Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

CHELE > Biochem > Flashcards

Biochem Flashcards

1
Q

Glucose and fructose are examples of
A. double sugars
B. disaccharides
C. single sugars
D. polysaccharides

A

c

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

(CH2O)n is the molecular formula for
which type of macromolecules?
A. Proteins
B. Lipids
C. Carbohydrates
D. Nucleic Acid

A

c

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Which of the following is NOT a
polysaccharide?
A. Glycogen
B. Starch
C. Sucrose
D. Cellulose

A

c

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are used in animals as a source of
quick energy that can be stored in the
liver and muscles ？
A. Proteins
B. Nucleic acids
C. Carbohydrates
D. Lipids

A

c

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Sugars, starches, and cellulose belong
to which major class of biological
molecules?
A. Nucleic acids
B. carbohydrates
C. lipids
D. polypeptides

A

b

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Plants like sugar cane and sugar beets store
the energy as simple sugars. Other plants,
like corn and potatoes, store the energy as
more complex sugars called?
A. carbohydrates
B. calories
C. starches
D. cellulose

A

c

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Which macromolecule does not
dissolve in water?
A. proteins
B. lipids
C. carbohydrates
D. nucleic acids

A

b

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the monomers of lipids?
A. Amino acids
B. Simple sugars
C. Fatty acids and glycerol
D. Nucleic acids

A

c

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Lipids are used by the body to perform all
of the following functions EXCEPT:
A. membrane structural material.
B. enzyme action.
C. insulation.
D. a rich energy source.

A

b

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What type of organic substances are
fats?
A. nucleic acid
B. carbohydrate
C. protein
D. lipids

A

d

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Fats that have fatty acids with only single
covalent bonds in their carbon skeletons
are
A. saturated
B. unsaturated
C. found in plants instead of animals
D. liquid at room temperature

A

a

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Which of the following is a polymer?
A. nucleic acid
B. fatty acid
C. Amino acid
D. Glycerol

A

a

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

This biological macromolecule is
responsible for controlling the activity of the
cell, and it stores and transports genetic
information.
A. Carbohydrate
B. Nucleic acid
C. Water
D. Glucose

A

b

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are described as the “building
blocks of Protein”?
A. Fiber
B. Lipids
C. Amino Acids
D. Nutrients

A

c

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Proteins are ___ made of amino
acid _____ .
A. monomers; polymers
B. polymers; polypeptides
C. polymers; monomers
D. monomers; molecules

A

c

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

In this type of structure, most of carbonyl
groups of peptide bonds forms a hydrogen
bond with the amide nitrogen of another
peptide bond four amino acids further down
the polypeptide chain:
A. Alpha-helix
B. Beta-sheet
C. Beta-turn
D. Quaternary

A

a

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

The isoelectric point of an amino acid is defined
as the pH
A. where the molecule carries no electric charge
B. where the carboxyl group is uncharged
C. where the amino group is uncharged
D. of maximum electrolytic mobility

A

a

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

When the amino acid alanine (Rgroup is CH3) is added to a solution
with a pH of 7.3, alanine becomes
A. a cation
B. nonpolar
C. a zwitterions
D. an anion

A

d

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

The term “SALTING IN” refers to?
A.Changes in an amino acid’s isoelectric
point.
B.Increasing the solubility of a protein in
solution by adding ions.
C.The use of a liquid bridge in an
electrochemical cell.
D. The ionization of a strong acid.

A

b

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

The local spatial arrangement of a
polypeptide’s backbone atoms without regard
to the conformation of its side chains can be
called as
A. Primary structure
B. Secondary structure
C. Tertiary structure
D. Quaternary structure

A

b

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Which of the following amino acids are
more likely to be found in a protein’s
interior away from aqueous solvent
molecules?
A. Val, Leu, Ile, Met, and Phe
B. Ser, Thr, Asn, Gln, and Tyr
C. Arg, His, Lys, Asp, and Glu
D. All of the above.

