Chem 30B Third Exam

The neurotransmitter ________ plays an important role in addiction, and affects brain processes that control movement, emotions, and pleasure.

dopamine

Morphine and heroin bind to the same receptors as ________ and act as painkillers and sedatives.

enkephalins

The 10 amino acids that the human body cannot synthesize are known as the ________.

essential amino

2-ethyl-1-heptanamine is an alternative name for N-ethyl-1-heptanamine.

false

2-ethylheptanamide is an alternative name for Nethylheptanamide.

false

A hemiacetal is a compound that contains a hydroxyl group (-OH) and an alkoxy group (- OR) on adjacent carbon atoms

false

All amino acids have at least one chirality center.

false

All carbonyl compounds that contain a nitrogen atom are amides.

false

Amino acids typically exist in nature as neutral molecules with all uncharged atoms.

false

An individual can survive on a completely fatfree diet.

false

D-Amino acids have the -NH3 + group on the left side in the Fischer projection.

false

Fats contain a larger percentage of unsaturation in their structures than oils do.

false

Fentanyl (structure shown) is a drug used for anesthesia and analgesia. There are two 2- phenylethylamine units in fentanyl.

false

High-density lipoproteins (HDLs) transport cholesterol from where it is synthesized, to the tissues.

false

In hydrolysis of a peptide or protein, the addition of water breaks the hydrogen bonds that hold the amino acids together in the peptide chain

false

In order for cholesterol to be transported from where it is synthesized in the liver to the tissues, it combines with phospholipids and proteins to form small water-soluble spherical particles called lipozymes.

false

In the polypeptide, Gly-Ser-Val-Ala, the amino acid at the N-terminal end of the peptide chain is Ala.

false

Insulin is a small protein consisting of two polypeptide chains held together by hydrogen bonds.

false

Lipids are defined as biomolecules that contain fatty acids as part of their structure.

false

Only ammonium salts with less than six carbon atoms are water soluble

false

Primary and secondary amines have higher boiling points than alcohols of similar molecular size.

false

Soap is prepared by the acid hydrolysis (saponification) of a triacylglycerol.

false

Strychnine (structure shown) is a very toxic alkaloid used as a pesticide. There are two amine groups in strychnine

false

Tertiary (3°) amides have higher boiling points and melting points than primary (1°) and secondary (2°) amides.

false

The carbonyl group of an aldose is reduced to a secondary alcohol using hydrogen (H2) in the presence of palladium (Pd) metal.

false

The conversion of an amine to an ammonium salt is an irreversible process

false

The lock-and-key model is often used to explain why some enzymes catalyze a wide variety of substrate reactions.

false

The molecule below is an omega-9 fatty acid.

false

The naturally occurring enantiomer of a monosaccharide is distinguished by the prefix L-

false

The peptide leucyl phenylalanylvalylvaline is abbreviated as Leu-Phen-Ala-Val-Val.

false

The reactant in an enzyme-catalyzed reaction is called a cofactor.

false

The structure shown below is an example of a trans fatty acid

false

The α-helix and the β-pleated sheet are examples of the tertiary structure of a protein

false

The β anomer of a cyclic monosaccharide has the -OH group drawn down, below the ring

false

There are twenty-one (21) tetrahedral carbons in Vitamin D4 (structure shown).

false

Too little dopamine causes schizophrenia

false

Triacylglycerols form lipid bilayers.

false

By convention, the C-terminal amino acid is always written at the right end of the peptide chain and the N-terminal amino acid at the left.

true

Caffeine and nicotine are alkaloids

true

Carbohydrates that are oxidized with Benedict's reagent are called reducing sugars, because they reduce the Cu2+ in Benedict's reagent to Cu+ during the reaction.

true

Common names are generally used for simple amines.

true

Cyclohexylammonium fluoride is soluble in water

true

Derivatives of 2-phenylethylamine contain a benzene ring bonded to a two-carbon chain that is bonded to a nitrogen atom

true

Derivatives of 2-phenylethylamine may be used to treat asthma

true

Dextromethorphan (structure shown) is a cough suppressant found in many over-the-counter cold and cough medicines. Dextromethorphan is a derivative of 2-phenylethylamine.

true

Dopamine affects brain processes that control movement, emotions, and pleasure.

true

Eicosanoids are a group of biologically active compounds containing 20 carbon atoms derived from the fatty acid arachidonic acid.

true

Except for glycine, all amino acids have a chirality center on the α carbon.

true

Globular proteins are coiled into compact shapes with hydrophilic outer surfaces that make them water-soluble.

true

HIV protease inhibitors are used to treat HIV by binding to an enzyme needed by the virus to replicate itself

true

Heptylamine is the common name for 1- heptanamine.

true

Hydrogen bonding is possible between the side chains of the amino acids tyrosine and threonine

true

Hydrolases can catalyze hydrolysis reactions by using water to break chemical bonds.

true

In Fischer projections, the horizontal bonds represent groups projecting forward (on wedges) and the vertical bonds represent groups projecting backwards (on dashes).

true

When soap is mixed with water, the nonpolar hydrocarbon tails dissolve the dirt on the exterior of micelles.

false

When trimethylamine is heated up with propanoic acid, an amide is formed.

false

The configuration of the chirality center ________ (closest to/farthest from) the carbonyl group determines whether a monosaccharide is D or L

farthest from

Triacylglycerols, or triglycerides, are triesters formed from glycerol and three ________ molecules.

fatty acid

________ proteins are composed of long linear polypeptide chains that are bundled together to form rods or sheets that are insoluble in water and serve structural roles

fibrous

Lipids come in a wide variety of structures and have many different functions.

true

Lysases can catalyze the removal of water and CO2

true

Many amines with useful medicinal properties are sold as their ammonium salts

true

Many low molecular weight amines have very foul odors.

true

Monosaccharides create hydrogen bonds with water due to the presence of numerous hydroxyl groups making them very water soluble

true

Naturally occurring fatty acids have an even number of carbons.

true

Nearly all carbohydrates contain chirality centers

true

Neurotransmitters are stored in small packets called vesicles in the filaments of the axon near the synapse.

true

Nicotine, a highly toxic amine, is responsible for the addictive nature of smoking

true

No one plant source has sufficient amounts of all of the essential amino acids.

true

Primary (1°) and secondary (2°) amines have higher boiling points and melting points than tertiary (3°) amines of comparable size.

true

Prostaglandins are a group of carboxylic acids that contain a five-membered ring, and are responsible for inflammation.

true

SSRIs are antidepressants that effectively increase the concentration of serotonin

true

Saturated fatty acids have no double bonds in their long hydrocarbon chains

true

Serine exists primarily in its neutral form at a pH ~ 6.

true

Some lipids and proteins on the cell membrane surface are bonded to carbohydrates, forming glycolipids and glycoproteins.

true

Tertiary amines do not contain N-H bonds, unlike primary and secondary amines. Thus, tertiary amines have lower boiling points than that similarly sized primary and secondary amines.

true

The amide bonds in peptides and proteins are called peptide bonds.

true

The coating that surrounds and insulates nerve cells, the myelin sheath, is particularly rich in sphingomyelins, and is vital for proper nerve function.

true

The hydrolysis of the amide bonds in a protein forms the individual amino acids that comprise the primary structure

true

The postsynaptic neuron contains the receptors that bind the neurotransmitter.

true

The prefix N- is used in front of the names of the groups bonded directly to the nitrogen when naming amides.

true

The three-dimensional structure of a trans triacylglycerol shows its similarity to saturated triacylglycerols.

true

The β-pleated sheet forms when two or more peptide chains, called strands, line up side-byside with the C=O and N-H bonds in the plane of the sheets.

true

There are six (6) trigonal planar carbons in Vitamin D4 (structure shown).

true

To be classified as an unsaturated fatty acid, the molecules must contain one or more double bonds

true

Trans double bonds can be formed when triacylglycerols are partially hydrogenated.

true

Unsaturated fatty acids are sometimes classified as omega- n acids, where n is the carbon at which the first double bond occurs in the carbon chain, beginning at the end of the chain that contains the CH3 group

true

Vitamins are organic compounds required in small quantities for normal metabolism.

true

When a monosaccharide forms a cyclic hemiacetal, the carbon atom that is part of the hemiacetal is a new chirality center, called the anomeric carbon.

true

When an amine dissolves in water, the hydroxide ion concentration of the solution increases.

true

α-Keratin in hair is a fibrous protein composed almost exclusively of α-helix units that wind together to form a superhelix.

true

Alkaloids are naturally occurring amines derived from plant sources.

true

All aldoses and ketoses are reducing sugars.

true

All neurotransmitters contain nitrogen atoms

true

Amino acids with an additional COOH group in the side chain are classified as acidic amino acids

true

Both albuterol and salmeterol are derivatives of 2-phenylethylamine.

true

To form an amide from a carboxylic acid, a substitution occurs where the ________ of the carboxylic acid is replaced by a nitrogencontaining group.

-OH group

How many of the lipids listed below contain an amide bond? --waxes --triacylglycerols --sphingomyelins --steroids --phosphoacylglycerols A) 0 B) 1 C) 2 D) 3 E) 4

C) 2

There are ________ amino acids that occur naturally in proteins. A) 12 B) 15 C) 20 D) 21 E) 30

C) 20

How many fatty acids are required to form a triacylglycerol? A) 1 B) 2 C) 3 D) 4 E) 5

C) 3

What is the three-letter abbreviation of asparagine? A) Asp B) Asg C) Asn D) Arg E) Apr

C) Asn

What wax is formed from palmitic acid [CH3(CH2)14COOH] and the alcohol CH3(CH2)21OH? A) CH3(CH2)21COO(CH2)14CH3 B) CH3(CH2)14COO(CH2)14CH3 C) CH3(CH2)14COO(CH2)21CH3 D) CH3(CH2)21COO(CH2)21CH3 E) CH3(CH2)14COOCH2(CH2)21CH3

C) CH3(CH2)14COO(CH2)21CH3

Trypsin is a digestive enzyme that hydrolyzes peptide bonds only when the carbonyl group in the amide bond comes from Lys or Arg. What fragments result when the peptide Gly-Lys-ArgAla-Ala-Arg is hydrolyzed by trypsin? A) Gly, Lys, Arg, Ala-Ala, Arg B) Gly-Lys, Arg-Ala-Ala, Arg C) Gly-Lys, Arg, Ala-Ala-Arg

C) Gly-Lys, Arg, Ala-Ala-Arg

Which statement concerning carbohydrates is incorrect? A) Carbohydrates serve important energy and structural roles for both plants and animals. B) Monosaccharides are the simplest carbohydrates and are known as simple sugars. C) Humans store excess glucose for short term energy requirements in the polysaccharide cellulose. D) Carbohydrates that can be oxidized by Benedict's reagent are called reducing sugars.

C) Humans store excess glucose for short term energy requirements in the polysaccharide cellulose.

