Biology Test Ch 4/5

which of the following combinations of molecules illustrated could be linked to form a nucleotide? A) 11, 12, and 13 B) 5, 9, and 10 C) 1, 2, and 11 D) 3, 7, and 8

A) 11, 12, and 13

Which of the following best summarizes the relationship between dehydration reactions and hydrolysis? A) Dehydration reactions and hydrolysis reactions assemble polymers from monomers B) Dehydration reactions and hydrolysis reactions assemble polymers from monomers C) Hydrolysis reactions create polymers, and dehydration reactions create monomers D) Dehydration reactions illuminate water from membranes; hydrolysis reactions add water to membranes

A) Dehydration reactions and hydrolysis reactions assemble polymers from monomers

In sickle cell disease, as a result of a single amino acid change, the mutant hemoglobin tetramers associate with each other and assembles into large fibers. Based on this information alone, we can conclude that sickle cell hemoglobin exhibits _____ A) Altered primary structure and altered quarternary Structure; the secondary and tertiary structure is may or may not be altered B) Only altered primary structure C) only altered tertiary structure D) only altered quarternary structure

A) Altered primary structure and altered quarternary Structure; the secondary and tertiary structure is may or may not be altered

The molecule shown in the figure is a A) Steroid B) phospholipid C) fatty acid D) triaglycerol

A) Steroid

Choose the term that correctly describes the relationship between these two sugar molecules: A) Structural isomers B) Enantiomers C) Cis-trans isomers D)Isotopes

A) Structural isomers

Which statement correctly identifies the result that the optimum pH for amylase function is 7? A) The pH with the highest absorbance values would indicate the optimum pH for amylase since this pH does not affect the structure or function of the protein B) The pH with the lowest absorbance values would indicate the optimum pH for amylase since this pH does not affect the structure or function of the protein C) At pH 4, the structure of the enzyme will be altered, and the enzyme would not be able to catalyze the reaction D) At pH 9, the enzyme is denatured and will lose its function, but not its structure

A) The pH with the highest absorbance values would indicate the optimum pH for amylase since this pH does not affect the structure or function of the protein

A tripeptide has _________ A) Three amino acids and two peptide bonds B) Three amino acids and three peptide bonds C) Two amino acids and three peptide bonds D)Four amino acids and three peptide bonds

A) Three amino acids and two peptide bonds

Which of the following descriptions best fits the class of molecules known as nucleotides A) a nitrogenous base, a phosphate group, and a sugar B) a nitrogenous base and a phosphate group C) a nitrogenous base and a sugar D)a sugar and a purine or pyramidine

A) a nitrogenous base, a phosphate group, and a sugar

A molecule with the chemical formula is C6H12O6 probably a________ A) monosaccharide B) polysaccharide C) fatty acid D) nucleic acid

A) monosaccharide

The structural level of a protein is least affected by a disruption in hydrogen bonding is the A) primary level B) secondary level C) tertiary level D)quarternary level

A) primary level

How do phospholipids interact with water molecules? A) The polar heads interact with water; the nonpolar tails do not B) Phospholipids do not interact with water because water is polar and lipids are nonpolar. C) Phospholipids dissolve in water D) The polar heads avoid water; the nonpolar tails attract water (because water is polar and opposites attract)

A) the polar heads interact with water; the non polar tails do not

How many molecules of water are released during the polymerization of a 20 monomer-long cellulose molecule? A) 10 B) 19 C) 20 D)40

B) 19

In carbohydrates, the ratio of hydrogen (H) to oxygen (O) is________ A) 1:1 B) 2:1 C) 3:1 D) 4:1

B) 2:1

If one strand of DNA molecule has the sequence of bases 5'-ATTGCA-3', the mRNA synthesized following the template will be _____ A) 5'-UGCAAU-3' B) 3'-UAAGCU-5' C) 5'-TCGAAT-3' D)5'-TAACGT-3'

B) 3'-UAAGCU-5'

Which the following pairs of base sequences could form a short stretch of a normal double helix of DNA? A) 5'-AGCT-3 with 5'-TCGA-3 B) 5'-ATGC-3' with 5'-GCAT-3' C) 5'-GCGC-3' with 5'-TATA-3' D) All of these pairs are correct

B) 5'-ATGC-3' with 5'-GCAT-3'

Which parts of the amino acid X and Y are involved in the formation of a peptide bond? A) Carboxyl group of X an amino group of Y B) Amino group of X and carboxyl group of Y C) Side chains of both X and Y D)Carboxyl group of X and the side chain of Y

B) Amino group of X and carboxyl group of Y

Visualize the structural formula of each of the following hydrocarbons. Which hydrocarbon has a double bond in it's carbon skeleton? A) C2H2 B) C2H4 C) C2H6 D) C3H8

