Mastering Biology Chapter 5

All of the following contain amino acids except insulin. antibodies. hemoglobin. enzymes. cholesterol.

cholesterol.

Which of the following polymers contain nitrogen? cellulose glycogen starch chitin amylopectin

chitin

The structural level of a protein least affected by a disruption in hydrogen bonding is the tertiary level secondary level. All structural levels are equally affected. quaternary level. primary level.

primary level

How many molecules of water are needed to completely hydrolyze a polymer that is 11 monomers long? 12 11 10 9 8

10

(see Picture 11) Which of the following molecules could be joined together by a phosphodiester type of covalent bond? 11 and 12 6 and 15 3 and 8 11 and 13 3 and 4

11 and 12

Current best estimates suggest that life has been on Earth for how long? 3.5 thousand years 3.5 million years 3.5 billion years 3.5 trillion years

3.5 billion years

Which of the following pairs of base sequences could form a short stretch of a normal double helix of DNA? 5´-GCGC-3´ with 5´-TATA-3' 5´-purine-pyrimidine-purine-pyrimidine-3´ with 3´-purine-pyrimidine-purine-pyrimidine-5´ 5´-ATGC-3´ with 5´-GCAT-3´ All of these pairs are correct. 5´-AGCT-3´ with 5´-TCGA-3´

5´-ATGC-3´ with 5´-GCAT-3´

Which of the following statements about the formation of polypeptides from amino acids is true? A bond can form between any carbon and nitrogen atom in the two amino acids being joined. Polypeptides form by condensation or hydrolysis reactions. The reaction occurs through the addition of a water molecule to the amino acids. A bond forms between the carboxyl functional group of one amino acid and the amino functional group of the other amino acid.

A bond forms between the carboxyl functional group of one amino acid and the amino functional group of the other amino acid.

Which molecule is a nucleotide? ATP The amino acid glycine Deoxyribose

ATP

Select the statement that is incorrect. Complex sugars are carbohydrates. All carbohydrates have the general formula Cn(H2O)n. Simple sugars are carbohydrates. Simple sugars contain only carbon, oxygen, and hydrogen atoms.

All carbohydrates have the general formula Cn(H2O)n.

Which complex carbohydrate contains only a-1,4-glycosidic linkages? Amylopectin Cellulose Amylose Glycogen

Amylose

Which of the following is not attached to the central carbon atom in an amino acid? An amino functional group An oxygen A carboxyl functional group A side chain ("R group")

An oxygen

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? C18H10O15 C18H32O16 C3H6O3 C6H10O5 C18H36O18

C18H32O16

The molecular formula for glucose is C6H12O6. What would be the molecular formula for a polymer made by linking ten glucose molecules together by dehydration reactions? C60H102O51 C6H12O6 C60H120O60 C60H111O51 C60H100O50

C60H102O51

A simple sugar is composed of equal parts carbon and water, which gave rise to the general name of any sugar as a _______. Polysaccharide Carbohydrate Disaccharide monosaccharide

Carbohydrate

Which part of an amino acid is always acidic? Amino functional group Side chain ("R group") Carboxyl functional group None of the above

Carboxyl functional group

_____ is the most abundant organic compound on Earth. Lactose Glycogen Starch Cellulose Glucose

Cellulose

Which of the following complex carbohydrates is listed with its correct function? Amylose: main component of plant starch Chitin: constituent of bacterial cell walls Starch: primary energy-storage molecule in animals Cellulose: structural component of plant cell walls

Cellulose: structural component of plant cell walls

How will brief heating (to 95°C) affect macromolecular structures in aqueous solution? Proteins will hydrolyze into amino acids. DNA duplexes will unwind and separate. DNA duplexes will unwind and separate, and proteins will unfold (denature). Proteins will unfold (denature). Starch will hydrolyze into monomeric sugars.

DNA duplexes will unwind and separate, and proteins will unfold (denature).