Which is an example of a cofactor? A) lactose B) lactose dehydrogenase C) NAD+ (nicotinamide adenine dinucleotide) D) tryptophan E) pyruvate

C) NAD+ (nicotinamide adenine dinucleotide)

Denaturation of a protein results in the loss of its native conformation and its biological activity. Which statement best describes what happens to a protein when it is denatured? A) Peptide bonds are broken. B) New amino acids are joined to the peptide backbone. C) Secondary, tertiary, and quaternary levels of structure are disrupted. D) The N-terminal and C-terminal ends of the protein are hydrolyzed by enzymes.

C) Secondary, tertiary, and quaternary levels of structure are disrupted.

Lidocaine is an amine used as a local anesthetic and cardiac depressant. When Lidocaine is administered, it is administered as its amine salt. Why is the amine salt, rather than the free amine, used? A) The amine salt is more basic than the free amine. B) The amine salt is a gas at room temperature and can be rapidly inhaled. C) The amine salt has a higher solubility in water and bodily fluids than the free amine. D) The amine salt is not as addictive as the free amine. E) The amine salt is less likely to degrade on the pharmacy shelf than the amine.

C) The amine salt has a higher solubility in water and bodily fluids than the free amine.

Which of the following would be tetrabutylammonium chloride? A) [CH3(CH2)3]4NH2+ Cl B) [CH3(CH2)3]4NH+ Cl C) [CH3(CH2)3]4N+ Cl D) [CH3(CH2)3]4NH3+ Cl E) [CH3(CH2)3]4N Cl

C) [CH3(CH2)3]4N+ Cl

Waxes are formed from the reaction between which two types of compounds? A) a fatty acid and an amide B) a high molecular weight alcohol and an ester C) a fatty acid and a high molecular weight alcohol D) an ester and a fatty acid E) a fatty acid and a water molecule

C) a fatty acid and a high molecular weight alcohol

Which is a hydrolyzable lipid? A) a leukotriene B) cholesterol C) a phosphoacylglycerol D) vitamin A E) None of the are hydrolyzable lipids

C) a phosphoacylglycerol

Which is a nonhydrolyzable lipid? A) a triacylglycerol B) a wax C) an eicosanoid D) a phospholipid E) None of the examples are nonhydrolyzable lipids.

C) an eicosanoid

Which of the following is a polysaccharide? A) glucose B) lactose C) cellulose D) sucrose E) fructose

C) cellulose

Which polysaccharide has β-glycosidic bonds? A) glycogen B) amylose C) cellulose D) amylopectin E) starch

C) cellulose

What is the process of altering the shape of a protein without breaking the amide bonds that form the primary structure? A) hydrolysis B) competitive inhibition C) denaturation D) oxidation E) reduction

C) denaturation

What is the strongest type of interaction between two cysteine amino acid side chains in a protein? A) hydrogen bonding B) london dispersion forces C) disulfide bond D) electrostatic interactions E) amide bond

C) disulfide bond

The structure of lipids is ________. A) dominated by ionic regions B) dominated by hydrophilic regions C) dominated by hydrophobic regions D) equally dominated by hydrophilic and hydrophobic regions E) dominated by the polar functional group

C) dominated by hydrophobic regions

What functional group is contained in most hydrolyzable lipids? A) amide B) ether C) ester D) carboxylic acid E) alkene

C) ester

Which is an example of a globular protein? A) collagen B) α-keratin C) hemoglobin D) amylopectin

C) hemoglobin

Which protein carries O2 in the bloodstream? A) keratin B) ferritin C) hemoglobin D) myoglobin E) glutamine

C) hemoglobin

When drawing dipeptides, the ________ group is drawn on the left and the ________ group on the right.

-NH3+, -COO-

Which is not an example of a lipid? A) phenol B) triacylglycerol C) cholesterol D) vitamin E E) steroids

A) phenol

There are ________ chirality centers in Vitamin A (structure shown)

0

The majority of the monosaccharides found in nature and in the human body are ________. A) classified as "D" B) classified as "L" C) cyclic monosaccharides D) starches E) chitin chains

A) classified as "D"

A tertiary amide contains ________ C—N bonds.

3

Lobeline (structure shown) is a natural alkaloid found in a number of plants including "Indian tobacco" (Lobelia inflata) and "Devil's tobacco" (Lobelia tupa). Lobeline has been used as a smoking cessation aid. How many chirality centers are in lobeline?

3

Polysaccharides have ________ or more monosaccharides joined together.

3

Fexofenadine is a non-sedating antihistamine with a single amine functional group. Classify the amine in fexofenadine.

3 degree

There are ________ chirality centers in prednisone (structure shown)

6

Lovastatin was the first statin drug to be marketed and used for lowering blood cholesterol. How many chirality centers are present in lovastatin?

8

When converting a Fischer projection to a Haworth projection, where are all of the substituents on the right side of the carbon skeleton drawn in the Haworth projection? A) down B) up C) down in an α anomer and up in a β anomer D) down in an β anomer and up in a α anomer

A) down

What type of intermolecular forces exist between the side chains of glutamic acid and lysine? A) electrostatic attraction B) London dispersion forces C) hydrogen bond D) disulfide bond

A) electrostatic attraction

Hydrolysis of triacylglycerols in the body occurs with the aid of which reagent? A) enzymes B) bases C) oxidizing agents D) sulfuric acid E) esters

A) enzymes

What is the charge on an amino acid at a pH below its pI? A) positive B) neutral C) negative D) The charge or lack of charge varies depending on the amino acid.

A) positive

What process is used to move large polar molecules and ions, such as Cl- and HCO3 - , through a cell membrane, traveling from the side of higher concentration to the side of lower concentration? A) facilitated transport B) simple diffusion C) active transport D) effusion E) channel transport

A) facilitated transport

What monosaccharide is found in cellulose, starch, and glycogen? A) glucose B) galactose C) sucrose D) fructose E) maltose

A) glucose

Which conditions are commonly diagnosed by measuring the levels of specific enzymes in the blood? A) heart attack B) high blood pressure C) pregnancy D) migraines E) asthma

A) heart attack

Which amino acids contain sulfur? A) asparagine, glutamine, proline B) cysteine, methionine C) serine, glutamine D) triptophan, tyrosine, phenylalanine E) leucine, isoleucine, valine

B) cysteine, methionine

Norepinephrine is an important neurotransmitter. Classify the amine in norepinephrine. A) 1 o B) 2 o C) 3 o D) 4 o E) This amine is impossible to classify

A) 1 o

Which statement is not true? A) A cofactor is always a metal ion needed for an enzyme-catalyzed reaction to occur. B) The names of most enzymes end in the suffix - ase. C) An enzyme-catalyzed reaction can be 106 to 1012 times faster than a similar uncatalyzed reaction. D) Enzymes are proteins that serve as biological catalysts for reactions in all living organisms. E) Enzymes contains an active site to bind the substrate.

A) A cofactor is always a metal ion needed for an enzyme-catalyzed reaction to occur.

Which is a hydrolyzable lipid? A) A triacylglycerol B) A steroid C) An eicosanoid D) A fat -soluble vitamin E) None of the examples are hydrolyzable lipids.

A) A triacylglycerol

Which compound has the highest melting point? A) CH3(CH2)14COOH B) CH3(CH2)10CH=CH(CH2)2COOH C) CH3(CH2)2CH=CH(CH2)4CH=CH(CH2)4COOH D) CH3(CH2)2CH=CH(CH2)2CH=CH(CH2) 2CH=CH(CH2)2COOH E) CH3(CH2)2CH=CHCH2CH=CH(CH2)2C H=CH(CH2)2CH=CH(CH2)2COOH

A) CH3(CH2)14COOH

Which amine has the highest boiling point? A) CH3(CH2)5CH2NH2 B) CH3CH2CH2N(CH2CH2CH2CH3)2 C) CH3CH2CH2CH2CH2NHCH2CH3 D) CH3(CH2)3CH2NH2 E) All of the amines are expected to have a similar boiling point.

A) CH3(CH2)5CH2NH2

Amino acids are the building blocks of the body's proteins. Which statement concerning amino acids is false? A) There are approximately 20 standard amino acids that occur naturally in the proteins of the human body. B) Except for when R=H, amino acids are chiral molecules. C) The amino acids found in human proteins are "alpha" amino acids. D) The properties of amino acids and the proteins they compose are determined by the nature of the side chain groups that are present. E) The NH3 + group of one amino acid and the COO− group of another amino acid react to form the amide bond.

A) There are approximately 20 standard amino acids that occur naturally in the proteins of the human body.

What type of inhibitor binds to the enzyme but does not bind at the active site? A) a noncompetitive inhibitor B) a competitive inhibitor C) a reversible inhibitor D) an irreversible inhibitor E) an isomerase inhibiter

A) a noncompetitive inhibitor

Which of the following describes a reversible, noncompetitive inhibiter? A) binds to an enzyme temporarily limiting its activity but does not bind at the active site B) binds to an enzyme temporarily limiting its activity and competes with the substrate for binding to the active site C) binds to an enzyme permanently destroying its activity but does not bind at the active site D) binds to an enzyme permanently destroying its activity and competes with the substrate for binding to the active site

A) binds to an enzyme temporarily limiting its activity but does not bind at the active site

What is the particular sequence of amino acids of a protein that are joined together by peptide bonds called? A) the primary structure of a protein B) the secondary structure of a protein C) the tertiary structure of a protein D) the quaternary structure of a protein

A) the primary structure of a protein

What product is formed when tripropylamine is treated with acetic acid? A) tripropylammonium acetate B) acetamide C) tripropylammonia acetate D) tripropylamide E) None of the products listed are correct.

A) tripropylammonium acetate

________ bonds between cysteine residues are the only covalent bonds that stabilize the tertiary structure of a protein.

disulfide

Prostaglandins and leukotrienes are two types of ________. A) low-density lipoproteins B) eicosanoids C) fat-soluble vitamins D) adrenal cortical steroids E) anabolic steroids

B) eicosanoids

Which amino acid is a basic amino acid? A) serine B) arginine C) cysteine D) alanine E) threonine

B) arginine

When an aldose is oxidized, the aldehyde functional group (-CHO) is converted into a ________ group. A) -C=O B) -COOH C) -OH D) -H E) -O

B) -COOH

How many different dipeptides can be formed when one valine reacts with one glycine? A) 1 B) 2 C) 3 D) 4 E) 5

B) 2

How many chirality centers are in leu-enkephalin (structure shown)? A) 2 B) 3 C) 4 D) 5 E) 9

B) 3

The term protein is usually reserved for polymers of more than ________ amino acids. A) 10 B) 40 C) 100 D) 200 E) 1000

B) 40

The formation of what color in the Benedict's test indicates a reducing sugar is present in solution? A) blue B) brick red C) bright yellow D) silver E) bright pink