B) C2H4

What term does insoluble fiber referred to on food packages? A) Amylopectin B) Cellulose C) Starch D) Polypeptides

B) Cellulose

Which polysaccharide is an important component in the structure of many animals and fungi? A) Cellulose B) Chitin C) Amylopectin D) Amylose

B) Chitin

The central role of molecular biology states that________ A) RNA is transcribed into proteins B) DNA is transcribed into RNA which is transcribed into protein C) DNA is translated into RNA which is transcribed into proteins D)DNA is translated into proteins

B) DNA is transcribed into RNA which is transcribed into protein

Which of the following statements are true for lipids? A) Lipids are true polymers and mix poorly with water B) Lipids mix poorly with water C) Waxes and pigments are not lipids D) Lipids are true polymers

B) Lipids mix poorly with water

Which of the following is true of unsaturated fats? A) They contain more hydrogens than saturated fats having the same number of carbon atoms B) They have double bonds in their fatty acid chains C) They are more common in animals than plants D) They generally solidify at room temperature

B) They have double bonds in their fatty acid chains

For lipids to be fluid at room temperature, they should have ______? A) single bonds only B) a higher number of cis double bonds C) a longer carbon chain D) a higher number of glycerol molecules

B) a higher number of cis double bonds

The glycosidic linkage is analogous to which of the following proteins A) an amino group B) a peptide bond C) a disulfide bonds D) a B pleated sheet

B) a peptide bond

Which chemical group is most likely to be responsible for an organic molecule behaving as a base? A) phosphate B) amino C) carbonyl D) hydroxyl

B) amino

Saturated fats______ A) Are generally liquid at room temperature B) contain more hydrogen than unsaturated fats that consist of the same number of carbon atoms C) are more common in plants than animals D) have multiple double bond in the carbon chains of their fatty acids

B) contain more hydrogen than unsaturated fats that consist of the same number of carbon atoms

A New organism is discovered in the forests of Costa Rica. Scientists there determined that the polypeptide sequence of hemoglobin from the new organism has 72 amino acid differences from humans, 65 differences from a gibbon, 49 differences from a rat, and five differences from a frog. These data suggest that the new organism is more closely related to A) humans than to frogs B) frogs than to humans C) gibbons than to rats D)rats than to frogs

B) frogs than to humans

The relation between amino acid and polypeptide is similar to the relation between _____ A) Glycogen and glucose B) nucleotide and nucleic acid C) phospholipid and plasma membrane D) triglycerides and steroids

B) nucleotide and nucleic acid

Which functional group is not present in this molecule? A) amino B) sulfhydryl C) hydroxyl D)carboxyl

B) sulfhydryl

People who are lactose intolerant cannot extract energy from milk because ________ A) lactose is too big to be digested by enzymes B) they are missing the enzyme C) milk is fermented to a by-product, which cannot be digested D) they are missing the bacteria that can digest lactose

B) they are missing the enzyme

The molecular formula for glucose is C6H12O6. What would be the molecular formula for a polymer made by linking 10 glucose molecules together by dehydration reactions A) C60H120O60 B) C60H100O50 C) C60H102O50 D) C60H111O51

C) C60H102O50

Humans can digest starch but not cellulose because _______ A) Starch is softer than cellulose B) The monomer of starch is glucose, while the monomer of cellulose is galactose C) Humans have enzymes that can hydrolyze the a-glycosidic linkages of starch but not the b-glycosidic linkages of cellulose D) Starch monomers are joined by covalent bonds, and the cellulose monomers are joined by ionic bonds

C) Humans have enzymes that can hydrolyze the a-glycosidic linkages of starch but not the b-glycosidic linkages of cellulose

In an RNA sample ________ A) The number of purine always equals the number of pyramidine B) The number of thiamine may or may not equal the number of adenine C) The number of purine may or may not equal the number of and pyramidine D) The number of thiamine always equals the number of uracil

C) The number of purine may or may not equal the number of and pyramidine

Enzymes that break down DNA catalyze the hydrolysis of the covalent bonds that join nucleotides together. What would happen to DNA molecules treated with these enzymes? A) The pyridines would be separated from the deoxyribose sugars B) The two strands of the double helix would separate C) The phosphodiester linkages of the polynucleotide backbone would be broken D) All the bases would be separated from the deoxyribose sugars

C) The phosphodiester linkages of the polynucleotide backbone would be broken

Starch and Cellulose_______ A) are structural components of the plant cell wall B) are cis and trans isomers of each other C) are polymers of glucose D) are used for energy storage in plants and animals