The flow of genetic information in a cell goes from _____. DNA to lipid to protein protein to RNA to DNA DNA to RNA to glucose DNA to ribosomes to RNA DNA to RNA to protein

DNA to RNA to protein

Which of the following best summarizes the relationship between dehydration reactions and hydrolysis? Hydrolysis creates monomers, and dehydration reactions break down polymers. Dehydration reactions assemble polymers, and hydrolysis reactions break down polymers. Dehydration reactions ionize water molecules and add hydroxyl groups to polymers; hydrolysis reactions release hydroxyl groups from polymers. Dehydration reactions can occur only after hydrolysis. Dehydration reactions eliminate water from lipid membranes, and hydrolysis makes lipid membranes water permeable.

Dehydration reactions assemble polymers, and hydrolysis reactions break down polymers

Lactose the Sugar in milk is a ______, Because it can be split into two monosaccharides Polysaccharide Carbohydrate Disaccharide monosaccharide

Disaccharide

You discover a new means of energy transfer by organisms living in hydrothermal vents in the ocean. Who is most likely to be interested in funding your research? Chris McKay J.Craig Venter John Sutherland Everett Shock

Everett Shock

Which of the following is true of cellulose? It is a polymer composed of enantiomers of glucose. It is a polymer composed of enantiomers of glucose, it is a storage polysaccharide for energy in plant cells, it is digestible by bacteria in the human gut, and it is a major structural component of plant cell walls. It is a major structural component of plant cell walls. It is a storage polysaccharide for energy in plant cells. It is digestible by bacteria in the human gut.

It is a major structural component of plant cell walls

(see Picture 12) Which of the following statements is true regarding the molecule illustrated in the figure? Molecules of this type are usually liquid at room temperature. It is a saturated fatty acid and a diet rich in this molecule may contribute to atherosclerosis. It is a saturated fatty acid, a diet rich in this molecule may contribute to atherosclerosis, and molecules of this type are usually liquid at room temperature. It is a saturated fatty acid. A diet rich in this molecule may contribute to atherosclerosis.

It is a saturated fatty acid and a diet rich in this molecule may contribute to atherosclerosis.

Which of the following scientists is closest to creating life? John Sutherland Everett Shock J. Craig Venter Chris McKay

J. Craig Venter

Which molecule is not a carbohydrate? Lipid Glycogen Cellulose Starch

Lipid

Which of these is NOT a lipid? cholesterol phospholipid steroids wax RNA

RNA

If life exists or originated on another planet, most scientists today believe that it is which of the following planets? Mars Venus Neptune Saturn

Mars

Which of the following statements about monosaccharide structure is true? All monosaccharides contain carbon, hydrogen, oxygen, and nitrogen atoms. Monosaccharides can be classified according to the spatial arrangement of their atoms. Aldoses and ketoses differ in the position of their hydroxyl groups. A six-carbon sugar is called a pentose.

Monosaccharides can be classified according to the spatial arrangement of their atoms.

Which monomers make up RNA? Polymers Amino acids Nucleotides Simple sugars

Nucleotides

Which polysaccharide contains a modified monosaccharide? Peptidoglycan Cellulose Starch Glycogen

Peptidoglycan

A carbohydrate that yields many monosaccharides when hydrolyzed is a ______. Polysaccharide Carbohydrate Disaccharide monosaccharide

Polysaccharide

________ structure is the sequence of amino acids in a protein. Primary Secondary Tertiary Quaternary

Primary

(see Picture 1) There are four levels of protein structure. These figures show primary, secondary, tertiary, and quaternary protein structure. Which level(s) of protein structure may be stabilized by covalent bonds? None of the levels of protein structure is stabilized by covalent bonds. Secondary level of protein structure Primary, tertiary and quaternary levels of protein structure

Primary, tertiary and quaternary levels of protein structure

Which polymers are composed of amino acids? Monomers Carbohydrates Proteins Nucleic acids

Proteins

________ structure is the result of two or more protein subunits assembling to form a larger, biologically active protein complex. Primary Secondary Tertiary Quaternary

Quaternary

(see Picture 1) These figures show the four levels of protein structure: primary, secondary, tertiary, and quaternary structure. Which level of protein structure is characteristic of some, but not all, proteins? Secondary level of protein structure Quaternary level of protein structure Tertiary level of protein structure

Quaternary level of protein structure

Which of the following is true regarding current scientific thought? RNA and DNA are the same thing. DNA originated before RNA. RNA and DNA originated at the same time. RNA originated before DNA.

