Biochem Final Review Examkeys/ Clickers

Front 1

5) One of the principal methods that organisms use to obtain energy from chemical
bonds is by ___________.
A) Substitution reactions
B) Dehydration reactions
C) Oxidation/reduction reactions
D) Hydration reactions
E) Addition reactions

Back 1

C

Front 2

9) The largest molecules in living organisms are _________.
A) proteins
B) lipids
C) nucleic acids
D) carbohydrates
E) steroides

Back 2

C

Front 3

12) Which of the following is not an advantage of multicellular organisms over
unicellular ones?
A) The cells of multicellular organisms have a relatively stable environment
B) The cells of multicelllular organisms have a division of labor
C) The cells of multicellular have specialized functions
D) Multicellualr organisms are capable of exploiting the environment more effectively
than unicellular ones.
E) Multicellular organisms are all capable of large scale movement

Back 3

E

Front 4

15) Chemosynthesis is defined as:
A) Synthesis of biomolecules using energy derived from the oxidation of certain minerals
B) Synthesis of specific chemicals
C) Specific chemicals as a source of light for photosynthesis
D) Generation of chemicals from a heat source
E) Synthesis of chemicals from light energy

Back 4

A

Front 5

16) Which area within earth’s biosphere has the largest biomass?
A) Ocean
B) Surface of the continents
C) Air
D) Hydrothermal vents
E) The crust beneath the surface

Back 5

E

Front 6

17) The field of study associated with the investigation of gene expression patterns is
called:
A) Proteomics
B) Bioinformatics
C) Genomics
D) Functional genomics

Back 6

D

Front 7

26) Respiratory assemblies are responsible for the synthesis of ___________.
A) ATP
B) NADH
C) GTP
D) Hydrogen peroxide
E) ADP

Back 7

A

Front 8

28) Which of the following statements is not true of the mitochondrial matrix?
A) It contains enzymes responsible for nucleotide metabolism
B) It contains circular DNA molecules
C) It contains all of the necessary compounds for protein synthesis
D) It has a gel-like consistency
E) It has a high concentration of enzymes and ions

Back 8

A

Front 9

32) Which of the following is not a component of the endomembrane system?
A) Plasma membrane
B) Endoplasmic reticulum
C) Golgi apparatus
D) Lysosomes
E) Ribosomes

Back 9

E

Front 10

34) A hydrogen bond is best defined as:
A) A strong chemical bond between hydrogen and another element
B) A weak chemical bond between hydrogen and another element
C) A relatively strong electrostatic bond between hydrogen and oxygen or nitrogen
D) A weak electrostatic bond between hydrogen and oxygen or nitrogen
E) A bond between two hydrogens

Back 10

C

Front 11

36) Which of the following is not a type of van der Waals force?
A) Dipole-dipole interactions
B) Dipole-induced dipole interactions
C) Induced dipole – induced dipole interactions
D) Chemical bonds
E) Hydrogen bonds

Back 11

D

Front 12

42) The sodium acetate / acetic acid buffer is 0.1 molar in sodium acetate and 0.5 molar
in acetic acid. What is the concentration of the buffer?
A) 0.1 molar
B) 0.5 molar
C) 0.6 molar
D) 0.4 molar
E) Either A or B depending on whether acid or base is being added to the buffer.

Back 12

C

Front 13

is 4.36. What is the pKa of acetic acid?
A) 4.36
B)4.76
C) 7.76
D)3.76
E) 5.76

Back 13

B

Front 14

44) Salt bridges in proteins are an example of _________.
A) Hydrogen bonds
B) Ionic interactions
C) Hydrophobic interactions
D) van der Waals forces
E) London dispersion forces

Back 14

B

Front 15

50) Which of the following species would form a buffer with HPO4-2?
A) H3PO4
B) H2PO4-1
C) CO3-2
D) All would form buffers with HPO4-2
E) Both A and B

Back 15

B

Front 16

53) The course of chemical reactions is determined by three factors. These are enthalpy,
entropy and
A) Heat of reaction
B) Free energy
C) States of matter
D) Bond energy
E) Both A and B are correct

Back 16

B

Front 17

54) Which of the following statements is true of an open system
A) There is an exchange of energy only with the surroundings
B) There is an exchange of matter only with the surroundings
C) There is an exchange of both matter and energy with the surroundings
D) In an open system either matter or energy, but not both may be exchanged with the
surroundings
E) Energy flows only into the system: matter flows out of the system.

