Deck 22: Biochemistry

Question 1

Which of the following does not correctly describes the structure of glucose?

A)carbohydrate
B)dissaccharide
C)aldose
D)simple sugar
E)has $\alpha$ and $\beta$ forms

Answer 1

dissaccharide

Question 2

In simple sugars,every carbon but one contains a hydroxyl group; the remaining carbon is double bonded to an oxygen atom as a carbonyl group.What type of sugar has the carbonyl group in the carbon chain?

A)Kamalose
B)Polysaccharide
C)Disaccharide
D)Aldose
E)Ketose

Answer 2

Ketose

Question 3

Consider the following amino acid structures:

Glycine alanine serine
Identify the C-terminal acid and the N-terminal acid in the following dipeptide:
C-terminal acid N-terminal acid

A)glycine alanine
B)glycine serine
C)alanine serine
D)alanine glycine
E)serine glycine

Answer 3

alanine glycine

Question 4

Which of the following is the best definition of the term amino acid?

A)A carboxylic acid containing both an amine group and a variable alkyl group
B)A substance that yields hydronium ions in aqueous solution
C)A substance that donates protons in a chemical reaction
D)A substance that forms covalent bonds by accepting a pair of electrons
E)An organic acid containing the carboxyl group,having the general formula RCOOH

Question 5

How many different tripeptides composed of three different amino acids can be formed if glycine,alanine,and valine are mixed together and peptide bonds are allowed to form in all possible combinations?

A)2
B)3
C)4
D)6
E)8

Question 6

Which of the following is the best definition of the term enzyme?

A)A molecule made of two or more simple sugar molecules
B)A substance that is found in living organisms and is insoluble in water but soluble in nonpolar solvents
C)A lipid having three cyclohexane rings and one cyclopentane ring
D)A small molecule characterized by a carboxyl group at one end of the carbon chain and an amine group on the carbon next to the carboxyl group
E)A catalyst that controls chemical reactions in a living system

Question 7

Which of the following statements is correct?
(i)Chemical reactions in a living system are each controlled by a catalyst called an enzyme.
(ii)The substrate is the reactant that the enzyme helps convert to product.
(iii)The catalytic properties of an enzyme exist at the site.

A)i only
B)ii only
C)iii only
D)i and ii
E)All are correct statements.

Question 8

Consider the induced fit model of enzyme activity.Which of the following statements about this model is false?

A)The shape of the substrate is a close,but not exact,match to the shape of the active site of the enzyme.
B)As the substrate binds to the enzyme,either or both molecules change shape slightly.
C)The distortion of the shape of the substrate may be a factor in catalyzing the reaction.
D)After the products are released,the enzyme returns to its original shape.
E)The substrate and enzyme bind irreversibly.

Question 9

What is the name of the location that binds the enzyme's substrate during the reaction that follows?

A)Disulfide linkage
B)Messenger RNA
C)Substrate binding location
D)Active site
E)Skinner's linkage

Question 10

Which of the following is the best explanation of why the $\alpha$ -helix and the $\beta$ -pleated sheet are the most stable protein conformations possible?

A)Both structures reflect a maximum amount of hydrogen bonding
B)Their local conformations have amide bonds that can break and reform
C)All of the amino acids polymerize,primarily those that are large and/or polar,to form an $\alpha$ -helix
D)The secondary structure is strengthened by disulfide linkages
E)The electrons in the nitrogen atoms in these structures exist in excited states

Question 11

In simple sugars,every carbon but one contains a hydroxyl group; the remaining carbon is double bonded to an oxygen atom as a carbonyl group.What type of sugar has the carbonyl at the end of the carbon chain?

A)Cretose
B)Polysaccharide
C)Disaccharide
D)Aldose
E)Ketose

Question 12

Which of the following statements is correct?
(i)The shape and polarity of the active site of an enzyme allows only a few dozen substrate molecules to bind reversibly to the enzyme at a time.
(ii)If a substrate remains bound to an enzyme,that enzyme molecule can no longer function as a catalyst.
(iii)Military nerve gases are examples of irreversible inhibitors.

A)i only
B)ii only
C)iii only
D)i and ii
E)ii and iii

Question 13

Which of the following is the best definition of the term enzyme substrate?