A

a

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Which of the following is (are) true of -
turns in proteins?
A. It is a 180º turn of four amino acids.
B.Glycine and proline are frequently
found there.
C.Are used as connecting turns of -
helix
D. All of the above

A

d

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

The primary stabilizing force of
protein secondary structure is:

a. Ionic bonds.
b. Covalent bonds.
c. Van der Waals forces.
d. Hydrogen bond

A

d

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Two types of beta-pleated sheets can be
called:

A

parallel and antiparallel

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Which of the following is NOT a characteristic
of a globular protein?
A. Polypeptide chain in extended, long
sheets
B. Polypeptide chains are folded in a
spherical shape.
C. Contains several types of secondary
structure
D. Typical for regulatory proteins

A

a

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

The alpha helix found in myoglobin can
best be described as
A. Primary structure
B. Secondary structure
C. Tertiary structure
D. Motif structure

A

b

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Some parts of a protein that have a specific
chemical structure and function are called
protein
A. chemicals
B. domains
C. subunits
D. enzymes

A

b

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

One of the following is NOT usually a
force that helps to hold the monomer
units of a quaternary protein together?
A. Peptide bonds
B. Disulfide bonds
C. Salt bonds
D. Hydrophobic interactions

A

a

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

If a person breathes into a paper bag, you
would expect their blood CO2 to
A. decrease and their blood pH to increase
B. decrease and their blood pH to decrease
C. increase and their blood pH to increase
D. increase and their blood pH to decrease

A

d

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

The quaternary structure of a protein is
A.the sequence of amino acids in the
polypeptide
B. the coiling or folding of the polypeptide
C. the intertwining of two or more polypeptides
D.the 3-dimensional appearance of the
polypeptide

A

c

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

The action of disrupting the threedimensional shape of a protein is
termed
A. dehydration
B. denaturation
C. deamination
D. hydrolysis

A

b

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

At a pH >pI of a given protein, that protein
becomes ______ , at the pH<pI of that
same protein, it becomes ____ .

A

negatively charged (an anion)
positively charged (a cation)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

The imino acid found in protein structure
(a) Arginine
(b) Proline
(c) Histidine
(d) Lysin

A

b

34
Q

The bonds in protein structure that are
not broken on denaturation.
(a) Hydrogen bonds
(b) Peptide bonds
(c) lonic bond
(d) Disulfide bonds

A

b

35
Q

Which of the following
is not considered a
pyrimidine?
A. C
B. T
C. U
D. G

A

d

36
Q

What type of sugar is
found in the
nucleotides of DNA?
A. deoxyribose
B. ribose
C. glucose
D. none of the above

A

a

37
Q

What is the role of hydrogen bonds in
the structure if DNA?
A. to code for proteins
B. to synthesize proteins
C. to separate the strands
D. to connect the base pairs

A

d

38
Q

Nucleoside is a pyrimidine or
purine base
A.covalently bonded to a
sugar
B.ionically bonded to a sugar
C.hydrogen bonded to a sugar
D.none of the abov

A

a

39
Q

Nucleotide bases and
aromatic amino acids
absorb light respectively at
A.280 and 260 nm
B.260 and 280 nm
C.270 and 280 nm
D.260 and 270 nm

A

b

40
Q

Which of the following is found
on RNA but not DNA?
A.Uracil
B.Deoxyribose
C.Phosphate
D.Adenine

A

a

41
Q

Which is true about the pairing of
bases in the DNA molecule?
A. purines always pair with
pyrimidines
B. a single ring base pairs with
another single ring base
C. a double ring base pairs with
another double ring base
D. purines pair with purines and
pyrimidines with pyrimidines

A

a

42
Q

A messenger acid is 336 nucleotides
long, including the initiator and
termination codons. The maximum
number of amino acids in the
protein translated from this mRNA
is:
A. 999
B. 630
C. 330
D. 111
E. 110

A

d

43
Q

With what mRNA codon would the
tRNA in the diagram be able to
form a codon-anticodon base
pairing interaction?
A. 3’-AUG-5’
B. 3’-GUA-5’
C. 3’-CAU-5’
D. 3’-UAC-5’
E. 3’-UAG-5’

A

a

44
Q

What is the function of enzymes within living systems?
A) structural elements
B) neurotransmitters
C) catalysts
D) hormones

A

c

45
Q

Enzymes have names that

A) always end in -ase
B) always end in -in
C) can end either in -in or -ase
D) can end in either -in or -ogen

A

c

46
Q

The protein portion of a conjugated enzyme is called a(n)

A) apoenzyme.
B) coenzyme.
C) holoenzyme.
D) cofactor.

A

a

47
Q

Which of the following could be a component of a conjugated enzyme?
A) coenzyme
B) cofactor
C) apoenzyme
D) more than one correct response
E) no correct response

A

d

48
Q

Enzyme cofactors that bind covalently at the active site of an enzyme
are referred to as .

(a) cosubstrates.
(b) prosthetic groups.
(c) apoenzymes.
(d) vitamin

A

b

49
Q

Which of the following statements concerning the effect of temperature
change on an enzyme-catalyzed reaction is correct?

