Biochemistry- Complete Exam Test Bank - Exam Questions &
Answers
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
,8) Prokaryotes |are |valuable |tools | for | biochemists |because
A) E. |coli |is |well-studied | and |typical |of |prokaryotes.
B) they |contain | as |many | genes |as |eukaryotic |cells.
C) many | of |their | chromosomes |are | sequenced.
D) they |are |not |very |diverse |organisms.
E) All |of |the |above
Answer: | C
Page |Ref: | Section | 6
9) Which |cellular |component |carries |out |oxidation |reactions, |some |of |which |produce
|hydrogen |peroxide?
A) peroxisomes
B) mitochondria
C) chloroplasts
D) lysosomes
E) vacuoles
Answer: | A
Page |Ref: | Section | 8
10) Why |is |it |important |that |the |enzymes |in |lysosomes |are |more |active |at |acidic |pH |than |at
|neutral |pH?
A) Since |lysosomes |are |primarily |found |in |the |stomach |acid |of |mammals, |their
|pH |dependence |allows |for |maximum |efficiency |for |the |digestion |of
|foodstuffs.
B) It | prevents |their |diffusion |out |of |the |lysosomes.
C) It | maximizes |the |interaction |with |their | substrates |which | are |always | bases.
D) It | prevents |them | from |accidentally |degrading | the |macromolecules | in |the |cytosol.
E) It | allows | for | regulation | of |their | uptake | by |the |mitochondria.
Answer: | D
Page |Ref: | Section | 8
11) Molecules |from |living |cells |cannot |be |synthesized |outside |of |living
cells. |Answer: | FALSE
|
Page |Ref: | Section | 1
12) Fermentation |in |the |absence |of |cells |demonstrated |that |metabolic |processes |were |chemical
|in |nature.
Answer: | TRUE
Page |Ref: | Section | 1
3
, 13) Enzymes | are |protein | catalysts |that | form |an |intermediate | with |a | substrate |that | fits |into | it.
Answer: | TRUE
Page |Ref: | Section | 1
14) The |modified |lock-and-key |theory |of |enzyme |action |proposed |by |Emil |Fischer |has
|been |completely |replaced |by |more |modern |ideas |of |catalysis.
Answer: | FALSE
Page |Ref: | Section | 1
15) Enzymes |are |not |as |efficient |as |most |catalysts |used |in |organic |chemistry, |since |they
|must |function |at |body |temperature.
Answer: | FALSE
Page |Ref: | Section | 1
16) Bioinformatics |has |permitted |rapid |advances |in |our |understanding |of
|structural |macromolecules |from |living |cells.
Answer: | TRUE
Page |Ref: | Section | 1
17) The |role |of |DNA |as |the |genetic |material |was |confirmed |by |transforming |Streptococci |in
|experiments |performed |several |years |after |the |famous |Watson |and |Crick |description |of
|DNA |structure.
Answer: | FALSE
Page |Ref: | Section | 1
18) Crick |referred |to |the |flow |of |information |from |nucleic |acid |to |protein |as |the |Central
Dogma. |Answer: | TRUE
|
Page |Ref: | Section | 1
19) Functional |groups |describe |one |or |more |portions |of |organic |compounds |found |in |living
cells. |Answer: | TRUE
|
Page |Ref: | Section | 2
20) A |phosphate |ester |contains |a |phosphate |functional
group. |Answer: | TRUE
|
Page |Ref: | Section | 2
21) Under |most |biological |conditions, |acid |groups |and |amino |groups |are |fully
protonated. |Answer: | FALSE
|
Page |Ref: | Section | 2
4
Answers
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
,8) Prokaryotes |are |valuable |tools | for | biochemists |because
A) E. |coli |is |well-studied | and |typical |of |prokaryotes.
B) they |contain | as |many | genes |as |eukaryotic |cells.
C) many | of |their | chromosomes |are | sequenced.
D) they |are |not |very |diverse |organisms.
E) All |of |the |above
Answer: | C
Page |Ref: | Section | 6
9) Which |cellular |component |carries |out |oxidation |reactions, |some |of |which |produce
|hydrogen |peroxide?
A) peroxisomes
B) mitochondria
C) chloroplasts
D) lysosomes
E) vacuoles
Answer: | A
Page |Ref: | Section | 8
10) Why |is |it |important |that |the |enzymes |in |lysosomes |are |more |active |at |acidic |pH |than |at
|neutral |pH?
A) Since |lysosomes |are |primarily |found |in |the |stomach |acid |of |mammals, |their
|pH |dependence |allows |for |maximum |efficiency |for |the |digestion |of
|foodstuffs.
B) It | prevents |their |diffusion |out |of |the |lysosomes.
C) It | maximizes |the |interaction |with |their | substrates |which | are |always | bases.
D) It | prevents |them | from |accidentally |degrading | the |macromolecules | in |the |cytosol.
E) It | allows | for | regulation | of |their | uptake | by |the |mitochondria.
Answer: | D
Page |Ref: | Section | 8
11) Molecules |from |living |cells |cannot |be |synthesized |outside |of |living
cells. |Answer: | FALSE
|
Page |Ref: | Section | 1
12) Fermentation |in |the |absence |of |cells |demonstrated |that |metabolic |processes |were |chemical
|in |nature.
Answer: | TRUE
Page |Ref: | Section | 1
3
, 13) Enzymes | are |protein | catalysts |that | form |an |intermediate | with |a | substrate |that | fits |into | it.
Answer: | TRUE
Page |Ref: | Section | 1
14) The |modified |lock-and-key |theory |of |enzyme |action |proposed |by |Emil |Fischer |has
|been |completely |replaced |by |more |modern |ideas |of |catalysis.
Answer: | FALSE
Page |Ref: | Section | 1
15) Enzymes |are |not |as |efficient |as |most |catalysts |used |in |organic |chemistry, |since |they
|must |function |at |body |temperature.
Answer: | FALSE
Page |Ref: | Section | 1
16) Bioinformatics |has |permitted |rapid |advances |in |our |understanding |of
|structural |macromolecules |from |living |cells.
Answer: | TRUE
Page |Ref: | Section | 1
17) The |role |of |DNA |as |the |genetic |material |was |confirmed |by |transforming |Streptococci |in
|experiments |performed |several |years |after |the |famous |Watson |and |Crick |description |of
|DNA |structure.
Answer: | FALSE
Page |Ref: | Section | 1
18) Crick |referred |to |the |flow |of |information |from |nucleic |acid |to |protein |as |the |Central
Dogma. |Answer: | TRUE
|
Page |Ref: | Section | 1
19) Functional |groups |describe |one |or |more |portions |of |organic |compounds |found |in |living
cells. |Answer: | TRUE
|
Page |Ref: | Section | 2
20) A |phosphate |ester |contains |a |phosphate |functional
group. |Answer: | TRUE
|
Page |Ref: | Section | 2
21) Under |most |biological |conditions, |acid |groups |and |amino |groups |are |fully
protonated. |Answer: | FALSE
|
Page |Ref: | Section | 2
4