RNA originated before DNA

________ structure describes the alpha-helices and beta-sheets that are formed by hydrogen bonding between backbone atoms located near each other in the polypeptide chain. Primary Secondary Tertiary Quaternary

Secondary

What structural difference accounts for the functional differences between starch and cellulose? Starch and cellulose differ in the glycosidic linkages between their glucose monomers. Starch can be digested by animal enzymes, whereas cellulose cannot. Starch is a polymer of glucose, whereas cellulose is a polymer of fructose.

Starch and cellulose differ in the glycosidic linkages between their glucose monomers

________ structure is achieved when a protein folds into a compact, three dimensional shape stabilized by interactions between side-chain R groups of amino acids. Primary Secondary Tertiary Quaternary

Tertiary

The label on a container of margarine lists "hydrogenated vegetable oil" as the major ingredient. What is the result of adding hydrogens to vegetable oil? The hydrogenated vegetable oil has more "kinks" in the fatty acid chains. The hydrogenated vegetable oil is less likely to clog arteries. The hydrogenated vegetable oil has a lower melting point. The hydrogenated vegetable oil stays solid at room temperature. The hydrogenated vegetable oil has fewer trans fatty acids.

The hydrogenated vegetable oil stays solid at room temperature.

Which feature of large biological molecules explains their great diversity? The many classes of large biological molecules The diversity of elements found in large biological molecules The many ways that monomers of each class of biological molecule can be combined into polymers

The many ways that monomers of each class of biological molecule can be combined into polymers

(see Picture 3) The accompanying table represents the results of an experiment where the effects of pH buffers on an enzyme found in saliva (amylase) were studied. A spectrophotometer set at 500nm was used to measure absorbance at the various pH levels every 20 sec for 2 min. The higher absorbance values would indicate greater enzyme activity. All experiments were conducted at the same temperature. Which statement correctly identifies the result that the optimum pH for amylase function is 7? At pH 9, the enzyme is denatured and will lose its function, but not its structure. At pH 4, the structure of the enzyme will be altered, and the enzyme would not be able to catalyze the reaction. 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. 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.

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.

DNAase is an enzyme that catalyzes the hydrolysis of the covalent bonds that join nucleotides together. What would first happen to DNA molecules treated with DNAase? The phosphodiester bonds between deoxyribose sugars would be broken. The pyrimidines would be separated from the deoxyribose sugars. All bases would be separated from the deoxyribose sugars. The purines would be separated from the deoxyribose sugars. The two strands of the double helix would separate.

The phosphodiester bonds between deoxyribose sugars would be broken.

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? The pyrimidines would be separated from the deoxyribose sugars. All bases would be separated from the deoxyribose sugars. The phosphodiester linkages of the polynucleotide backbone would be broken. The purines would be separated from the deoxyribose sugars. The two strands of the double helix would separate.

The phosphodiester linkages of the polynucleotide backbone would be broken

(see Picture 2) High temperatures or various chemical treatments will denature a protein causing it to lose its shape and hence its ability to function. If a denatured protein remains dissolved it often renatures when its normal physical or chemical environment is restored as shown in the diagram below. Which statement best explains the connection between the sequence and subcomponents of a protein and its properties? A renatured protein will not function properly since proteins cannot regain their original sequence of amino acids after denaturation. The unique shape of a protein provides that protein with the ability to carry on several different functions. The specific shape of a protein is naturally known to the original sequence of amino acids so the protein will function properly after renaturation. A denatured protein will continue to have the same function since only the structure of the protein is affected.