A) An increase in temperature can stop the reaction by denaturing
the enzyme.
B)An increase in temperature can increase the reaction rate by
increasing the speed at which molecules move.
C)An increase in temperature to the optimum temperature
maximizes reaction rate.
D) more than one correct response
E) no correct response

A

d

50
Q

A catalyst can promote product formation during a chemical reaction
by .
(a) lowering the activation energy barrier.
(b) stabilizing the transition state.
(c) positioning reactants in the correct orientation.
(d) bringing reactants together.
(e) all of the above

A

e

51
Q

Which of the following is characteristic of an enzyme catalyst?

(a) It positions reactants in the correct orientation.
(b) It lowers the activation energy barrier.
(c) It binds the transition state tighter than the substrate.
(d) all of the above

A

d

52
Q

An enzyme active site is the location in the enzyme where
A) protein side groups are brought together by bending and folding
to form a site for interactions with substrates
B) the catalyst interactions with the enzyme
C) catalyst molecules are generated
D) the substrate creates the catalyst molecules

A

a

53
Q

An enzyme active site is the location in an enzyme where substrate
molecules

A) are generated.
B) become catalysts.
C) undergo change.
D) more than one correct response
E) no correct response

A

c

54
Q

For the enzyme reaction A+ B = C + D, Delta Go
‘ = + 1
kcal/mol. This reaction will proceed spontaneously in a
forward direction if:
A. The concentration of C is increased one-hundred fold
B. The concentration of A is increased one-hundred fold
C. The concentration of B is lowered one-hundred fold
D.The concentration of both A and D are increased onehundred fold

A

b

55
Q

Which of the following statements about enzymes or
their function is true?
A.Enzymes do not alter the overall change in free
energy for a reaction
B. Enzymes are proteins whose three-dimensional form
is key to their function
C.Enzymes speed up reactions by lowering activation
energy
D. All of the above

A

d

56
Q

What is the optimal temperature range
for the majority of enzymes?
A. 40-55 ℃
B. 35-40 ℃
C. 25-30 ℃
D. 15-20 ℃

A

b

57
Q

An allosteric activator
A. increases the binding affinity
B. decreases the binding affinity
C. stabilizes the R state of the protein
D. both (a) and (c)

A

d

58
Q

Reactants of an enzyme-catalyzed
reaction are known as
A. products
B. substrates
C. proteins
D. complex

A

b

59
Q

The location on an enzyme where
binding occurs is known as the
A. action point
B. enzyme
C. binding location
D. active site

A

d

60
Q

Enzymes catalyze reactions by
A.Increasing the free energy of the system so that the
change in free energy is positive
B.Increasing the free energy of the substrate so that it is
greater than the free energy of the product
C. Changing the equilibrium constant for the reaction
D. Decreasing the free energy of activation

A

d

61
Q

An apoenzyme
A. Includes non-protein compounds such as metal ions
B.Consists of complex organic structures which may be
classified as activation-transfer coenzymes or oxidationreduction coenzymes
C.Is the protein portion of the enzyme without the
cofactors
D. None of the above

A

c

62
Q

NAD+, FAD, and FMN are all cofactors
for:
A. Oxidoreductases
B. Transferases
C. Hydrolases
D. Ligases

A

a

63
Q

At the end of a chemical reaction
A. an enzyme’s structure is altered
B.an enzyme is detached from the product,
has its original structure, and can catalyze
more chemical reactions
C.the enzyme loses its ablity to catallyze other
chemical reactions
D.the enzyme remains attached to the
products

A

b

64
Q

Glycolytic pathway regulation involves
A. allosteric stimulation by ADP
B. allosteric inhibition by ATP
C. feedback, or product, inhibition by ATP
D. all of the above

A

d

65
Q

Why does the glycolytic pathway continue in the direction of
glucose catabolism?
A. There are essentially three irreversible reactions that act as the
driving force for the pathway
B. High levels of ATP keep the pathway going in a forward
direction
C. The enzymes of glycolysis only function in one direction
D. Glycolysis occurs in either direction

A

a

66
Q

The released energy obtained by oxidation of glucose is stored as
A. a concentration gradient across a membrane
B. ADP
C. ATP
D. NAD+

A

c

67
Q

For every one molecule of sugar glucose which is oxidized
molecule of pyruvic acid are produced.
A.1
B.2
C.3
D.4

A

b

68
Q

The enzymes of glycolysis in a eukaryotic cell are located in the
A.intermembrane space
B.plasma membrane
C.cytosol
D.mitochondrial matrix

