BioChE Flashcards
(182 cards)
1
Q
Glucose and fructose are examples of
A. double sugars
B. disaccharides
C. single sugars
D. polysaccharides
A
single sugars
2
Q
(CH2O)n is the molecular formula for which type of macromolecules?
A. Proteins
B. Lipids
C. Carbohydrates
D. Nucleic Acid
A
carbohydrates
equal ang C sa H20
Cn(H20)n
3
Q
The ultimate source of energy that sustains living systems is
A. glucose
B. sunlight
C. oxygen
D. carbon dioxide
A
sunlight
4
Q
Which of the following is NOT a polysaccharide?
A. Glycogen
B. Starch
C. Sucrose
D. Cellulose
A
sucrose
disaccharide
glucose + fructose
5
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
carbohydrates
key: quick energy source
6
Q
Sugars, starches, and cellulose belong to which major class of
biological molecules?
A. Nucleic acids
B. carbohydrates
C. lipids
D. polypeptides
A
carbohydrates
7
Q
What would be the molecular formula for a polymer made by linking
ten glucose molecules together by condensation, if the molecular formula
for glucose is C6H12O6?
A. C60H100O50
B. C60H102O51
C. C60H120O60
D. (C6H12O6)10
A
C60H102O51
8
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
starches
polysaccharide that can be absorbed/ processed by the body
9
Q
What does insulin do?
A. inhibit gluconeogenesis and stimulate glycolysis
B. stimulate both gluconeogenesis and glycolysis
C. stimulate gluconeogenesis and inhibit glycolysis
D. inhibit both gluconeogenesis and glycolysis
A
inhibit gluconeogenesis and stimulate glycolysis
insulin is released when sugar is high to make it low
gluconeogenesis - prod of glucose from pyravate & other precursors
glycolysis - consumption of glucose -> pyravates
10
Q
In which of the following cell organelles is it expected to find the
biochemical machinery that harnesses energy from the breakdown of
sugar molecules to synthesize large amount of ATP?
A. lysosome
B. mitochondria
C. vesicles
D. plasma membrane
A
mitochondria
11
Q
Which of the following is not considered a pyrimidine?
A. Cytosine
B. Thymine
C. Guanine
D. Uracil
A
12
Q
Which base is present only in RNA?
A. thymine
B. uracil
C. adenine
D. cytosine
A
13
Q
A nucleotide consists of
A. a sugar, a base, and a phosphate
B. a sugar and a phosphate
C. paired bases
D. a sugar, a base, and three phosphates
A
14
Q
What type of sugar is found in the nucleotides of DNA?
A. deoxyribose
B. ribose
C. glucose
D. none of the above
A
15
Q
What is the role of hydrogen bonds in the structure of DNA?
A. to code for proteins
B. to synthesize proteins
C. to separate the strands
D. to connect the base pairs
A
16
Q
Whose X-ray work aided Watson and Crick in their discovery of the
double helix?
A. W.H. Bragg
B. L. Pauling
C. R. Franklin
D. Leaderberg
A
17
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 above
A
18
Q
The sugar in RNA is ______, the sugar in DNA is ______
A. deoxyribose, ribose
B. ribose, deoxyribose
C. ribose, phosphate
D. ribose, uracil
A
19
Q
In gel electrophoresis, what fragments will move most quickly through
a gel?
A. Large fragments
B. Small fragments
C. Large genome
D. None of these
A
20
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
21
Q
Which of the following is found on RNA but not DNA?
A. Uracil
B. Deoxyribose
C. Phosphate
D. Adenine
A
22
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
23
Q
Which of the following is a secondary structure breaker/alpha helix
terminator?
A. Pro
B. Glu, Leu
C. Phe
D. Cys, Ser
A
24
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
25
Both strands of DNA serve as templates concurrently in?
A. replication
B. excision repair
C. mismatch repair
D. none of these
26
Proofreading activity to maintain the fidelity of DNA synthesis
A. occurs after the synthesis has been completed
B. is a function of the 3' 5' exonuclease activity of the DNA
polymerases
C. requires the presence of an enzyme separate from the DNA
polymerases
D. occurs in prokaryotes but not eukaryotes
27
Which of the following repairs nicked DNA by forming a
phosphodiester bond between adjacent nucleotides?
A. Helicase
B. DNA gyrase
C. Topoisomerases
D. DNA ligase
28
The replication of chromosomes by eukaryotes occurs in a relatively
short period of time because
A. the eukaryotes have more amount of DNA for replication
B. the eukaryotic replication machinery is 1000 times faster than
the prokaryotes
C. each chromosome contains multiple replicons
D. eukaryotic DNA is always single stranded
29
During which of the following process a new copy of a DNA molecule
is precisely synthesized?
A. Transformation
B. Transcription
C. Translation
D. Replication
30
Which of the following enzyme adds complementary bases during
replication?
A. Helicase
B. Synthesase
C. Replicase
D. Polymerase
31
Which of the following enzymes unwind short stretches of DNA helix
immediately ahead of a replication fork?
A. DNA polymerases
B. Helicases
C. Single stranded binding proteins
D. Topoisomerases
32
Which DNA polymerase removes RNA primers in DNA synthesis?
A. Polymerase I
B. Polymerase II
C. Polymerase III
D. none of these
33
DNA replication takes place in which direction?
A. 3’ to 5’
B. randomly
C. variable from organism to organism
D. 5’ to 3’
34
Enzyme, responsible for proofreading base pairing is
A. DNA polymerase
B. Telomerase
C. Primase
D. DNA ligase
35
DNA helicase is used to
A. unwind the double helix
B. interact the double helix closely
C. break a phosphodiester bond in DNA strand
D. none of the above
36
How many bases of nucleic acid determine a single amino acid?
A. one
B. four
C. two
D. three
37
The 5' and 3' numbers are related to the
A. length of the DNA strand
B. carbon number in sugar
C. the number of phosphates
D. the base pair rule
38
What is the main damaging effect of UV radiation on DNA?
A. Depurination
B. Formation of thymine dimers
C. Single strand break
D. Dehydration
39
RNA is synthesized on a DNA template in a process called _____,
which utilizes the enzyme _____.
A. translation, RNA polymerase
B. transcription, DNA polymerase
C. transcription, RNA polymerase
D. replication, DNA polymerase
40
Which of the following enzyme is used for synthesis of RNA under
the direction of DNA?
A. RNA polymerase
B. DNA ligase
C. DNA polymerase
D. RNA ligase
41
Which of the following is a product of transcription?
A. mRNA
B. tRNA
C. rRNA
D. all of these
42
Which of the following RNAs bind to an amino acid?
A. mRNA
B. tRNA
C. snRNA
D. rRNA
43
Recognition/binding site of RNA polymerase is called
A. receptor
B. promoter
C. facilitator
D. terminator
44
An mRNA transcript of a gene contains
A. a start codon
B. a stop codon
C. a terminator
D. all of these
45
Where in the cell is the DNA transcribed into mRNA?
A. Cytoplasm
B. Nucleus
C. Golgi
D. Cell cytoskeleton
46
Since the two strands of the DNA molecule are complementary, for
any given gene:
A. The RNA polymerase can bind to either strand.
B. Only one strand actually carries the genetic code for a particular
gene.
C. Each gene possesses an exact replica so that no mutation
occurs.
D. A gene transcribed in the 5’ to 3’ direction on one strand can be
transcribed in the 3’ to 5’ direction on the other strand.
47
The site of protein synthesis is
A. Ribosome
B. Nucleus
C. Endoplasmic reticulum
D. Chromosome
48
The structure in a bacterium that indicates an active site for protein
synthesis is
A. a chromosome.
B. a cell membrane,
C. a flagellum.
D. a polysome.
49
Which of the following is not necessary for protein synthesis to occur,
once transcription is completed?
A. tRNA
B. Ribosomes
C. mRNA
D. DNA
50
During the process of translation:
A. the peptide is ‘passed’ from the tRNA in the P site to the tRNA
in the A site.