C) are polymers of glucose

One of the primary functions of RNA molecules is to_____ A) Act as a pattern or blueprint for DNA B) Transmit genetic information to offspring C) function in the synthesis of proteins D) make a copy of itself does ensuring genetic continuity

C) function in the synthesis of proteins

Which of the following is not a polymer? A) starch B) RNA C) glucose D) DNA

C) glucose

Phospholipids and triglycerides both _________ A) have a phosphate B) have three fatty acid C) have a glycerol backbones D) contains serine or some other organic compound

C) have a glycerol backbones

The label on a container of margarine lists 'hydrogenated vegetable oil" as the major ingredient. Hydrogenated vegetable oil __________ A) is less likely to clog arteries B) has more "kinks" in the fatty acid chains C) is solid at room temperature D) has fewer trans fatty acids

C) is solid at room temperature

What makes lipids/fats hydrophobic? A) the glycerol moiety B) the carboxyl group at one end of the molecule C) presence of relatively normal C-H bonds D)their long carbon skeleton

C) presence of relatively normal C-H bonds

The chemical reaction illustrated ________ A) is a hydrolysis reaction B) links two polymers to form a monomer C) results in a polypeptide D) joins two fatty acids together

C) results in a polypeptide

Which of the following provides the information necessary to stipulate a proteins 3-D shape? A) Number of water molecules in the vicinity B) peptide bonds between different amino acid C) sequence of amino acids in the polypeptide chain D) side chains of various amino acids

C) sequence of amino acids in the polypeptide chain

Organic chemistry is currently defined as A) The study of natural (as opposed to synthetic) compounds B) The study of compounds made only by living cells C) the study of carbon compounds D) the study of hydrocarbons

C) the study of carbon compounds

Which of the following is a major difference between RNA and DNA? A) type of phosphate B) type of glycosidic bond C) type of sugar D) type of purines

C) type of sugar

Which of the following Molecules act as building blocks (monomers) of polypeptides A) 1, 4, and 6 B) 7, 8, and 13 C) 11, 12, and 13 D) 2, 7, and 8

D) 2, 7, and 8

Which molecule is a saturated fatty acid/ A) 8 B) 5 C) 1 D) 9

D) 9

The molecular formula for glucose is C6H12O6. What would be the molecular formula for a molecule made by linking three glucose molecules together by dehydration reactions? A) C18H36O18 B) C18H30O15 C) C6H10O5 D) C18H32O16

D) C18H32O16

A fat (or triaglycerol) would be formed as a result of a dehydration reaction between A) Three molecules of 9 and one molecule of 10 B) One molecule 5 and three molecules of 10 C) One molecule of 5 and three molecules of nine D) One molecule of 9 and three molecules of 10

D) One molecule of 9 and three molecules of 10

If 14C- labeled uracil is added to the growth medium of cells, what macromolecules will be labeled __________ A) Polypeptides B) DNA C) Both DNA and RNA D) RNA

D) RNA

When nucleotides polymerize to form a nucleic acid, ____________ A) hydrogen bonds form between the bases of two nucleotides B) covalent bonds form between the bases of two nucleotides C) a hydrogen bond forms between the sugar of one nucleotide and the phosphate of the second D) a covalent bond forms between the sugar of one nucleotide and the phosphate group of a second

D) a covalent bond forms between the sugar of one nucleotide and the phosphate group of a second

which the following categories include all others in the list? A) starch B) disaccharide C) polysaccharide D) carbohydrate

D) carbohydrate

You would like to loose weight. Which of the following should be your preferred food group? A) sucrose and starch B) Lactose and glucose C) starch and fructose D) cellulose and fructose

D) cellulose and fructose

Cooking oil and gasoline (a hydrocarbon) are not amphipathic molecules because they _______ A) Have hydrophobic and hydrophilic regions B) are highly reduced molecules C) do not have a non-polar region D) do not have a polar or charged regions

D) do not have a polar or charged regions

The enzyme amylase can break glycosidic linkages between glucose monomers only if the monomers are in the form. Which of the following could amylase break down? A) starch, chitin, and cellulose B) cellulose and chitin C) glycogen, and cellulose D) glycogen, starch, and amylopectin

D) glycogen, starch, and amylopectin

What component of amino acid structure varies among different amino acids? A) The long carbon hydrogen tails of the molecule B) the presence of a central C atom C) the glycerol molecule that forms the backbone of the amino acid D) the components of the R group

D) the components of the R group

Which action could produce a carbonyl group? A) The Addition of a hydroxyl to a phosphate B) The addition of a thiol to a hydroxyl C) The replacement of the nitrogen of an amine with oxygen D)The replacement of the -OH of a carboxyl group with the hydrogen

D)The replacement of the -OH of a carboxyl group with the hydrogen