The specific shape of a protein is naturally known to the original sequence of amino acids so the protein will function properly after renaturation.

Why are human sex hormones considered to be lipids? They are essential components of cell membranes. They are made of fatty acids. They are hydrophilic compounds. They are not soluble in water. They contribute to atherosclerosis.

They are not soluble in water.

Why are human sex hormones considered to be lipids? They are hydrophilic compounds. They are made of fatty acids. They are not soluble in water. They are essential components of cell membranes. They contribute to atherosclerosis

They are not soluble in water

Which of the following is true regarding saturated fatty acids? They are the predominant fatty acid in corn oil. They are usually produced by plants. They are usually liquid at room temperature. They are the principal molecules in lard and butter. They have double bonds between carbon atoms of the fatty acids.

They are the principal molecules in lard and butter

Which of the following statements concerning unsaturated fats is true? They generally solidify at room temperature. They have fewer fatty acid molecules per fat molecule. They are more common in animals than in plants. They contain more hydrogen than do saturated fats having the same number of carbon atoms. They have double bonds in the carbon chains of their fatty acids.

They have double bonds in the carbon chains of their fatty acids

Which of the following statements concerning unsaturated fats is true? They have fewer fatty acid molecules per fat molecule. They contain more hydrogen than do saturated fats having the same number of carbon atoms. They generally solidify at room temperature. They are more common in animals than in plants. They have double bonds in the carbon chains of their fatty acids.

They have double bonds in the carbon chains of their fatty acids.

Which of the following statements concerning saturated fats is not true? They have multiple double bonds in the carbon chains of their fatty acids. They are more common in animals than in plants. They contain more hydrogen than unsaturated fats having the same number of carbon atoms. They generally solidify at room temperature. They are one of several factors that contribute to atherosclerosis.

They have multiple double bonds in the carbon chains of their fatty acids.

True or false? Enzymes in the digestive tract catalyze hydrolysis reactions. True False

True

True or false? Peptidoglycan is a polysaccharide found only in bacteria. True False

True

Glycogen is _____. a transport protein that carries oxygen a polysaccharide found in animals a polysaccharide found in plant cell walls the form in which plants store sugars a source of saturated fat

a polysaccharide found in animals

Large organic molecules are usually assembled by polymerization of a few kinds of simple subunits. Which of the following is an exception to this statement? a contractile protein a steroid DNA cellulose an enzyme

a steroid

Which modifications of fatty acids will best keep triglycerides solid at warmer temperatures? creating trans double bonds to the fatty acids adding hydrogens and trans double bonds to the fatty acids adding hydrogens to the fatty acids creating cis double bonds to the fatty acids adding cis double bonds and trans double bonds to the fatty acids

adding hydrogens and trans double bonds to the fatty acids

Polysaccharides, triacylglycerides, and proteins are similar in that they are synthesized as a result of peptide bond formation between monomers. are synthesized from monomers by dehydration reactions. all contain nitrogen in their monomer building blocks. are synthesized from monomers by the process of hydrolysis. are decomposed into their monomers by dehydration reactions.

are synthesized from monomers by dehydration reactions.

A function of cholesterol that does not harm health is its role _____. the most abundant male sex hormone as the primary female sex hormone All of cholesterol's effects cause the body harm. in calcium and phosphate metabolism as a component of animal cell membranes

as a component of animal cell membranes

Lactose, a sugar in milk, is composed of one glucose molecule joined by a glycosidic linkage to one galactose molecule. How is lactose classified? as a monosaccharide as a hexose as a polysaccharide as a pentose as a disaccharide

as a disaccharide

Which of these is a phospholipid? Picture 6 Picture 7 Picture 8 Picture 9 Picture 10

bent and weird

Which of the following categories includes all others in the list? carbohydrate disaccharide monosaccharide starch polysaccharide