B. incoming tRNAs must first bind to the E site.
C. initiation begins with the binding of the ribosomal SSU to the
poly A tail of the mRNA.
D. the mRNA is translated by one ribosome at a time.
51
The nucleolus of the nucleus is the site where:
A. RNA processing occurs
B. rRNA is transcribed and ribosomal subunits are assembled
C. tRNA are charged with amino acids
D. mRNA is translated into protein
52
The ribosomes are composed of
A. proteins
B. RNA
C. both A and B
D. lipids
53
Which is required for protein synthesis?
A. tRNA
B. mRNA
C. rRNA
D. All of these
54
Initiation of eukaryotic translation begins when the
A. large and small subunits link together, then bind to the mRNA.
B. ribosomal small subunit holding an initiator tRNA binds to the 5’
end of mRNA.
C. ribosome binds to of the start codon and an initiator tRNA enters
the ribosome.
D. initiator tRNA binds to the start codon, followed by binding of
the ribosome large subunit.
55
On the ribosome, mRNA binds
A. between the subunits
B. to the large subunit
C. to the small subunit
D. none of these
56
Ribosomes select the correct tRNAs
A. based on the aminoacyl group
B. solely on the basis of their anticodons
C. depending on their abundance in the cytosol
D. with the least abundant anticodons
57
Which of the following amino acid starts all proteins synthesis?
A. Glycine
B. Proline
C. Thymine
D. Methionine
58
The simplest way to differentiate a prokaryotic cell from a eukaryotic
cell is
A. to look for a plasma membrane
B. to see if a nucleus is present
C. to check for the presence of DNA
D. to determine if the cell is an entire organism or not
59
Which macromolecule does not dissolve in water?
A. proteins
B. lipids
C. carbohydrates
D. nucleic acids
lipids
| non polar and hydrophobic
60
What are the monomers of lipids?
A. Amino acids
B. Simple sugars
C. Fatty acids and glycerol
D. Nucleic acids
fatty acids and glycerol
61
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
enzyme action
62
What type of organic substances are fats?
A. nucleic acid
B. carbohydrate
C. protein
D. lipids
lipids
63
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
saturated
| single bonds lang
64
Which of the following is a polymer?
A. nucleic acid
B. fatty acid
C. Amino acid
D. Glycerol
nucleic acid
| monomers nya are nucleotides
## Footnote
fatty acid is more biomolecule than polymer
65
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
nucleic acid
| key: genetic info
66
Which has the higher melting point: (a) a triglyceride containing only
lauric acid and glycerol or (b) a triglyceride containing only stearic acid and
glycerol?
A. (a)
B. (b)
C. Both have equal melting points
D. None of the above
b
| key: sino may mas higher VDW
VDW directly propor to length of molecule
## Footnote
LA = 12C
SA = 18 C (higher)
67
Hydrolysis of a triglyceride produces
A. many amino acids
B. different types of nucleotides
C. fatty acids and glycerol
D. monosaccharides
fatty acids and glycerol
68
An important function of cholesterol is to:
A. modulate membrane fluidity
B. enhance blood circulation
C. prevent bile salts formation
D. none of these
modulate membrane fluidity
## Footnote
if Temp
is high cholesterol increases the melting point of membrane
If low cholesterol prevents stiffening of cell membrane
69
A fat-soluble vitamin that regulates blood clotting is
A. vitamin A
B. vitamin D
C. vitamin C
D. vitamin K
vitamin K
70
example of aldotrioses
glyceraldehyde
| nag iisa
## Footnote
simplest hydrocarbon
71
Cellular respiration takes place mostly in:
A. chloroplasts
B. ribosomes
C. nucleus
D. mitochondria
mitochondria
72
Where does glycolysis occur?