A

c

69
Q

Which of the following is not true of glycolysis?
A. ADP is phosphorylated to ATP via substrate level
phosphorylation
B.The pathway does not require oxygen
C.The pathway oxidizes two moles of NADH to NAD+ for each mole
of glucose that enters
D.The pathway requires two moles of ATP to get started
catabolizing each mole of glucos

A

c

70
Q

ATP is from which general category of molecules?
A.Polysaccharides
B.Proteins
C.Nucleotides
D.Amino acids

A

c

71
Q

Which of the following regulates glycolysis steps?
A.Phosphofructokinase
B.Hexose kinase
C.Pyruvate kinase
D.All of these

A

d

72
Q

Which of the following is not a mechanism for altering the flux of
metabolites through the rate-determining step of a pathway?
A. Allosteric control of the enzyme activity
B. Block active sites
C. Genetic control of the enzyme concentration
D. Covalent modification of the enzyme

A

b

73
Q

Phosphofructokinase, the major flux-controlling enzyme of
glycolysis is allosterically inhibited and activated respectively by
A.ATP and PEP
B.AMP and Pi
C.ATP and ADP
D.Citrate and ATP

A

c

74
Q

Where does glycolysis occur?
A. inner membrane of mitochondria
B. matrix of mitochondria
C. stroma of chloroplast
D. cytoplasm

A

d

75
Q

Sports physiologists wanted to monitor
athletes to determine at what point their
muscles were functioning anaerobically. They
could do this by checking for a buildup of
which of the following compounds?
A. oxygen
B. ATP
C. lactate
D. carbon dioxide

A

c

76
Q

There are four enzymes of gluconeogenesis that
circumvent the irreversible steps in glycolysis. When
starting with the substrate pyruvate or lactate they are
A.Hexokinase, phosphofructokinase-1,
phosphofructokinase-2 and pyruvate kinase
B.Pyruvate carboxylase, phosphoenolpyruvate
carboxykinase, fructose-1,6-bisphosphatase, and
glucose-6-phosphatase
C.Glycerol kinase, glycerol-3-phosphate
dehydrogenase, fructose-2,6-bisphosphatase, and
glucose-6-phosphatase
D.Amino transferase, phosphoenolpyruvate
carboxykinase, fructose-2,6-bisphosphatase, and
glucose-6-phosphatase

A

b

77
Q

The enzymes that remove phosphate groups during the process of gluconeogenesis and circumvent two of the three irreversible reactions of glycolysis are

A. Pyruvate kinase and glycerol kinase
B.Phosphoenolpyruvate carboxykinase and glycerol
kinase
C.3-Phosphoglycerate kinase and fructose-1,6-
bisphosphatase
D.Fructose-1,6-bisphosphatase and glucose-6-
phosphatase

A

d

78
Q

The most important control step in gluconeogenesis is fructose-1,6- bisphosphatase. All of the following statements are true EXCEPT
A.Fructose-1,6-bisphosphatase converts fructose-2,6-bisphosphate to fructose-6-phosphate
B.During times when insulin is high, fructose-1,6-bisphosphatase is inhibited by fructose-2,6-bisphosphate
C.During a fast or exercise when glucagon and/or epinephrine are high, fructose-1,6-bisphosphatase is active because of the absence
of fructose-2,6-bisphosphate
D.Glycolysis or gluconeogenesis cannot be active at the same time. If they were is would be a futile cycle

A

a

79
Q

In the liver, glucagon will activate
A. Glycolysis and glycogen synthesis
B. Gluconeogenesis and glycogenolysis
C. Gluconeogenesis and glycogen synthase
D. Gluconeogenesis and glycogen synthesis

A

b

80
Q

Which of the following statements about hormonal levels during different
states is true?
A.During the time you are eating a high carbohydrate mixed meal, the
insulin to glucagon ratio will decrease
B.When passing from the fed to fasting state, insulin and glucagon usually
decrease
C. When playing basketball, epinephrine is usually low and insulin is high
D.After running for 20 miles, epinephrine and glucagon are high and insulin
is low

A

d

81
Q

All of the following will result in activation of glycogen
phosphorylase in skeletal muscle EXCEPT
A.Increased concentrations of AMP from contraction of muscle
B. Increased epinephrine and cAMP
C. Increased cytosolic [Ca++]
D. Increased protein phosphatase
E. Increased activity of glycogen phosphorylase kinase

A

d

CHELE (17 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions