A TEST BANK FOR PRINCIPLES OF BIOCHEMISTRY
4TH EDITION
BY (HORTON) LATEST 2025
,Contents
Chapter 1 Introduction to Biochemistry 1
Chapter 2 Water 10
Chapter 3 Amino Acids and the Primary Structures of Proteins 27
Chapter 4 Proteins: Three-Dimensional Structure and Function 46
Chapter 5 Properties of Enzymes 65
Chapter 6 Mechanisms of Enzymes 85
Chapter 7 Coenzymes and Vitamins 104
Chapter 8 Carbohydrates 119
Chapter 9 Lipids and Membranes 137
Chapter 10 Introduction to Metabolism 153
Chapter 11 Glycolysis 169
Chapter 12 Gluconeogenesis, The Pentose Phosphate Pathway,
and Glycogen Metabolism 185
Chapter 13 The Citric Acid Cycle 199
Chapter 14 Electron Transport and Oxidative Phosphorylation 213
Chapter 15 Photosynthesis 227
Chapter 16 Lipid Metabolism 241
Chapter 17 Amino Acid Metabolism 256
Chapter 18 Nucleotide Metabolism 269
Chapter 19 Nucleic Acids 284
Chapter 20 DNA Replication, Repair, and Recombination 300
Chapter 21 Transcription and RNA Processing 315
Chapter 22 Protein Synthesis 330
Chapter 23 Recombinant DNA Technology 348
,Chapter 1 Introduction to Biochemistry
1) Which elements account for more than 97% of the weight of most organisms?
A) C, H, N, Mg, O, S
B) C, H, N, O, P, S
C) C, H, N
D) Fe, C, H, O, P
E) Ca2+, K+, Na+, Mg2+, Cl-
Answer: B
Page Ref: Section 2
2) Proteins in biological membranes may be
A) porous.
B) attached to the membrane surface.
C) span the membrane.
D) All of the above
E) B and C only
Answer: D
Page Ref: Section 3
3) Which statement about cellulose is false?
A) It is the most abundant polysaccharide in nature.
B) Its monomers are joined by glycosidic bonds.
C) It is present in the stems of flowering plants.
D) The hydroxyl groups of neighboring cellulose molecules interact to form strong, insoluble
fibers.
E) It is a branched polymer of glucose.
Answer: E
Page Ref: Section 3
1
, 4) When Keq of a reaction = 1, then
A) the forward reaction is faster than the reverse reaction.
B) the reverse reaction is faster than the forward reaction.
C) the forward and reverse reaction rate constants are equal.
D) more products are formed than reactants.
E) fewer products are formed than reactants.
Answer: C
Page Ref: Section 4
5) Which statement is true about a reaction with an equilibrium constant, Keq, equal to 1000?
A) The forward rate constant is 1000 times greater than the reverse rate constant.
B) The forward rate constant is 3 times greater than reverse rate constant.
C) The forward rate constant is 1000 times smaller than the reverse rate constant.
D) The forward rate constant is 3 times smaller than the reverse rate constant.
E) There is not enough information given to compare the forward and reverse rate constants.
Answer: A
Page Ref: Section 4
6) The study of the energy changes during metabolic reactions is called .
A) bioinformatics
B) metabodynamics
C) thermometrics
D) bioenergetics
E) biological heat dynamics
Answer: D
Page Ref: Section 4
7) A spontaneous chemical reaction always has a change.
A) positive Gibbʹs free energy
B) negative Gibbʹs free energy
C) positive enthalpy
D) negative enthalpy
E) positive entropy
Answer: B
Page Ref: Section 4
2
4TH EDITION
BY (HORTON) LATEST 2025
,Contents
Chapter 1 Introduction to Biochemistry 1
Chapter 2 Water 10
Chapter 3 Amino Acids and the Primary Structures of Proteins 27
Chapter 4 Proteins: Three-Dimensional Structure and Function 46
Chapter 5 Properties of Enzymes 65
Chapter 6 Mechanisms of Enzymes 85
Chapter 7 Coenzymes and Vitamins 104
Chapter 8 Carbohydrates 119
Chapter 9 Lipids and Membranes 137
Chapter 10 Introduction to Metabolism 153
Chapter 11 Glycolysis 169
Chapter 12 Gluconeogenesis, The Pentose Phosphate Pathway,
and Glycogen Metabolism 185
Chapter 13 The Citric Acid Cycle 199
Chapter 14 Electron Transport and Oxidative Phosphorylation 213
Chapter 15 Photosynthesis 227
Chapter 16 Lipid Metabolism 241
Chapter 17 Amino Acid Metabolism 256
Chapter 18 Nucleotide Metabolism 269
Chapter 19 Nucleic Acids 284
Chapter 20 DNA Replication, Repair, and Recombination 300
Chapter 21 Transcription and RNA Processing 315
Chapter 22 Protein Synthesis 330
Chapter 23 Recombinant DNA Technology 348
,Chapter 1 Introduction to Biochemistry
1) Which elements account for more than 97% of the weight of most organisms?
A) C, H, N, Mg, O, S
B) C, H, N, O, P, S
C) C, H, N
D) Fe, C, H, O, P
E) Ca2+, K+, Na+, Mg2+, Cl-
Answer: B
Page Ref: Section 2
2) Proteins in biological membranes may be
A) porous.
B) attached to the membrane surface.
C) span the membrane.
D) All of the above
E) B and C only
Answer: D
Page Ref: Section 3
3) Which statement about cellulose is false?
A) It is the most abundant polysaccharide in nature.
B) Its monomers are joined by glycosidic bonds.
C) It is present in the stems of flowering plants.
D) The hydroxyl groups of neighboring cellulose molecules interact to form strong, insoluble
fibers.
E) It is a branched polymer of glucose.
Answer: E
Page Ref: Section 3
1
, 4) When Keq of a reaction = 1, then
A) the forward reaction is faster than the reverse reaction.
B) the reverse reaction is faster than the forward reaction.
C) the forward and reverse reaction rate constants are equal.
D) more products are formed than reactants.
E) fewer products are formed than reactants.
Answer: C
Page Ref: Section 4
5) Which statement is true about a reaction with an equilibrium constant, Keq, equal to 1000?
A) The forward rate constant is 1000 times greater than the reverse rate constant.
B) The forward rate constant is 3 times greater than reverse rate constant.
C) The forward rate constant is 1000 times smaller than the reverse rate constant.
D) The forward rate constant is 3 times smaller than the reverse rate constant.
E) There is not enough information given to compare the forward and reverse rate constants.
Answer: A
Page Ref: Section 4
6) The study of the energy changes during metabolic reactions is called .
A) bioinformatics
B) metabodynamics
C) thermometrics
D) bioenergetics
E) biological heat dynamics
Answer: D
Page Ref: Section 4
7) A spontaneous chemical reaction always has a change.
A) positive Gibbʹs free energy
B) negative Gibbʹs free energy
C) positive enthalpy
D) negative enthalpy
E) positive entropy
Answer: B
Page Ref: Section 4
2