Back 17

C

Front 18

55) Which of the following statements is true of a closed system?
A) There is an exchange of energy only with the surroundings
B) There is an exchange of matter only with the surroundings
C) There is an exchange of both matter and energy with the surroundings
D) In an closed system either matter or energy, but not both may be exchanged with the
surroundings
E) Energy flows only into the system: matter flows out of the system.

Back 18

A

Front 19

65) The products of the hydrolysis of ATP are more stable than ATP itself. This
circumstance is due to __________.
A) pH effects
B) Relief of charge-charge repulsions
C) Resonance stabilization of the products
D) Relief of steric strain
E) Both B and C are correct

Back 19

E

Front 20

67) Which of the following thermodynamic properties is pathway dependent?
A) Free energy
B) Entropy
C) Enthalpy
D) Work
E) Both B and C are correct

Back 20

D

Front 21

71) How many molecules of oxygen are required to completely oxidize one mole of
stearic acid ( C17H35COOH)?
A) 18
B) 9
C) 34
D) 45
E) 53

Back 21

E

Front 22

72) Given the following ΔH values calculate the ΔH for the complete combustion of
stearic acid.
ΔH (kal/mol) Compound
-211.4 ( C17H35COOΗ
0 Oxygen
-94 Carbon dioxide
-68.4 Water
A) –49 kal
B) –2096.2 kal
C) –2711.8 kal
D) 0 kal
E) 3071.8 kal

Back 22

C

Front 23

α-Keratin contains this amino acid due to its ability to form this specific bond?
A.Glutamic acid, hydrogen bond
B.Histidine, salt bridge
C.Cysteine, disulfide bridges
D.Lysine, Schiff base crosslinks
E.Methionine, disulfide bridges

Back 23

C

Front 24

Lysyl oxidase affects what level of collagen structure?
A.1
B.2
C.3
D.4
E.All of the above.

Back 24

D

Front 25

Vitamin C affects what level of collagen structure?
A.1
B.2
C.3
D.4
E.All of the above.

Back 25

E

Front 26

5. How would the decrease in pH from 7.4 to 7.2 effect the oxygen saturation curve of Hb?
A.
Shift to the right
B.
Shift to the left
C.
Shift up
D.
Shift down
E.
No effect

Back 26

A

Front 27

6. The T state in hemoglobin binding is stabilized by…
A.
Substrate concentration
B.
O2binding
C.
Salt bridges
D.
H-bonds
E.Active site

Back 27

C

Front 28

7. BPG be best described as:
A.
Negative allosteric effector
B.
Positive allosteric effector
C.
Destabilizes T state of Hb
D.
Contributes to the Bohr effect
E.
It is not an allosteric effector

Back 28

A

Front 29

10. When the substrate concentration is much much greater than the Kmthe reaction is what order (in [S])?
A.
0thorder
B.
1storder
C.
2ndorder
D.
3rdorder
E.
4thorder

Back 29

A
means it is saturated

Front 30

3. Which of the following amino acids lacks a center of asymmetry?
A. Alanine
B. Glycine
C. Valine
D. Isoleucine
E. Aspartic acid

Back 30

B

Front 31

7. Invariant amino acids in a protein are presumed:
A. To be unimportant in the structure and function of the protein B. To be essential to the structure and function of the protein
C) Always to occur at the beginning of the amino acid sequence of an enzyme
D. Always to occur at the end of the amino acid sequence of an enzyme
E. To be part of the prosthetic group.

Back 31

B

Front 32

11. Which of the following statements is true of the Bohr effect?
A. Oxygen is delivered to cells in proportion to their needs
B. Binding of protons to hemoglobin molecules facilitates the release of oxygen
C. Metabolic waste products bond to oxyhemoglobin
D. A and B are both true E. All of the above are true

Back 32

E

Front 33

16. The synthesis of enzymes in response to changing metabolic needs is called A. Enzyme induction
B. Allosteric regulation
C. Negative feedback
D. Zymogen actvation
E. Cooperative binding

Back 33

A

Front 34

17. Which of the following is a coenzyme? A. NADP+
B. Zn++
C. Cu++
D. Insulin
E. Oxytocin

Back 34

A

Front 35

The steady state assumption states that if:

Back 35

The rate of formation of ES is equal to the rate of its degradation over the course of the reaction