A)A catalyst that controls chemical reactions in a living system
B)A location that binds the reactant during a chemical reaction
C)A rigid,rod-like protein
D)The reactant in an enzyme-catalyzed reaction
E)A macromolecule made of deoxyribonucleic acid and ribonucleic acid

Question 14

Which of the following is the best definition of a protein's primary structure?

A)The order of amino acids in the protein
B)A description of the bends in the protein chain
C)The local conformation of the backbone chain of the protein
D)The arrangement of protein chains relative to one another.
E)The number of peptide linkages between amino acids and a list of the R groups

Question 15

Consider the following description:
"The bends and folds in the protein chain were stabilized by both
Disulfide bridges and hydrophobic interactions."
This is a description of which type of protein structure?

A)primary
B)secondary
C)tertiary
D)quaternary

Question 16

How many different substrate molecules are normally catalyzed by a single enzyme?

A)One
B)Ten
C)One hundred
D)One million
E)36 million

Question 17

Which of the following is the best definition of the term protein?

A)The class of polymeric molecules with molar masses from about 5,000 g/mole on up
B)An amino acid polymer typically containing more than 40 amino acids
C)A chemical compound formed by bonding two or more monomers
D)A compound consisting of a carbonyl group bonded to a hydrogen on one side and a hydrogen,alkyl,or aryl group on the other
E)A carboxylic acid containing both an amine group and a variable alkyl group

Question 18

Consider the following general structure. If the R group were HO-CH₂-,this compound would be classified as:

A)nonpolar,neutral
B)polar,neutral
C)polar,acidic
D)polar,basic

Question 19

Consider the following general formula. One molecule with an R group of HO-CH₂-,combines with another molecule with an R group of HS-CH₂-.Which of the following could correctly represent the product of this reaction?

A)Ser-Cys
B)Cys-Ser
C)S-C
D)C-S
E)Any of the above are a possibility.

Question 20

If a substrate remains bound to an enzyme,that enzyme molecule is no longer a catalyst.What is the name of the irreversibly bound substrate?

A)Contaminant
B)Inhibitor
C)Decatalyzer
D)Binder
E)Hauer's substrate

Question 21

Which of the following bases is not found in DNA?

A)Thymine
B)Guanine
C)Cytosine
D)Uracil
E)Adenine

Question 22

(i)are triacylglycerols that are solids at room temperature; (ii)are triacylglycerols that are liquids at room temperature.
I ii

A)waxes fats
B)waxes oils
C)oils waxes
D)fats oils
E)oils fats

Question 23

What is the name of the sugar that is also known as levulose or fruit sugar?

A)Ribose
B)Glucose
C)Fructose
D)Sucrose
E)Lactose

Question 24

Which of the following are the two types of nucleic acids in all living systems?
(i)Deoxyribonucleic acid
(ii)Gluconucleic acid
(iii)Ribonucleic acid
(iv)Fructonucleic acid

A)i and ii
B)i and iii
C)i and iv
D)ii and iii
E)ii and iv

Question 25

The polysaccharides cellulose,starch,and glycogen share a common monomer.What is that monomer?

A)Lactose
B)Sucrose
C)Ribose
D)Fructose
E)Glucose

Question 26

Which of the following correctly lists the three parts of a nucleotide found in DNA?

A)ribose,phosphate,uracil
B)ribose,phosphate,thymine
C)deoxyribose,phosphate,adenine
D)deoxyribose,phosphate,uracil

Question 27

Which of the following monosaccharides combine to make the disaccharide sucrose?
(i)Glucose
(ii)Fructose
(iii)Ribose
(iv)Galactose

A)i and ii
B)i and iii
C)i and iv
D)ii and iii
E)ii and iv

Question 28

Which of the following carbohydrates are polysaccharides?
(i)Sucrose
(ii)Cellulose
(iii)Starch
(iv)Glycogen
(v)Fructose

A)i and ii
B)i and v
C)ii and iii
D)ii,iii,and iv
E)ii,iii,iv,and v

Question 29

Which of the following statements is/are incorrect?
(i)Fats and oils are mainly esters of long-chain carboxylic acids
(ii)Long-chain carboxylic acids are called oily acids
(iii)The alcohol part of the ester in fats and oils comes from a dihydroxyl alcohol

A)i only
B)ii only
C)iii only
D)i and ii
E)ii and iii

Question 30

Which of the following is the structural feature that characterizes a steroid?

