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WorksheetsMODULE 2 PINK PACOP BIOCHEM 1-100
Total questions: 100
Worksheet time: 50mins
Name
Class
Date
1.
This region in the nucleus is the site of ribosome assembly.
a)
nuclear membrane
b)
nucleolus
c)
chromatin
d)
chromosome
2.
Which of the following cellular structures is unique in eukaryotes.
a)
Plasma membrane
b)
internal cellular membrane
c)
Ribosomes
d)
Golgi apparatus
3.
These organelles consist of membranous sacs containing powerful oxidase enzyme, and they use molecular oxygen (O2) to detoxify harmful substances.
a)
Lysosomes
b)
peroxisomes
c)
Golgi apparatus
d)
mitochondria
4.
The cellular particles are often referred by their sedimentation coefficient value, for example, 70s ribosome that is expressed in terms of 10 seconds. The abbreviation stands for
a)
Subunit
b)
seconds
c)
Svedberg
d)
none of the above
5.
These are organelles that contain the enzymes for pyruvate oxidation, citric acid cycle, beta oxidation of fatty acids, oxidative phosphorylation and ETC.
a)
Golgi apparatus
b)
nucleus
c)
Lysosomes
d)
mitochondria
6.
Which of the following is / are true?
a)
The endoplasmic reticulum is a system of fluid filled cisterns.
b)
The smooth endoplasmic reticulum is responsible for protein synthesis
c)
The rough endoplasmic reticulum is the site of lipid synthesis
d)
All of the above
7.
Some organelles are specific to plants or animal cells. Which of the following organelles are present in plant cells only? I. Vacuole II. Nuclear envelope III. Cell wall IV. Lysosomes
a)
I only
b)
II and IV
c)
I and II
d)
I and IV
8.
Viruses are not cellular, but are rather termed as” biological entities”. The main reason why viruses are considered a cellular entities is because
a)
A virus contain only one type of nucleic acid, either DNA or RNA.
b)
A virus is very small compared to bacteria
c)
A virus is pathogenic
d)
Scientist cannot classify viruses under the 5 kingdoms of Whittaker
9.
____________ are small, extra chromosomal circular DNA molecules found in prokaryotes.
a)
Nucleoli
b)
plasmids
c)
Genes
d)
histones
10.
Which of the following statements is/ are correct regarding plasmids. I. Plasmids are either DNA or RNA molecules II. Plamids are found in many types of bacteria III. Plasmids replicate independently of the main chromosome IV. Each cell contains only a single copy of plasmids
a)
III only
b)
I and III
c)
II and III
d)
II and IV
11.
The diversity of the different cell types among various organisms lies in their chemical nature. Which of the following pairs is/are accurate?
a)
Bacterial cell membrane- peptidoglycan
b)
Plant cell wall- cellulose
c)
Animal cell membrane-nucleic acid
d)
None of the above
12.
Which of the following is/are true of prions?
a)
A prion is an infectious agent that contains both proteins and nucleic acid
b)
The disease bovine spongiform encephalopathy or mad cow disease is one disease attributed to prions.
c)
Both statement are correct
d)
Both statements are false.
13.
Which of the following structures is/are present in the nucleus?
a)
nuclear membrane
b)
Chromatin
c)
all of the above
d)
A and B only
14.
Which of the following is an active process?
a)
Transport of molecules through protein pores.
b)
Trans membrane transport through protein pores
c)
Both A and B
d)
None of the above
15.
Which of the following statements differentiate simple passive diffusion from facilitated diffusion?
a)
Facilitated diffusion is an active process
b)
Facilitated diffusion is saturable , simple passive diffusion is not
c)
Both statements are correct
16.
Which of the following is affected by digitalis glycosides and ouabain?
a)
Sodium-glucose transport system
b)
CA -Na exchanger
c)
Na-K pump
d)
All of the above
17.
Which of the following iron is co transported with glucose in the small intestine?
a)
Potassium
b)
Sodium
c)
Calcium
d)
Magnesium
18.
The nature of the cell wall of the bacteria is used in their classification. Which of the following is cross-linked, multi layered polysaccharide- peptide complex used as the basis of gram staining.
a)
Peptidoglycan
b)
Teichoic acid
c)
Ergo sterol
d)
Phospholipids
19.