Front 36

K1 = the rate constant for ES formation
K2 = the rate constant for ES dissociation
K3 = the rate constant for product formation
20. The expression of the Michaelis constant is equal to: A) (K2 + K3)/K1
B) (K2 + K1)/K3
C) (K1 + K2)/K3
D) (K3 + K1) + K3
E) (K2/K1) + K3

Back 36

A

Front 37

23. Zymogens are a feature of what type of enzymatic control?
A. Genetic control
B. Covalent modification
C. Allosteric regulation
D. Compartmentation E. Protease activation

Back 37

E

Front 38

Chaperonins are
A. Protein inhibitors
B. Molecular motors
C. Protein folding proteins
D. immunoproteins
E. fibrous proteins

Back 38

C

Front 39

27. Specific activity is defined as
A.Enzyme concentration that converts 1 μ mole of substrate to product per minute.
B. Enzyme concentration that converts 1 mole of substrate to product per minute C. The number of I.U. per mg of protein
D. The number of I. U. per gram of protein
E. Enzyme concentration that converts 1 mmole of substrate to product per minute.

Back 39

C

Front 40

32. Fibrous proteins typically have large amounts of:
A. α helix
B. β-pleated sheets
C. Disulfide bridges
D. Salt bridges E. Both A and B are correct

Back 40

E

Front 41

33. The identity and arrangement of amino acids on the surface of a globular protein are important because they may:
A. Interact to form specific binding cavities
B. Stabilize the tertiary structure of the protein
C. Bind regulatory molecules
D. Both A and C are correct E. All of the above are correct

Back 41

E

Front 42

Chymotrypsin cleaves proteins at the carboxyl end of which amino acid?
A. Phenylalanine
B. Arginine
C. Tyrosine
D. Lysine
E both A and C

Back 42

E

Front 43

39. Which of the following amino acids is capable of acting as a general acid or general
base at physiological pH ?
A. Glycine B. Histidine
C. Tyrosine
D. Tryptophan
E. Proline

Back 43

B

Front 44

40. Which of the following amino acids can participate in covalent catalysis?
A. Tryptophan
B. Tyrosine
C. Serine
D. Histidine E. Both C and D are correct

Back 44

E

Front 45

41. Which of the following is a feature of transition metals that makes them efficient
cofactors?
A) Have a high concentration of positive charge
B) Can act as a Lewis acid
C) Have directed valences
D) Can exist as a variety of valence states E) All of the above are correct.

Back 45

E

Front 46

42. The narcotic alkaloid morphine is derived from which amino acid?
A. Serine
B. Threonine C. Tyrosine
D. Valine
E. Cystine

Back 46

C

Front 47

51. In the Lineweaver-Burke double reciprocal plot the vertical intercept is equal to
A. 1/[S]
B. 1/V
C. Km/Vmax D. 1/Vmax
E. –1/Km

Back 47

D

Front 48

52. In the Lineweaver-Burke double reciprocal plot the horizontal intercept is equal to
A. 1/[S]
B. 1/V
C. Km/Vmax
D. 1/Vmax E. –1/Km

Back 48

E

Front 49

55. Osteogenesis Imperfecta affects which amino acid of collagen’s structure? A. Glycine
B. Proline
C. Hydroxyproline
D. Lysine
E. Allysine

Back 49

A

Front 50

56. Lysyl oxidase affects what level of collagen structure?
A. chains
B. triple helix C. cross links
D. disulfide bridges
E. helix

Back 50

C

Front 51

57. Vitamin C affects collagen structure in what way?
A. assists crosslink formation B. required for hydroxylation of certain amino acid residues
C. assists triple helix formation
D. A & B
E. B & C

Back 51

B

Front 52

58. Allysine and lysine react to form;
A. Aldol condensation product
B. Disulfide bridge C. Schiff base
D. Carbamate
E. Amide

Back 52

C

Front 53

61. In a Lineweaver-Burke Double Reciprocal plot Vmax and Km are found by
A. taking the X and Y intercept
B. taking the Y and X intercept
C. taking 1/X and 1/Y intercept
D. taking the 1/Y and 1/X intercept
E. taking the 1/Y and -1/X intercept

Back 53

E

Front 54

63. What form of reversible inhibition is common to allosteric enzymes?
A. Competitive
B. Non-competitive
C. Uncompetitive
D. Mixed
E. B & E

Back 54

E

Front 55

The amino acid responsible for bond cleavage in chymotrypsin is:
A. protonated serine
B. deprotonated serine
C. protonated histidine
D. deprotonated histidine

