-monophosphate

d. Deoxynucleoside-monophosphate

Question 23 Which of the following is CORRECT? Select one:

a. Phospholipase A cleaves the ester between the phosphate and the head group.

b. Phospholipase D cleaves any of the esters between glycerol and the fatty acids.

c. Phospholipase C cleaves the ester between glycerol and the phosphate group.

d. All of the above

Question 24 In the double-stranded configuration of DNA structure: Select one:

a. both strands run in the same direction, 3' - 5'; they are parallel.

b. phosphate groups project toward the middle of the helix, where they are protected from interaction with water.

c. T can form three hydrogen bonds with either G or C in the opposite strand.

d. the distance between the sugar backbone of the two strands is just large enough to accommodate either two purines or two pyrimidines.

e. the distance between two adjacent bases in one strand is about 3.4 Angstrom.