Which of the following is not a biopolymer?
a)
Nucleic acids
b)
Carbohydrates
c)
Amino acids
d)
Lipids
20.
Which of the following statements is/ are correct.
a)
Adenine is nucleoside
b)
Adenosine is a nucleotide
c)
Nucleotides are also known as nucleosides phosphates
d)
All of the above
21.
Which of the following is/ are found in the cytoplasm?
a)
Cytosol
b)
Inclusions
c)
Mitochondrion
d)
All of the above
e)
A and B only
22.
Which of the following is a nucleoside?
a)
Guanine
b)
Guano sine
c)
guano sine monophosphate
d)
Any of the above
23.
Which carbon in the sugar is responsible for the difference between the two nucleic acids?
a)
Carbon-1
b)
Carbon-2
c)
Carbon-3
d)
None of the above
24.
Which of the following statements is/are true regarding nucleic acid primary structure?
a)
DNA contains thymine, while RNA contains uracil
b)
Adenine and guanine are pyridines
c)
Uracil is purine
d)
All of the above
e)
Only A and B
25.
The ribosome in RNA is converted to deoxyribose in DNA by replacing the in RNA with.
a)
Hydroxyl group, hydrogen
b)
Hydrogen, hydroxyl group
c)
Oxygen, hydroxyl group
d)
Hydroxyl group, oxygen
26.
What is wobble?
a)
The ability of certain anticodons to pair with codons that differ at the third base
b)
An error in translation induced by streptomycin
c)
A mechanism that allows for a peptide extension in the 50s subunits of the ribosome
d)
Thermal motions leading to local denaturation of the double DNA double helix
27.
What type of bod connects successive monomer units through a phosphate residue attached to hydroxyl ion on the 5 carbon of one unit with the 3 hydroxyl of the next?
a)
Hydrogen bond
b)
Covalent bond
c)
Phosphodiester bond
d)
None of the above
28.
Which of the following groups is responsible for the acidic character of nucleic acids?
a)
Phosphate group
b)
Nucleotides
c)
Both A and B
d)
None of the above, nucleic acid is a misnomer. Nucleic acids are not acidic
29.
Which of the following are purine bases?
a)
Adenine and Thymine
b)
Adenine and guanine
c)
Cytosine and thymine
d)
Cytosine and uracil
30.
Which of the following nitrogenous bases is present only in DNA?
a)
Adenine
b)
Thymine
c)
Cytosine
d)
Uracil
31.
Which of the following base pairs is boned by a double bond?
a)
Adenine and thymine
b)
Cytosine and guanine
c)
Adenine and guanine
d)
Cytosine and thymine
32.
How many hydrogen bonds are formed between cytosine and guanine?
a)
One
b)
Two
c)
Three
d)
No hydrogen bonds are found between them
33.
The DNA structure is a double helix containing chains which are complementary. Which of the following statements best describes complementary?
a)
In the chains, each end of the helix contains 5 of one strand and the 3 end of the other
b)
Adenine binds to thymine, and cytosine binds to guanine
c)
Several codons may code for the same amino acid
d)
All of the above
34.
Each end of the DNA double helix contains the 5 ends of one strand and the 3 end of the other stand, this statement describes what characteristic of the DNA structures?
a)
Complementary
b)
Antiparallel
c)
Semiconservative replications
d)
Base pairing
35.
What do you call the bond between the 1 carbon of the sugar and the base nitrogen?
a)
Hydrogen bond
b)
Covalent bond
c)
Phosphodiester bond
d)
Glycosidic bond
36.
Which of the following statements is correct?
a)
Some nucleic acid bases are capable of tautomerization
b)
All enzymes are proteins
c)
Both statements A and B
d)
Both statements are incorrect.
37.
Which of the following statements best describes pyrimidine bases?
a)
They have a 5- membered membrane structure
b)
They have a 6 membered membrane structure
c)
Adenine and guanine are pyrimidine bases
d)
Some examples include caffeine, theophylline and theobromine
38.
The primary difference between nucleoside and nucleotides is the presence of phosphate group in the former , this statement is;
a)
true
b)
false
39.
Which of the following best describes the degeneracy of the genetic code?
a)
1 codon =1 amino acid
b)
1 codon =6 amino acid
c)
6 codon=1 amino acid
d)
None of the above
40.