A)A RCOOR' group
B)A RCOR' group
C)A cyclohexane ring
D)A benzene ring and three cyclohexane rings fused
E)A cyclopentane ring and three cyclohexane rings fused

Question 31

What molecular structure is shown below?

A)Thymine
B)Adenine
C)Cytosine
D)Uracil
E)Guanine

Question 32

Which of the following bases is not found in RNA?

A)Thymine
B)Guanine
C)Cytosine
D)Uracil
E)Adenine

Question 33

Which of the following is the best definition of the term lipid?

A)A molecule made of two or more simpler sugar molecules
B)A substance that is found in living organisms and is insoluble in water but soluble in nonpolar solvents
C)A nucleic acid monomer
D)A small molecule characterized by a carboxyl group at one end of the carbon chain and an amine group on the carbon next to the carboxyl group
E)A catalyst that controls chemical reactions in a living system

Question 34

Which of the following is classified as a lipid?
(i)fats
(ii)oils
(iii)waxes
(iv)steroids

A)i only
B)ii only
C)iii only
D)iv only
E)All are lipids

Question 35

Which of the following statements is/are incorrect?
(i)Like fats,phospholipids are esters of glycerol
(ii)A phospholipid has three fatty acid residues
(iii)Phospholipids have a nonpolar head and long,polar tails

A)i only
B)i and ii
C)ii and iii
D)All statements are correct
E)All statements are incorrect

Question 36

Which of the following make up the three components of a nucleotide?
(i)Nitrogen base
(ii)Sugar
(iii)Phosphate group
(iv)Amino acid
(v)Steroid

A)i,ii,and iii
B)i,ii,and iv
C)ii,iii,and v
D)ii,iv,and v
E)iii,iv,and v

Question 37

Which of the following make up the three major subclasses of lipids?
(i)Amino acids and proteins
(ii)Mono-,di-,and polysaccharides
(iii)Fats,oils,and phospholipids
(iv)Waxes
(v)Steroids

A)i,ii,and iii
B)i,iii,and iv
C)ii,iii,and iv
D)ii,iii,and v
E)iii,iv,and v

Question 38

Which of the following monosaccharides combine to make the disaccharide lactose?
(i)glucose
(ii)fructose
(iii)ribose
(iv)galactose

A)i and ii
B)i and iii
C)i and iv
D)ii and iii
E)ii and iv

Question 39

Which of the following statements is/are correct?
(i)Some waxes are esters of fatty acids with an alcohol portion that is a monohydroxyl alcohol with a long carbon chain
(ii)Some waxes serve as a water-resistant coating on skin,fur,and feathers,but most waxes are structural
(iii)The general structure for many waxes is that of an ether

A)i only
B)i and ii
C)i and iii
D)ii and iii
E)i,ii,and iii

Question 40

Which of the following is/are classified as (a)steroid(s)?
(i)Cholesterol
(ii)Lecithin
(iii)Lanolin

A)i only
B)ii only
C)iii only
D)i and iii
E)i,ii,and iii

Question 41

What molecular structure is shown below?

A)Thymine
B)Adenine
C)Cytosine
D)Uracil
E)Guanine

Question 42

Which of the following base pairs are complementary?
(i)AT
(ii)AC
(iii)GC
(iv)AU
(v)TG

A)i and ii
B)iii and iv
C)i,iii,and iv
D)ii,iv,and v
E)i,ii,iii,and iv

Question 43

Which of the following is the term used to describe the process that results in two new DNA molecules? Each new DNA molecule is formed from one strand of the original DNA and one newly constructed complementary strand.

A)Mutation
B)Translation
C)Recombination
D)Replication
E)Transcription

Question 44

Which of the following is the term used to describe the process by which the amino acid sequence in a protein molecule is constructed from information carried in messenger RNA?

A)Mutation
B)Translation
C)Recombination
D)Replication
E)Transcription

Question 45

Which of the following is the term used to describe the process where an appropriate DNA molecule makes a "photocopy" of the protein plan in the form of a complementary messenger RNA molecule?

A)Mutation
B)Translation
C)Recombination
D)Replication
E)Transcription