Back 55

C

Front 56

68. In the R state, Hb has
A. acidic histidines and oxygen B. basic histidines and oxygen
C. BPG
D. acidic histidines and no oxygen
E. basic histidines and no oxygen

Back 56

B

Front 57

72. In Hb the distal histidine (F8)… A. Facilities binding of O2
B. Creates H-bonds with O2
C. Prevents change in oxidative state of Fe2+
D. Reduces Fe3+ to Fe2+
E. Creates a salt bridge with Fe3+

Back 57

A

Front 58

9. The Chymotrypsin catalytic triad includes which of the following amino acids?
A.
His, gly, met
B.
Val, his, ile
C.
Ser, glu, lys
D.
His, ser, asp
E.
Arg, cys, asp

Back 58

D

Front 59

What is the following monosaccharide?
A. D-erythrose
B. D-arabinose
C. D-ribose
D. D-allose
E. D-altrose

Back 59

C

Front 60

Glycosaminoglycans are:
A. Oligosacharides linked via β-glycosidic bonds
B. Linear polymers with disacharides repeating units
C. Oligosacharides linked via β-glycosidic bonds
D. Dglycoprotins with high carbohydrate content
E. Polymer composed of d-glucopuranose residues

Back 60

b

Front 61

Citrate and ATP are allosteric inhibitors of?
A. PFK-1
B. Aldolase
C. PFK-2
D. AMPK
E. Pyruvate kinase

Back 61

A

Front 62

Three the most important substrates for gluconeogenesis are:
A.Lactate, glycerol, alanine
B.Pyruvate, glycerol, glucose
C.Serine, ATP, glucose
D.Glycerol, alanine, pyruvate
E.Glucose, NAD, alanine

Back 62

A or D

Front 63

12. Arsenate can replace phosphate in the step of glycolysis that produces?
A.Glycerate-2-phosphate
B.Glyceraldehyde-3-phosphate
C.Phosphoenolpyruvate
D.Glycerate-1,3-phosphate
E.Pyruvate

Back 63

D

Front 64

13. 6-fluoro-D-glucose prevents formation of?
A.Glycerate-2-phosphate
B.Glyceraldehyde-3-phosphate
C.Phosphoenolpyruvate
D.Glucose-6-phosphate
E.Fructose-6-phosphate

Back 64

E

Front 65

14. Compounds responsible for regulation of gluconeogenesis are all except for?
A.Cortisol
B.Pyruvate carboxylase
C.Insulin
D.Glucose-6-phosphatase
E.All of the above

Back 65

E

Front 66

Which of the following statements is TRUE about the 6-membered ring form of D–glucose?
A. It is a furanose
B. It results from bond formation between C-1 and C-6
C. It is not a common form in a aqueous solution
D. It is the addition product of the hydroxy on C-5 to the carbonylE. None of the above is true

Back 66

D

Front 67

The reducing end of a disaccharide or a polysaccharide is?
A.
B. The end with an anomeric carbon that cannot be oxidized
The end with a free anomeric carbon
C. The end without an anomeric carbon
D. The glycosidic linkage
E. None of the above is true

Back 67

A

Front 68

Which of the following statements is NOT TRUE about proteoglycans?
A. They are sugars bound to proteins
B. They are large in size
C. They are present in extracellular matrix
D. They comprise the cell wall of gram
E. They are heavily glycosylated proteins

Back 68

D

Front 69

Which of the following polysaccharides is known for binding exceptionally large amounts of water?
A. Cellulose
B. Glycogen
C. Starch
D. Heparin
E. Amylase

Back 69

D

Front 70

In glycoproteins carbohydrate is most often linked to threonine, asparagines or…?
A. serine
B. Lysine
C. Aspartic acid

Back 70

A

Front 71

The prosthetic group associated with E2 in PDH complex is?
A. Thiamine pyrophosphate
B. FAD
C.Lipoylamide
D. Co-A
E. NAD+

Back 71

C

Front 72

What types of enzymes catalyzes dephosphorylation reactions?
A. Reductases
B. Isomerases
C. Kinases
D. Ligases
E.
Hydrolases

Back 72

E

Front 73

The major sugar used to transport sugar in lobsters is?
A.Trehalose
B. Sucrose
C. Lactose
D. Fructose
E. Glucose

Back 73

A

Front 74

Keto-enol tautomerism is involved in which of the following reactions?
A. phosphoglucoisomerase
B. enolase
C. Pyruvate kinase
D. A and B
E.
A and C