carbohydrate

A molecule with the chemical formula is probably a monosaccharide lipid. carbohydrate. carbohydrate and lipid only. carbohydrate and monosaccharide only

carbohydrate and monosaccharide only

Which of these classes of biological molecules consist of both monomers and polymers? nucleic acids lipids, carbohydrates, proteins, and nucleic acids all consist of only macromolecular polymers carbohydrates proteins lipids

carbohydrates

Which of these classes of biological molecules consist of both small molecules and macromolecular polymers? nucleic acids carbohydrates lipids, carbohydrates, proteins, and nucleic acids all consist of only macromolecular polymers lipids proteins

carbohydrates

Plant cell walls consist mainly of _____. chlorophyll peptidoglycan chitin cellulose None of the choices is correct.

cellulose

Which of these is a polysaccharide? glucose sucrose lactose galactose cellulose

cellulose

Palm oil and coconut oil are more like animal fats than are other plant oils. Because they _____ than other plant oils, they may contribute to cardiovascular disease. contain less hydrogen contain more double bonds contain more sodium are less soluble in water contain fewer double bonds

contain fewer double bonds

The difference between the sugar in DNA and the sugar in RNA is that the sugar in DNA contains one less oxygen atom. is an aldehyde sugar and the sugar in RNA is a keto sugar. is in the α configuration and the sugar in RNA is in the β configuration. is a six-carbon sugar and the sugar in RNA is a five-carbon sugar. can form a double-stranded molecule.

contains one less oxygen atom

A molecule with the formula C6H12O6 is probably a fatty acid. protein. nucleic acid. carbohydrate. hydrocarbon.

fatty acid

Which of these molecules is not formed by dehydration reactions? Which of these molecules is not formed by dehydration reactions? disaccharides protein DNA amylose fatty acids

fatty acids

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

glycogen, starch, and amylopectin

Sucrose is formed when glucose is joined to fructose by a(n) _____. ionic bond peptide linkage ester linkage phosphodiester linkage glycosidic linkage

glycosidic linkage

(see Picture 4) Which of the following descriptors is true of the molecule shown in the figure? hexose and fructose only hexose glucose hexose and glucose only fructose

hexose and glucose only

Humans can digest starch but not cellulose because the monomer of starch is glucose, while the monomer of cellulose is glucose with a nitrogen-containing group. humans harbor starch-digesting bacteria in the digestive tract. the monomer of starch is glucose, while the monomer of cellulose is galactose. humans have enzymes that can hydrolyze the α glycosidic linkages of starch but not the β glycosidic linkages of cellulose. humans have enzymes that can hydrolyze the β glycosidic linkages of starch but not the α glycosidic linkages of cellulose.

humans have enzymes that can hydrolyze the α glycosidic linkages of starch but not the β glycosidic linkages of cellulose.

Classify these amino acids as acidic, basic, neutral polar, or neutral nonpolar. (view 2)

k

Classify these amino acids as acidic, basic, neutral polar, or neutral nonpolar. (view 1)

k

All of the following are polysaccharides except cellulose. amylopectin. lactose. chitin. glycogen.

lactose.

All of the following are polysaccharides except cellulose. chitin. lactose. glycogen. amylopectin.

lactose.

glucose + glucose —> _____ by _____. starch + water ... dehydration synthesis cellulose + water ... hydrolysis sucrose + water ... dehydration synthesis maltose + water ... dehydration synthesis lactose + water ... hydrolysis

maltose + water ... dehydration synthesis

(see Picture 4) If two molecules of the general type shown in the figure were linked together, carbon-1 of one molecule to carbon-4 of the other, the single molecule that would result would be fructose. galactose. glucose. maltose. sucrose.

maltose.

Which of these is a source of lactose? sugar beets milk sugar cane starch potatoes

milk

A ______ cannot be hydrolyzed any further Polysaccharide Carbohydrate Disaccharide monosaccharide

monosaccharide

The characteristic that all lipids have in common is that _____. none of them dissolves in water they are all made of fatty acids and glycerol they all contain nitrogen they do not have a high energy content they are all acidic when mixed with water

none of them dissolves in water

The building blocks or monomers of nucleic acid molecules are called _____. polysaccharides nucleotides fatty acids pyrimidines and purines DNA and RNA

nucleotides

Which of these is rich in unsaturated fats? a fat that is solid at room temperature lard butter olive oil beef fat

olive oil

A hydrophobic amino acid R group (side group) would be found where in a protein? on the inside of the folded chain, away from water forming a peptide bond with the next amino acid in the polypeptide chain only at one end of a protein chain forming hydrogen bonds with other R groups on the outside of the folded chain, in the water

on the inside of the folded chain, away from water

The four main categories of large biological molecules present in living systems are _____. proteins, DNA, RNA, and steroids nucleic acids, carbohydrates, monosaccharides, and proteins monosaccharides, lipids, polysaccharides, and proteins proteins, nucleic acids, carbohydrates, and lipids RNA, DNA, proteins, and carbohydrates

proteins, nucleic acids, carbohydrates, and lipids

(see Picture 5) This figure is an example of a(n) _____. steroid saturated fat unsaturated fat protein nucleic acid

saturated fat

Some regions of a polypeptide may coil or fold back on themselves. This is called _____, and the coils or folds are held in place by _____. tertiary structure ... hydrogen bonds tertiary structure ... covalent bonds secondary structure ... peptide bonds primary structure ... covalent bonds secondary structure ... hydrogen bonds

secondary structure ... hydrogen bonds

The enzyme amylase can break glycosidic linkages between glucose monomers only if the monomers are the α form. Which of the following could amylase break down? starch, cellulose, and chitin starch starch and chitin only cellulose chitin

starch

(see Picture 13) What is the structure shown in the figure? fatty acid molecule phospholipid molecule steroid molecule oligosaccharide molecule pentose molecule

steroid molecule

Which of the following is an example of hydrolysis? the reaction of two monosaccharides, forming a disaccharide with the release of water the reaction of a fat, forming glycerol and fatty acids with the consumption of water the synthesis of a nucleotide from a phosphate, a pentose sugar, and a nitrogenous base with the production of a molecule of water the synthesis of two amino acids, forming a peptide with the release of water the reaction of a fat, forming glycerol and fatty acids with the release of water

the reaction of a fat, forming glycerol and fatty acids with the consumption of water

(see Picture 11) A fat (or triacylglycerol) would be formed as a result of a dehydration reaction between one molecule of 9 and three molecules of 10. one molecule of 5 and three molecules of 10. one molecule of 5 and three molecules of 9. three molecules of 5 and one molecule of 9. three molecules of 9 and one molecule of 10.

three molecules of 9 and one molecule of 10.

Dehydration reactions are used in forming which of the following compounds? proteins polysaccharides triacylglycerides, polysaccharides, and proteins triacylglycerides triacylglycerides and proteins only

triacylglycerides, polysaccharides, and proteins

(see Picture 14) The molecule shown in the figure is a(n) unsaturated fatty acid. triacylglycerol. polypeptide. polysaccharide. saturated fatty acid.

unsaturated fatty acid.

In animal metabolism, most of the monomers released by digestion of food macromolecules are metabolized to provide energy. Only a small portion of these monomers are used for synthesis of new macromolecules. The net result is that water is consumed by animal metabolism. water is generated during homeostasis, but water is consumed during periods of growth. water is consumed during homeostasis, but water is generated during periods of growth. water is generated by animal metabolism. the water consumed is exactly balanced by the water generated, to maintain homeostasis.

water is consumed by animal metabolism.

A dehydration reaction (or condensation reaction) is the process in which _____. water molecules are attracted to each other water molecules are used as a source of raw material to break down polymers to monomers water molecules are produced as a polymer is formed from monomers the bonds between the individual monomers of a polymer are broken by the addition of water molecules None of the choices is correct.

water molecules are produced as a polymer is formed from monomers