Deoxyribonucleic acid is a double stranded polynucleotide. The base content of DNA displays three sets of equivalent pairs. Which of the following equations are true? 1 .A=T 2. C=G 3. A+ G= T+ C 4. A+ G is not always equal to T+ C
a)
3 only
b)
1 and 2
c)
1, 2 and 3
d)
1, 2 and 4
41.
Which of the following is the most form of DNA?
a)
A-DNA
b)
B-DNA
c)
Z-DNA
d)
All of the following occur in the same frequency in nature
42.
When the two strands of the DNA double helix are separated, each strand can serve as a template for the replication of the new complementary strand. This describes
a)
DNA replication
b)
Transcription
c)
Complementary of base pairing
d)
Semiconservative replication
43.
Which of the following is correct according to Watson –crick model for DNA? 1. DNA consist of a two strands 2. Pairing is A- T and G-C 3. The primary structure of nucleic acids is composed of a double helix stabilized by H- bonds. 4. The chains were complementary and parallel
a)
3 only
b)
1 and 2
c)
1, 2 and 3
d)
1, 2 and 4
44.
The following base pairs form a minor groove?
a)
Cytosine –guanine
b)
Adenine- thymine
c)
Adenine-uracil
d)
A and B only
45.
These are discontinuous stretches in which lagging strand is initially synthesized during DN A replication.
a)
Enhancer
b)
Operon
c)
Okazaki fragments
d)
Primer
46.
A short piece of nucleic acid (DNA or RNA), base paired with a DNA template strand and provide free 3- OH end from which DNA polymerase can extend a DNA strand.
a)
Enhancer
b)
Operon
c)
Okazaki fragments
d)
Primer
47.
DNA polymerase type has a 5’ to 3’ polymerase and 3’ to 5’ proofreading exonuclease activity.
a)
I
b)
II
c)
III
d)
IV
48.
This DNA polymerase I s primarily involved in repairing DNA.
a)
DNA polymerase I
b)
DNA polymerase II
c)
DNA polymerase III
d)
DNA polymerase IV
49.
Which of the following statements is/ are true regarding the secondary structure of nucleic acids?
a)
Guanine forms base pairs with adenine via 2 hydrogen bonds
b)
The B form of the DNA is the most common in biological systems
c)
The breaking of H-bonds caused by high temperature is called melting
d)
A and B
e)
B and C
50.
What is the sequence of the major events in DNA replication? 1. DNA ligase joins fragments of the lagging strands, creating a single DNA molecule. 2. DNA polymerase at the replication fork synthesize DNA in 5’ to 3’ direction. There are two strands, the leading and the lagging strands. 3. DNA double helix is opened by helicases 4. primase creates a temporary RNA 5. DNA polymerase removes RNA primer and fills the gaps between the Okazaki fragments.
a)
1-3-5-4-2
b)
3-4-2-5-1
c)
1-2-5-4-3
d)
4-3-2-5-1
51.
This is a rare human disorder, which progresses to photosensitivity, caused by an inherited excinuclease deficiency.
a)
Xeroderma pigmentosa
b)
Bloom’s syndrome
c)
Fanconi’s anemia
d)
Hodgkin’s lymphoma
52.
Alkylating agents are used in the treatment of Hodgkin’s disease and leukemia’s. Their main mechanism of action is to alkylate this nitrogenous base.
a)
Adenine
b)
Cytosine
c)
Guanine
d)
Thymine
53.
These chemotherapeutic agent binds to bacterial RNA polymerase
a)
Pyrazinamide
b)
Actinomycin
c)
Bleomycin
d)
Rifampicin
54.
Which of the following is/ are true?
a)
RNA polymerase, unlike DNA polymerase does not require primer
b)
DNA polymerase is a nuclease
c)
RNA polymerase is a nuclease
d)
All of the above
e)
Only A and B are correct
55.
Which of the following is a codon of methionine?
a)
UAG
b)
AUG
c)
UGA
d)
UAA
56.
This DNA mutations occur when a purine preplaces a pyrimidine or vice versa.
a)
Transitional
b)
Transversional
c)
Insertion
d)
Frame shift
57.
The purine replaces another purine in mutations.
a)
Transitional
b)
Transversional
c)
Insertion
d)
Frame shift
58.
Which of the following is /are mutations?
a)
Insertion
b)
Deletion
c)
Transition
d)
All of the above
e)
Only A and B
59.
This mutagenic substance is obtained from smoking cigarettes. It intercalates with DNA and causes frame shifts.
a)
Tar
b)
Nicotine
c)
Coal
d)
Benzopyrine
60.
This refers to the noncoding regions that alternate with coding regions in the polypeptide sequence.
a)
Exons
b)
Promoters
c)
Introns
d)
Repressor
61.
This DNA duplex has a special left handed- helical structure.
a)
A-DNA
b)
B-DNA
c)
Z-DNA
d)
F-DNA
62.
Which of the following best describes the mechanism of action of Dactinomycin ( actinomycin D )
a)
Bind to bacterial DNA polymerase
b)
Binds to 30s subunits
c)
Binds to 50s subunits
d)
Intercalates with the minor groove of the double helix
63.
2- aminopyrine is no longer used clinically. It has been found to replace adenine (6-aminopurine) or guanine in DNA resulting to bone marrow toxicity, 2 Aminopyrine exhibit what type of mutation?
a)
Transitional
b)
Transversional
c)
Frameshift
d)
deletion
64.
Which of the following is /are true regarding the central dogma of molecular biology?
a)
Transcription in the synthesis of RNA and DNA
b)
The process of replication produces new RNA
c)
Reverse transcription is impossible
d)
All of the above
65.
Actinomycin D, an antineoplastic drug intercalates between two GC pairs in DNA. Which of the following processes does it inhibits?
a)
Translation
b)
Transcription
c)
DNA repair
d)
Replication
66.
Tumor producing RNA viruses synthesize DNA from RNA in the process called .
a)
Transcription
b)
Reverse transcription
c)
DNA repair
d)
Replication
67.
This enzyme is responsible for removing the RNA primer on DNA.
a)
Excinuclease
b)
DNA ligase
c)
RNA polymerase
d)
DNA polymerase
68.
Which of the following pairs is an accurate pairing of the organism and its start codon?
a)
Eukaryote- formylmethionine
b)
Prokaryote- methionine
c)
Eukaryote- methionine
d)
None of the above
69.
Human catabolize purine to
a)
Urea
b)
Uric acid
c)
Allantoin
d)
Both B and C
70.
This refers to the set of prokaryotic structural genes, which are transcribed as a unit, along with regulatory elements controlling their expression.
a)
Operon
b)
Operator
c)
Inducer
d)
Repressor
71.
When the serum urate levels exceed to solubility limit, the crystals of sodium urate accumulate in soft tissue and joints and causes an inflammatory reaction known as
a)
Lesch nyhan syndrome
b)
Osteomalacia
c)
Gouty arthritis
d)
Von Gierke’s disease
72.
Which of the following statements about amino acid is true?
a)
Acidic Amino acid bear a positive charge at pH 7.0
b)
All amino acid have a chiral carbon
c)
Lysine and arginine are basic amino acids
d)
All of the above
73.
This type of mutation occurs when the codon containing the changed base may become a termination codon
a)
Nonsense mutation
b)
Missence mutation
c)
Silent mutation
d)
Transitional mutation
74.
The result of a point mutation that occurs when UCA (coding for serine ) is converted to UCU ( also coding for serine ) is called
a)
Nonsense mutation
b)
Missense mutation
c)
Silent mutation
d)
Any of the above
75.
Glutamine and asparagine amino acids are
a)
Acidic
b)
Basic
c)
Neutral
d)
Non polar
76.
Which Statement is true?
a)
Cysteine is dimer of cysteine
b)
Cysteine is more stable then cysteine
c)
Both statements are correct
d)
Bothe statement are false
77.
Which of the following amino acids contains basic side chain?
a)
Histidine
b)
Arginine
c)
Leucine
d)
All of the above
e)
Only A and B
78.
Which of the following amino acids contain side chains with sulfur atom?
a)
Methionine
b)
Cysteine
c)
Both A and B
d)
Neither A or B
79.
Which of the following amino acids is responsible for disrupting the alpha helix because its amino group is not geometrically compatible with the right handed spiral alpha helix?
a)
Proline
b)
Valine
c)
Leucine
d)
Glycine
80.
Which of the following amino acids has an imino group?
a)
Phenylalanine
b)
Proline
c)
Tyrosine
d)
Threonine
81.
Which of the following amino acids possesses a hydroxyl group, which renders it them polar?
a)
Serine
b)
Threonine
c)
Tyrosine
d)
Only A and B
e)
All of the above
82.
What stabilizes the primary structure of proteins?
a)
Salt bridges
b)
Hydrophobic bonds
c)
Disulfide bonds
d)
All of the above
83.
Which of the following amino acids possesses a phenolic hydroxyl group?
a)
Serine
b)
Threonine
c)
Tyrosine
d)
Only A and B
e)
All of the above
84.
The isoelectric pH is the pH between pK values on either side of the isoelectric process. Which of the following equation gives an accurate estimate of isoelectric pH.
a)
pI= pK1 =pK2
b)
pI= (pK1+pK2 )/2
c)
pI=(pK1+ pK2 ) 2
d)
pI =pK1> pK2
85.
Using the equation of pI, calculate the pI( isoelectric pH) of alanine pK1 (R-COOH ) = 2.35, p K2 (R-NH3 ) = 9.69
a)
6.02
b)
12.04
c)
24.08
d)
5
86.
Thyroxine, which is chemically 3, 5 3, 5 tetraidothyronine, is used as a precursor of thyroid hormones. What type of biopolymer is thyroxine?
a)
Carbohydrate
b)
Lipid
c)
Protein
d)
Nucleic acid
87.
Peptide bond, a type of amide bond, binds the amino terminal of one amino acid to the carboxyl end of another. What type of process involved in the formation of peptide bonds?
a)
Oxidation
b)
Hydration
c)
Reduction
d)
Dehydration
88.
Which of the following statement is correct?
a)
The C-N bond in the peptide linkage has a partial double bond property that makes it rigid.
b)
Neither the C=O nor the N-H in the peptide bond can dissociate
c)
Each amino acid in the polypeptide chain is called a residue
d)
All of the above
89.
This structure of peptide refers to the order of amino acids in the polypeptide chains and the location of the disulfide bond.
a)
Primary
b)
Secondary
c)
Tertiary
d)
Quaternary
90.
This refers to the spatial arrangements of amino acids residues close to one another in the linear sequence of a polypeptide chain.
a)
Primary
b)
Secondary
c)
Tertiary
d)
Quaternary
91.
18. The overall arrangement and interrelationship of various regions in domains, and individual amino acid residues of the single polypeptide chain is
a)
Primary
b)
Secondary
c)
Tertiary
d)
Quaternary
92.
Alpha helix and b-pleated sheets belong to what structure?
a)
Primary
b)
Secondary
c)
Tertiary
d)
Quaternary
93.
Random coils and triple helices are example to what protein structure?
a)
Primary
b)
Secondary
c)
Tertiary
d)
Quaternary
94.
Fibrous and globular proteins belong to what protein structure?
a)
Primary
b)
Secondary
c)
Tertiary
d)
Quaternary
95.
The arrangement of polypeptide chains in relation to one another in a multi-chained protein refers to what structure?
a)
Primary
b)
Secondary
c)
Tertiary
d)
Quaternary
96.
What do you call the principal method for determining the primary structure of polypeptides? For its initial step, it utilizes phenylisocyanate, which combines with the terminal amino acid of polypeptide.
a)
Grignard
b)
Edman
c)
Molisch
d)
Zollinger
97.
Which ofd the following bonds are found in the quaternary structure of polypeptides? 1. Hydrogen bonds 2. Electrostatic bonds 3. Hydrophobic bonds 4. Covalent bonds
a)
3 only
b)
1 only
c)
44199
d)
All of the above
98.
Denaturation is randomization of the conformation of polypeptide chain. Chemical agents like strong acids or bases, heat, ionic detergents, etc. are involved in the process. Which of the following structures remain unaffected with denaturation? 1. Primary 2. Secondary 3. Tertiary 4. Quaternary
a)
1 only
b)
1 and 2
c)
1 and 3
d)
44200
99.
Which of the following statements is true?
a)
Fibrous proteins are water insoluble
b)
Globular proteins are water soluble
c)
Proteins lose their biologic activity after denaturation
d)
Denaturation of protein are sometimes reversible
e)
All of the above
100.
Which of the following is/are example of essential amino acids?
a)
Tyrosine
b)
Threonine
c)
Tryptophan
d)
Both A and B
e)
Both B and C
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