Back 74

E

Front 75

The ene-diol is an intermediate in which reaction?
A.Aldose – ketose isomerization
B. PEP to Pyruvate
C. Decarboxylation
D. Aldolase reaction
E. Both A and B are correct

Back 75

A

Front 76

The Pasteur effect refers to…
A. The utilization of more glucose during exercize
B. The utilization of more glucose by cancer cells
C. The utilization of less glucose in high O2 conditions
D. The relationship of the TCA cycle to oxidative phosphorylation
E. All of the above

Back 76

E

Front 77

The Cori Cycle is the..?
A. Transport of pyruvate from the muscle to the liver for glycolysis
B. Transport of pyruvate from the muscle to the liver for gluconeogenesis
C. Transport of lactate from the muscle to the liver for glycolysis
D.Transport of lactate from the muscle to the liver for gluconeogenesis
E. 2 + 2 pi electron cyclization

Back 77

D

Front 78

Which of the following is true about the reactions about the reactions catalyzed by PFK1 and FBP1?
A. Only phosphofructokinase-1 catalyzes an exergonic reaction
B. Phosphofructokinase-1 and fructose 1,6-bisphosphatase are inhibited by high levels of AMP
C.The fructose 1,6-bisphosphatase reaction favors gluconeogenesis
D. The function of these two reactions is to act as a futile cycle

Back 78

C

Front 79

What effect does glucagon have on carbohydrate metabolism?
A. It inhibits glycolysis
B. It stimulates gluconeogenesis
C. It inhibits PFK1
D. It stimulates FBP2
E.
All of the above

Back 79

E

Front 80

The first reaction of the citric acid cycle, which generates citrate, is?
A. Dehydration reaction
B. Reduction reaction
C.Condensation reaction
D. Oxidative decarboxylation reaction
E. Elimination reaction

Back 80

C

Front 81

Which of the following is an oxidizing agent in fermentation?
A. Lactate
B. Glucose
C. NADH
D.Pyruvate
E. NAD+

Back 81

D

Front 82

How many oxidations steps are there in the citric acid cycle?
A. 1
B. 2
C. 3
D. 4
E. 5

Back 82

D

Front 83

Which of the following is a cofactor for the conversion of succinate to fumarate ?
A. NAD+
B.FAD
C. GDP
D. ADP
E. CoASH

Back 83

b

Front 84

Which of the following reactions involves a substrate level phosphorylation?
A. Pyruvate -- AcetylCoA
B.Succinyl CoA - Succinate
C. Citrate - Isocitrate
D. Fumarate - Malate
E. Malate --- Oxaloacetate

Back 84

B

Front 85

The overall reaction catalyzed by pyruvate dehydrogenase is which of the following?
A. CH3COCHO + NAD+ + CoASH --> CH3CHOHSCoA + NADH + CO2
B. CH3COCOO- + FAD +CoASH --> CH3CH2SCoA + NADH + CO2
C. CH3COCOO- + NAD+ + CoASH --> CH3COSCoA + NADH + CO2
D. CH3CH(OH)COO- + NADH + CoASH --> CH3CH(OH)COSCoA + NAD+
E. None of the above is correct

Back 85

C

Front 86

How many α-keto acids are found in the citric acid cycle?
A. 1
B. 2
C. 3
D. 4
E. 5

Back 86

B

Front 87

Which of the following conversions is an anaplerotic reaction of the citric acid
cycle?
A. Pyruvate to oxaloacetate
B. Certain amino acids to succinyl CoA
C. Glutamate to α-ketoglutarate
D. Aspartate to oxaloacetate
E.All of the above are correct

Back 87

E

Front 88

The reaction involving thioesters in the citric acid cycle include:
A. 1, 2, 3
B. 1, 3, 4
C. 1,4,5
D. 1, 5, 6
E. 1,6, 7

Back 88

C

Front 89

The number of tricarboxylic acids in the tricarboxylic acid cycle is?
A. 1
B. 2
C. 4
D. 6
E. 8

Back 89

B

Front 90

The number of hydroxy acids in the citric acid cycle is?
A. 1
B. 2
C. 3
D. 4
E. 5

Back 90

C

Front 91

The number of ATP equivalents required to synthesize one glucose molecule from two pyruvates is?
A. 2
B. 4
C. 6
D. 11
E. 12

Back 91

D