A. inner membrane of mitochondria
B. matrix of mitochondria
C. stroma of chloroplast
D. cytoplasm
cytoplasm
73
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
all of the above
74
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
There are essentially three irreversible reactions that act as the
driving force for the pathway
| kay irreversible ya reactions nga ga drive siya so no choice but 1D lang
75
The released energy obtained by oxidation of glucose is stored as
A. a concentration gradient across a membrane
B. ADP
C. ATP
D. NAD+
ATP
76
For every one molecule of sugar glucose which is oxidized molecule
of pyruvic acid are produced.
A. 1
B. 2
C. 3
D. 4
2
77
The enzymes of glycolysis in a eukaryotic cell are located in the
A. intermembrane space
B. plasma membrane
C. cytosol
D. mitochondrial matrix
cytosol
| cytoplasm
78
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 glucose
The pathway oxidizes two moles of NADH to NAD for each mole
of glucose that enters
| NAD ---> NADH dat
79
ATP is from which general category of molecules?
A. Polysaccharides
B. Proteins
C. Nucleotides
D. Amino acids
nucleotides
80
Which of the following regulates glycolysis steps?
A. Phosphofructokinase
B. Hexose kinase
C. Pyruvate kinase
D. All of these
all of these
| these are the 3 irrev rxns tung sa glycolythic pathway
81
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
block active sites
82
how to solve for n(water removed)
of glucose - 1
83
carrier of genetic info
Deoxyribonucleic acid
84
intermediate in the expression of genetic info and other diverse roles
Ribonucleic acid
85
describes the flow of genetic info within a biological system
Central dogma
86
devised central dogma
Francis Crick (1957)
87
monomeric units of nucleic acids
nucleotides
| nucleotides =
88
a heterocyclic aromatic org compound consisting of a pyramidine ring fused to an imidazle ring
purine
89
a heterocyclic aromatic org compound similar to benzene and pyridine containing 2 nitrogen atoms at positions 1 and 3 of the sis...
pyramidine
90
ATP meaning
Adenosine triphosphate
91
major energy currency of the cell
ATP
| adenosine triphosphate
92
chemical bond between nucleotide units of different nucleic acids
phosphodiesters
93
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
94
A biological redox reaction always involves
A. an oxidizing agent
B. a gain of electrons
C. a reducing agent
D. all of these
all of these
95
Coenzyme Q is involved in electron transport as
A. directly to O2
B. a water soluble electron donor
C. covalently attached cytochrome cofactor
D. a lipid soluble electron carrier
a lipid soluble electron carrier
| non- polar
96
FAD is reduced to FADH2 during
A. electron transport phosphorylation
B. lactate fermentation
C. Krebs cycle
D. glycolysis
97
During glycolysis, electrons removed from glucose are passed to
A. FAD
B. NAD
C. acetyl CoA
D. pyruvic acid
98
Almost all of the oxygen (O2) one consumes in breathing is converted
to:
A. acetyl CoA.
B. carbon dioxide (CO2)
C. carbon monoxide and then to carbon dioxide
D. water
99
The carbon dioxide is primary a product of
A. Krebs cycle
B. glycolysis
C. electron transport phosphorylation.
D. lactate fermentation.
100
Which of the following is not present during the TCA cycle?
A. NADH
B. O2
C. CO2
D. ATP
101
Which of the following is a list of the stages in the correct order?
A. pyruvate oxidation, glyocolysis, the citric acid cycle, and
oxidative phosphorylation
B. oxidative phosphorylation, glyocolysis, the citric acid cycle, and
pyruvate oxidation
C. glycolysis, pyruvate oxidation, the citric acid cycle, and
oxidative phosphorylation
D. glycolysis, the citric acid cycle, pyruvate oxidation, and
oxidative phosphorylation
102
What are the products of the citric acid cycle?
A. NADH, ATP, FADH2 and CO2
B. O2, ADP, 1 FAD, and NAD+
C. Glucose, ATP, O2 and NADH
D. heat, H2O, NADH, and pyruvate
103
The Krebs Cycle begins when pyruvic acid produced by glycolysis
enters the
A. cytosol
B. air
C. mitochondrion
D. nucleus
104
In aerobic organisms growing in the presence of oxygen, the NADH
produced by glycolysis ultimately donates its high energy electrons to
A. electron transport chains in the mitochondria
B. ATP
C. pyruvate
D. glucose
105
Cellular respiration takes place mostly in:
A. chloroplasts
B. ribosomes
C. nucleus
D. mitochondria
106
The main purpose of the electron transport chain is to:
A. Use high energy electrons from other cycles to convert ADP
into ATP
B. Maintain a stable balance of high energy electrons
C. Constantly distribute electrons throughout the cell
D. Tell the cell when glycolysis should stop or start
107
Oxidative phosphorylation:
A. Is anaerobic
B. Requires AMP
C. Requires the electron transport system
D. Is not dependent upon development of a proton gradient
108
Where are the proteins of the electron transport chain located?
A. cytosol
B. mitochondrial outer membrane
C. mitochondrial inner membrane
D. mitochondrial matrix
109
The ATP synthase responsible for most of the ATP synthesis in the
body is located:
A. On the outer side of the outer mitochondria membrane
B. On the inner side of the outer mitochondria membrane
C. On the outer side of the inner mitochondria membrane
D. On the inner side of the inner mitochondria membrane
110
In the electron transport chain, the final electron acceptor is:
A. oxygen
B. a molecule of carbon dioxide
C. a molecule of water
D. ADP
111
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
112
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
113
Which of the following is NOT a way of producing ATP in humans?
A. Krebs Cycle
B. Alcohol Fermentation
C. Lactic Acid Fermentation
D. Glycolysis
114
Which of the following is an aerobic product of pyruvate catabolic
metabolism?
A. lactate
B. ethanol
C. acetyl CoA
D. glucose
115
The TCA cycle
A. Is found in the cytosol
B. Is controlled by the ADP/ATP ratio and the NADH concentration
C. Is also called the Cori cycle
D. Produces most of the water made in humans
116
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
117
Anemia, hemorrhage, and chronic obstructive pulmonary disease
can all cause metabolic acidosis The best explanation is that the lack of
oxygen causes
A. a decrease in insulin that, in turn, increases anaerobic
glycolysis in the brain
B. a decrease in oxidative phosphorylation so the cells have to rely
upon anaerobic glycolysis
C. a decrease in the removal of CO 2 from the blood. The resulting
decrease in pH causes an increase in glycolysis in most cells
D. an increase in glycolysis in red blood cells
118
All of the following are considered eukaryotes except
A. archaea
B. protozoa
C. fungi
D. humans
119
The common word for bacteria which are spherical in shape is:
A. coccus
B. spirillum
C. bacillus
D. pleomorphic
120
An organism is completely dependent on atmospheric oxygen for
growth. This organism is:
A. osmotolerant
B. a facultative anaerobe
C. an acidophile
D. an obligate aerobe
121
An organism that grows best above 50oC is called:
A. psychrophilic
B. thermophilic
C. none of these
D. mesophilic
122
Food preservation by using salts and sugars works by:
A. raising pH
B. lowering osmotic pressure
C. creating a hypertonic environment
D. creating a hypotonic environment
123
Mucus helps in protecting against pathogens by
A. lowering the pH
B. facilitating the growth of normal flora
C. restricting access to mucosal surfaces
D. sequestering iron
124
The concept of using microbes to help clean up the environment is
called
A. pasteurization
B. bioremediation
C. fermentation
D. sterilization
125
Which of the following microorganisms is used for the production of
citric acid?
A. Lactobacillus bulgaricus
B. Aspergillus niger
C. Saccharomyces cerevisiae
D. Streptococcus lactis
126
Balanced growth is defined as
A. cells in culture maintaining a constant chemical composition
B. balancing the growth while controlling the pH
C. balancing the growth while controlling the temperature
D. balancing the growth while controlling the nutrient composition
127
Starvation proteins or metabolites are produced by a culture during
which of the following phases of the growth cycle?
A. lag phase
B. stationary phase
C. exponential phase
D. death phase
128
The period between inoculation of bacteria in a culture medium and
beginning of multiplication is known as:
A. stationary phase
B. lag phase
C. exponential phase
D. decline phase
129
In a batch-fed reactor configuration, substrate is added:
A. only at the beginning of the fermentation process
B. periodically throughout the fermentation process
C. only at the end of the fermentation process
D. never
130
Immobilized cell reactors for wastewater treatment have the
advantage of having/being:
A. higher cell concentration
B. more stable and preventing washout
C. higher maximum dilution rate
D. all of the above
131
stop codons
UAA/UAG/UGA
132
start codon
Methionine
133
134
2 types of metabolism
catabolism
anabolism
135
building up of molecules
anabolism
136
breaking down of molecules
catabolism
137
these nutrients can be broken down into smaller molecules
carbohydrates >> ___
fats >> ___
proteins >> ___
> glucose
> glycerol and fatty acids
> amino acids
138
release energy from glucose (usually) coupled to ATP synthesis
Celullar respiration
139
an aerobic process that requires O2 and releases CO2
Cellular respiration
140
What are the phases of cellular respiration
Glycolysis
-
-
-
not complete
| all is known as Krebs cycle
141
citric acid cycle
1. C2 acetyl group from prep rxn combines w/ a C4 molelcule to produce C6 citrate
2. Oxidation of citrate by removal of hydrogens
3. Produces 3 NADH and 1 FADH2
4. xx
5. xx
142
series of electron carrier molecules
electron transport chain
143
reverse of glycolysis
gluconeogenesis
144
synthesis of glucose from non-carbohydrate precursors
gluconeogenesis
145
Bioprocess engineering deals with the
A. application of engineering principles to processes using living
cells or their subcomponents
B. application of chemical, mechanical, biological, and industrial
engineering
C. equipment design and manufacturing practices
D. all of the above
all of the above
146
What are the chemical elements that form most of living biological
matter?
A. Carbon
B. Nitrogen
C. Oxygen
D. Hydrogen
E. All of the above
E. All of the above
147
What are described as the "building blocks of Protein"?
A. Fiber
B. Lipids
C. Amino Acids
D. Nutrients
148
Amino acids required in the human diet and not synthesized by the body
are called
A. specialized
B. essential
C. trace
D. accessory
149
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
150
When the amino acid alanine (R group 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
Hint: isoelectric point of alanine is 6.00
151
What is the isoelectric point of glutamic acid? pKa(COOH) = 2.19,
pKa(R) = 4.25, pKa(NH2) = 9.67.
A. 3.22
B. 6.96
C. 5.93
D. 5.37
152
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.
153
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
154
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.
155
Which amino acids would most likely reside in the membrane
anchoring domain of a membrane protein?
A. isoleucine, valine, phenylalanine
B. phenylalanine, valine, aspartate
C. leucine, threonine, lysine
D. lysine, arginine, histidine
156
Which of the following is true of β-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 α-helix
D. All of the above.
157
The primary stabilizing force of protein secondary structure is
A. Ionic bonds
B. Covalent bonds
C. Van der Waals forces
D. Hydrogen bonds
158
Two types of β-pleated sheets can be called:
A. Parallel and antiparallel
B. Left handed and right handed.
C. Φ and Ψ
D. α and β
159
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.
160
The alpha helix found in myoglobin can best be described as
A. Primary structure
B. Secondary structure
C. Tertiary structure
D. Motif structure
161
Some parts of a protein that have a specific chemical structure and
function are called protein
A. chemicals
B. domains
C. subunits
D. enzymes
162
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
163
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
164
Hemoglobin has a quaternary structure and is made up of
A. six polypeptide chains: two 𝛼-chains and four 𝛽-chains
B. two polypeptide chains: one 𝛼-chain and one 𝛽-chains
C. four polypeptide chains: two 𝛼-chains and two 𝛽-chains
D. five polypeptide chains: two 𝛼-chains and three 𝛽-chains
165
The action of disrupting the three-dimensional shape of a protein is
termed
A. dehydration
B. denaturation
C. deamination
D. hydrolysis
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