B) brick red

How many different tripeptides can be formed when one isoleucine, one alanine, and one glycine react? A) 3 B) 6 C) 10 D) 18 E) 27

B) 6

What hydrolysis products are formed when the wax CH3(CH2)18COO(CH2)17CH3 is treated with aqueous sulfuric acid? _ A) CH3(CH2)18CHO + CH3(CH2)16CH2OH B) CH3(CH2)18COOH + CH3(CH2)16CH2OH C) CH3(CH2)18COOH + CH3(CH2)16CH3 D) CH3(CH2)18COOH + CH3(CH2)16COOH E) CH3(CH2)18CH2OH + CH3(CH2)16COOH

B) CH3(CH2)18COOH + CH3(CH2)16CH2OH

Which compound has the highest boiling point? A) (CH3)2CHCH2CH2CH2NH2 B) CH3CH2CH2CH2CH2COOH C) (CH3)2CHCH2CH2CH2OH D) CH3(CH2)6CH3 E) CH3(CH2)4CH3

B) CH3CH2CH2CH2CH2COOH

Why are humans not able to digest cellulose? A) Humans cannot digest glucose. B) Humans do not possess the enzyme necessary to hydrolyze the 1→4-βglycoside linkages found in cellulose. C) Humans do not possess the enzyme necessary to unwind the helical shape of the cellulose molecule. D) Humans do not possess the enzyme necessary to hydrolyze the 1→4-αglycoside linkages found in cellulose. E) Humans do not possess the enzyme, lactase, to cleave the 1→4-β-glycoside linkages found in cellulose

B) Humans do not possess the enzyme necessary to hydrolyze the 1→4-βglycoside linkages found in cellulose.

The contents on a box of cupcakes lists partially hydrogenated soybean oil. Partial hydrogenation of soybean oil has what effect? A) It produces fatty acid salts. B) It decreases the percent of unsaturation that is present. C) It hydrolyzes the triacylglycerol. D) It increases the number of fatty acids present. E) It decrease the number of hydrogen atoms present on the molecule.

B) It decreases the percent of unsaturation that is present.

What type of intermolecular forces exist between the side chains of isoleucine and valine? A) electrostatic attraction B) London dispersion forces C) hydrogen bond D) disulfide bond

B) London dispersion forces

What is the charge on a zwitterion? A) Positive B) Neutral C) Negative D) The charge or lack of charge varies depending on the amino acid.

B) Neutral

Which is not true about prostaglandins? A) Prostaglandins decrease gastric secretions. B) Prostaglandins decrease inflammation. C) Prostaglandins inhibit blood platelet aggregation. D) Prostaglandins stimulate uterine contractions. E) Prostaglandins relax the smooth muscles of the uterus.

B) Prostaglandins decrease inflammation.

What is the one-letter abbreviation of arginine? A) A B) R C) P D) G E) D

B) R

How is a dipeptide formed? A) The -NH3 + group of one amino acid forms an amide bond with the -NH3 + group of another amino acid and the elements of H2 are removed. B) The -NH3 + group of one amino acid forms an amide bond with the carboxylate (-COO- ) of another amino acid, and the elements of H2O are removed. C) The carboxylate (-COO- ) group of one amino acid forms an amide bond with the carboxylate (-COO- ) of another amino acid, and the elements of O2 are removed. D) The carboxylate (-COO- ) group of one amino acid forms an amide bond the - NH3 + group of another amino acid, and the elements of H2 are removed. E) The carboxylate (-COO- ) group of one amino acid forms an amide bond the - NH3 + group of another amino acid, and the elements of O2 are removed.

B) The -NH3 + group of one amino acid forms an amide bond with the carboxylate (-COO- ) of another amino acid, and the elements of H2O are removed.

The block diagram for a phosphoacylglycerol (glycerophospholipid) is shown below. Phosphoacylglycerols can interact with both water and other lipids, and therefore are well suited for their role in the lipid bilayer of cell membranes. Which statement best explains this behavior? A) They contain a phosphodiester. B) They contain both a hydrophobic region as well as a hydrophilic region. C) They contain both saturated fatty acids as well as unsaturated fatty acids. D) They contain both single bonds as well as double bonds. E) They contain esters rather than hydroxyl groups

B) They contain both a hydrophobic region as well as a hydrophilic region.

Which structural feature is not found in sphingomyelins? A) an amide bond B) a glycerol backbone C) a phosphodiester D) an alcohol E) a single fatty acid

B) a glycerol backbone

Heating a carboxylic acid with a primary amine forms water along with what organic product? A) a primary amide B) a secondary amide C) a tertiary amide D) an ester E) a secondary amine

B) a secondary amide

5-Hydroxytryptamine, commonly known as Serotonin, is drawn below. Serotonin is an antidepressant often called the happy chemical because it helps modulate mood. Which of the following correctly describes the types of functional groups present in serotonin? A) amide, ether, alkene B) alcohol, amine, aromatic C) alkene, ketone, amide D) amine, alkene, ester E) alcohol, amine, carboxylic acid

B) alcohol, amine, aromatic

What are monosaccharides with a carbonyl group at C1 called? A) anomers B) aldoses C) ketoses D) alditols E) stereoisomers

B) aldoses

What organic product is formed when a carboxylic acid reacts with an alcohol in the presence of sulfuric acid? A) an ether B) an ester C) a ketone D) an amide E) an amine

B) an ester

Disaccharides and polysaccharides contain monosaccharide units joined together by which of the following? A) hydrogen bonding B) glycosidic linkages C) hemiacetal bonds D) dipole-dipole forces

B) glycosidic linkages

What is a zymogen? A) an amino acid with a neutral charge B) inactive precursor of an enzyme C) a molecule that causes an enzyme to lose activity D) a nonprotein organic molecule needed for an enzyme-catalyzed reaction to occur E) the charged form of an amino acid

B) inactive precursor of an enzyme

What is the strongest type of interaction between the side chains of an isoleucine amino acid and a phenylalanine amino acid in a protein? A) hydrogen bonding B) london dispersion forces C) disulfide bond D) electrostatic interactions E) amide bond

B) london dispersion forces

What is the main component of the cell membrane? A) triacylglycerols B) phospholipids C) steroids D) waxes E) prostaglandins

B) phospholipids

Coniine, shown below, is an alkaloid extracted from poison hemlock. How is this nitrogen containing compound most appropriately classified? A) heterocyclic, primary amine B) secondary amine C) primary, heterocyclic amide D) lactam E) quaternary ammonium salt

B) secondary amine

What is responsible for the different blood types in humans? A) three or four proteins attached to a membrane monosaccharide on the surface of red blood cells B) three or four monosaccharides attached to a membrane protein on the surface of red blood cells C) three or four amino acids attached to a membrane monosaccharide on the surface of red blood cells D) three or four lipids attached to a membrane polysaccharide on the surface of red blood cells

B) three or four monosaccharides attached to a membrane protein on the surface of red blood cells

Based on its name, which compound is an enzyme? A) glucose B) triosephosphate isomerase C) N-acetyl-D-glucosamine D) dihydrofolate E) serine

B) triosephosphate isomerase

Which is not a fat-soluble vitamin? A) vitamin A B) vitamin C C) vitamin E D) vitamin K E) vitamin D

B) vitamin C

Clavulanic acid is a drug used in conjunction with some antibiotics to overcome certain types of antibiotic resistance. How many chirality centers are in the molecule of clavulanic acid shown below? A) 0 B) 1 C) 2 D) 3 E) 4

C) 2

When naming peptides, the _________- terminal amino acid is the one listed last and its - ine or - ic acid ending is changed to the suffix - yl.

C

Which amine has the lowest boiling point? A) (CH3)2CHNHCH2CH2CH2CH3 B) CH3CH2CH2CH2CH2CH2CH2NH2 C) (CH3)2NCH2CH2CH2CH2CH3 D) (CH3)2NCH2CH2CH2CH2CH2CH3 E) All of the compounds have the same boiling point.

C (CH3)2NCH2CH2CH2CH2CH3

Which compound has the highest boiling point? A) (CH3)2CHCH2COOCH3 B) CH3CH2CH2CH2CH2CH2CH2NH2 C) (CH3)2CHCH2CH2CH2CH2OH D) CH3(CH2)6CH3 E) All of the compounds have the same boiling point.

C) (CH3)2CHCH2CH2CH2CH2OH

Atorvastatin (structure shown) is the active ingredient in Lipitor, a drug classified as a statin, used for lowering blood cholesterol. Which of these functional groups is not present in atorvastatin? A) carboxylic acid B) benzene C) ketone D) amine E) amide

C) ketone

What is the C-terminal amino acid in the tetrapeptide glycylalanyisoleucylmethionine? A) alanine B) glycine C) methionine D) isoleucine

C) methionine

What is the name of the class of compounds with the general formula of R4N+ X- ? A) tertiary ammonium salts B) tetraammonium salts C) quaternary ammonium salts D) tertiary ammonia salts E) primary ammonium salts

C) quaternary ammonium salts

Which of these groups of compounds are phospholipids? A) leukotrienes B) fatty acids C) sphingomyelins D) adrenal cortical steroids E) None of these are phospholipids

C) sphingomyelins

Benzphetamine, shown below, is a habit-forming diet pill. How is this nitrogen-containing compound most appropriately classified? A) primary B) secondary C) tertiary D) quaternary E) quaternary ammonium salt

C) tertiary

What is the 3-dimensional shape of a peptide chain called? A) the primary structure of a protein B) the secondary structure of a protein C) the tertiary structure of a protein D) the quaternary structure of a protein

C) the tertiary structure of a protein

Which is not a function of a protein? A) provide support and structure B) regulate metabolism C) transport substances through the blood D) control muscle movements E) regulate blood glucose levels

C) transport substances through the blood

Which is not a neurotransmitter? A) serotonin B) norepinephrine C) tryptophan D) dopamine E) acetylcholine

C) tryptophan

Which compound has the lowest melting point? A) CH3(CH2)18COOH B) CH3(CH2)5CH=CH(CH2)7COOH C) CH3(CH2)7CH=CH(CH2)7COOH D) CH3(CH2)4CH=CH(CH2)4CH=CH(CH2)2CH =CH(CH2)2COOH E) CH3(CH2)4CH=CH(CH2)2CH=CH(CH2)2COOH

D) CH3(CH2)4CH=CH(CH2)4CH=CH(CH2)2CH =CH(CH2)2COOH

Complete metabolism of a triacylglycerol yields which of the following? A) glycerol, fatty acids, and a great deal of energy B) fatty acids and a great deal of energy C) fatty acids, H2O, and a great deal of energy D) CO2, H2O, and a great deal of energy E) glycerol, H2O, and a great deal of energy

D) CO2, H2O, and a great deal of energy

Fats and oils are structurally both triacylglycerols, but fats are solids at room temperature and oils are liquids at room temperature. Which statement best describes the reason for their difference in physical state? A) Fats are simple triacylglycerols and oils are mixed triacylglycerols. B) Oils are simple triacylglycerols and fats are mixed triacylglycerols. C) Oils contain longer fatty acid chains than fats do, and therefore have higher melting points than fats. D) Fats contain a higher percentage of saturated fatty acids than oils do, and therefore have higher melting points than oils.

D) Fats contain a higher percentage of saturated fatty acids than oils do, and therefore have higher melting points than oils.

Which compound is the most soluble in water? A) trihexylamine B) N-ethyl-1-heptanamine C) dibutylamine D) N-ethyl-1-pentanammonium bromide E) N-methyl- N-propylamine

D) N-ethyl-1-pentanammonium bromide

Which is a possible correct name for an amine? A) N,N-dipropylmethylamine B) 1,3-diethylaniline C) N,N,N-tributylaniline D) N-ethylpyrrolidine E) N-ethylpyridine

D) N-ethylpyrrolidine

At a pH value of 2, the amino and carboxyl groups in an amino acid will exist as A) NH3 + and COO− . B) NH3 + and COOH. C) NH2 and COOH. D) NH2 + and COO− . E) NH2 and COO−

D) NH2 + and COO−

Which statement concerning lipid functions is incorrect? A) Steroid hormones act as messenger molecules and regulate biochemical processes. B) Phospholipids, glycolipids, and cholesterol provide structure for cell membranes. C) Triacylglycerols are used for long term energy storage. D) Plants and animals use waxes for insulation. E) Sphingomyelins are a component of the myelin sheaths around nerve cells protecting nerve transmission.

D) Plants and animals use waxes for insulation.

What is the common structural feature found in carboxylic acids, amides, and esters? A) a carboxyl group B) a hydroxyl group C) an amino group D) a carbonyl group E) The three types of organic molecules share no common structural features.

D) a carbonyl group

Arecoline is used in veterinary medicine to treat parasitic worms. Which of the following correctly describes the types of functional groups present in Arecoline? A) amide, ether, alkene B) ester, amine, aromatic C) alkene, ketone, amide D) amine, alkene, ester E) ketone, amine, ether

D) amine, alkene, ester

Which of the following describes an irreversible, competitive inhibiter? A) binds to an enzyme temporarily limiting its activity but does not bind at the active site B) binds to an enzyme temporarily limiting its activity and competes with the substrate for binding to the active site C) binds to an enzyme permanently destroying its activity but does not bind at the active site D) binds to an enzyme permanently destroying its activity and competes with the substrate for binding to the active site

D) binds to an enzyme permanently destroying its activity and competes with the substrate for binding to the active site

Which choice is the only amino acid capable of forming a disulfide bond? A) methionine B) serine C) arginine D) cysteine

D) cysteine

To determine whether a monosaccharide is D or L, the configuration of the chiral center ________ must be determined. A) nearest to the carbonyl group B) in the center of the molecule C) nearest to the second -OH functional group D) farthest from the carbonyl group E) nearest to the third -OH functional group

D) farthest from the carbonyl group

Which is the simplest amino acid? A) serine B) glutamine C) cysteine D) glycine E) alanine

D) glycine

What is the polysaccharide form in which glucose is stored in animals? A) cellulose B) amylose C) amylopectin D) glycogen E) glycosaminoglycans

D) glycogen

About one half of the 223 amino acid residues in the enzyme trypsin are hydrophobic. Where in the tertiary structure of this globular protein are these residues most likely to be found? A) at the N-terminal end of the peptide chain B) at the C-terminal end of the peptide chain C) on the exterior surface of the folded protein D) in the interior of the folded protein

D) in the interior of the folded protein

The Lysergic Acid Diethyamide hallucinogen commonly referred to as LSD is drawn below. Which of these functional groups is not present in LSD? A) amine B) benzene C) amide D) ketone E) carbonyl

D) ketone

The protein in an uncooked egg is denatured during the process of cooking. The only level of the protein structure that is not modified is the A) primary structure. B) secondary structure. C) tertiary structure. D) quaternary structure. E) all structural levels are modified during the denaturation process.

D) quaternary structure.

What is the common type of reaction that all acyl group-containing compounds undergo? A) acid-base reactions B) saponification C) oxidation reactions D) substitution reactions E) addition reactions

D) substitution reactions

Which amino acids contain an aromatic ring? A) asparagine, glutamine, proline B) cysteine, methionine C) serine, glutamine D) triptophan, tyrosine, phenylalanine E) leucine, isoleucine, valine

D) tryptophan, tyrosine, phenylalanine

Which of the following can denature a protein? A) acid B) base C) heat D) agitation E) All of these can denature a protein

E) All of these can denature a protein

Which statement is not true? _ A) Cholesterol is the most prominent member of the steroid family. B) Cholesterol is insoluble in the aqueous medium of the blood. C) Cholesterol serves as the starting material for the synthesis of all other steroids. D) Cholesterol is a vital component for healthy cell membranes. E) Cholesterol cannot be synthesized in the body, and therefore is required in the diet.

E) Cholesterol cannot be synthesized in the body, and therefore is required in the diet.

In what way may drugs be used to affect neurotransmitters? A) A drug may prevent the binding of a neurotransmitter to a receptor. B) A drug may increase the amount of neurotransmitter released. C) A drug may prevent the release of a neurotransmitter. D) A drug may affect the degradation of a neurotransmitter. E) Drugs may affect neurotransmitters using all of the mechanisms listed.

E) Drugs may affect neurotransmitters using all of the mechanisms listed.

________ catalyze the conversion of one isomer into another

Isomerases

Primary and secondary amines can make intermolecular hydrogen bonds, but tertiary amines cannot, because tertiary amines do not contain a ________ bond.

N-H

Aldosterone regulates blood pressure and volume by controlling the concentration of Na+ and K+ in body fluids.

true

Amines act as proton ________ in water and acid.

acceptors

Amines are bases and are proton ________.

acceptors

A water-insoluble amine can be converted to a water-soluble ammonium salt by treatment with a/an ________.

acid

Amines react with ________ to form watersoluble salts

acids

The ________ of an enzyme is the region where substrate binding and catalysis occur.

active site

Carboxylic acids, esters, and amides are called ________ compounds

acyl

Triacylglycerols are stored in ________ cells below the skin and concentrated in some regions of the body.

adipose

A dipeptide contains two amino acids joined together by one ________ bond.

amide

An -NH2 group is known as an ________ group.

amino

In an acid-base reaction of an amine, the amine nitrogen always forms a new bond to a proton forming a/an ________ ion.

ammonium

The male sex hormones are called ________ and the two types of female sex hormones are ________ and ________.

androgens, estrogens and progestins

A benzene ring with an -NH2 group attached is referred to most often by its common name which is ________.

aniline

Aromatic amines with a nitrogen bonded directly to a benzene ring are named as derivatives of ________.

aniline

All aldoses will turn a ________ color when treated with Benedict's reagent.

brick red

Both esters and amides undergo hydrolysis to form ________.

carboxylic acid

Humans do consume insoluble fiber which is known to be rich in ________, a polysaccharide that humans cannot metabolize.

cellulose

The ________ is the aqueous medium inside the cell, separated from water outside the cell by the cell membrane.

cytoplasm

As the number of double bonds in a fatty acid increases, the melting point ________.

decreases

An ________ forms when the hemiacetal of one monosaccharide reacts with a -OH group of another monosaccharide creating an acetal.

disaccharide

The hydrolysis of a disaccharide cleaves the ________ linkage and forms two monosaccharides.

glycosidic

The C-O bond that holds together the rings of a disaccharide is called a ________.

glycosidic linkage

When a nitrogen is part of a ring, it is referred to as a ________.

heterocycle

Monosaccharides are polar compounds with ________ melting points.

high

________ are the chemical messengers of the endocrine system.

hormones

A ________ lipid can be converted into smaller molecules by aqueous hydrolysis.

hydrolyzable

The polar part of a fatty acid is said to be ________, or "water loving"

hydrophilic

The nonpolar part of a fatty acid is said to be ________, or "water fearing".

hydrophobic

Molecules that cause an enzyme to lose its activity are called ________.

inhibitors

Disulfide bonds stabilize the tertiary structure of proteins. When the disulfide bond is between the two -SH groups on the same chain, it can be classified as an ________ disulfide bond, and when the two -SH groups are on different chains, it can be classified as an ________ disulfide bond.

intramolecular, intermolecular

The pH at which an amino acid exists primarily in its neutral form is called its ________ point

isoelectric

Simvastatin, also sold as Zocor (structure shown), is a drug used to reduce the level of cholesterol in the bloodstream. Which of the following functional groups is not present in simvastatin?

ketone

A cyclic amide is called a(n) ________.

lactam

Individuals who are lactose intolerant no longer produce the enzyme ________

lactase

When the pH is ________ the pI, the overall charge on an amino acid will be positive. (greater than, less than, equal to)

less than

Cell membranes are made up of a structure called a(n) ________.

lipid bilayer

________ are the simplest carbohydrates.

monosaccharides

A/An ________ is a chemical messenger that transmits nerve impulses from one nerve cell (neuron) to another cell.

neurotransmitter

Amides are carbonyl compounds that contain a ________ atom bonded to the carbonyl carbon

nitrogen

A ________ lipid can not be cleaved into smaller units by aqueous hydrolysis

nonhydrolyzable

Estradiol and estrone are two estrogen hormones synthesized in the ________.

ovaries

Two common types of phospholipids are ________ and ________.

phosphoglycerides, and sphingomyelins

It is the exact sequence of amino acids, called its ________ structure, that determines the properties and functions of a protein.

primary

The neurotransmitter ________ plays an important role in mood, sleep, perception, and temperature regulation. Improper levels of this neurotransmitter in the brain have been linked to migraine headaches.

serotin

Lipids are biomolecules that are ________ in organic solvents and ________ in water

soluble, and insoluble

Codeine is an amine molecule that is classified as an opioid narcotic. Codeine binds to receptors in the brain that transmit pain signals causing a reduction in pain sensations in the body. What type of amin is Codeine?

tertiary amine

A ________ is a peptide that contains four amino acids joined together by three peptide bonds.

tetrapeptide

In nicotine (structure shown) the shape of the nitrogen in the pyridine ring is ________ and the shape of the nitrogen in the pyrrolidine ring is ________.

trigonal planar, and trigonal pyramidal

(CH3)2NCH2CH2CH2CH3 has a lower boiling point than CH3CH2CH2CH2NHCH2CH3.

true

A common type of reaction for acyl compounds is substitution.

true

Acidic amino acids have lower p I values than basic amino acids

true

________ are required for normal metabolism but since our cells can not synthesize them, they must be obtained in the diet.

vitamins

Lipids known as ________ provide a protective coating for plants and animals.

waxes

Since amino acids contain a base (NH2 group) and an acid (COOH), proton transfer from the acid to the base forms a salt called a/an ________, which contains both a positive and a negative charge

zwitterson