B2M2 Flashcards
In a genetic code, each codon corresponds to a single amino acid but an amino acid
could also have more than one triplet coding for it. This characteristic is called ____.
A. degenerate
B. comma-less
C. overlapping
D. universality
A. degenerate
A characteristic of the genetic code which shows that the code is read backwards
from a fixed starting point as a continuous sequence of bases, taken three at a time
is referred to as ________.
A. specificity
B. universality
C. redundancy
D. non-overlapping
D. non-overlapping
A characteristic of the genetic code where a specific codon always codes for the
same amino acid?
A. Universality
B. Specificity
C. Redundancy
D. Overlapping
B. Specificity
Which of the following is part of the basic make-up of a nucleotide?
A. Pentose
B. Phosphodiester bond
C. Base pairs
D. Methyl group
A. Pentose
Which of the following statements is true about Chargaff’s rules?
A. The rules apply to both double-stranded DNA and single-stranded RNA nucleic
acids.
B. The amount of A equals the amount of C and the amount of G equals the amount
of T
C. The ratio of base pairs varies among different organisms but is the same in
various tissues of the same organism.
D. The rules, although rigorous, do not influence the stability of the nucleic acid’s
physical configuration.
C. The ratio of base pairs varies among different organisms but is the same in
various tissues of the same organism.
What type of bonds join together a series of nucleotides?
A. non-covalent
B. hydrogen
C. disulfide
D. phosphodiester
D. phosphodiester
Which of the following is the basic unit of heredity that is passed from parents to
offsprings?
A. Allele
B. Gene
C. Phenotype
D. Chromosome
B. Gene
Which of the following term refers to the observable characteristics of an organism?
A. Genotype
B. Exon
C. Phenotype
D. Intron
C. Phenotype
How does an allele differ from a gene?
A. An allele is a specific form of a gene, whereas a gene is the complete sequence
of DNA.
B. A gene is a specific form of an allele, whereas an allele is the complete
sequence of DNA.
C. An allele determines the chromosome type, while genes determine traits.
D. Genes are part of the phenotype, while alleles are part of the genotype.
A. An allele is a specific form of a gene, whereas a gene is the complete sequence
of DNA.
What is the primary function of messenger RNA (mRNA) in the context of vaccines?
A. To directly fight off infections
B. To carry genetic instructions for protein synthesis
C. To replace DNA in cells
D. To create antibodies
B. To carry genetic instructions for protein synthesis
Which viral protein was specifically targeted in the development of mRNA vaccines
for COVID-19?
A. Nucleocapsid protein
B. Envelope protein
C. Spike protein
D. RNA polymerase
C. Spike protein
What is one key safety feature of mRNA vaccines?
A. They contain live attenuated viruses
B. They integrate into the host’s DNA
C. They do not use live virus and cannot alter DNA
D. They cause the disease they are meant to prevent
C. They do not use live virus and cannot alter DNA
The addition of a pentose sugar to a base produces what molecule?
A. Nucleoside
B. Nucleotide
C. Deoxyribonucleoside
D. Ribonucleoside
A. Nucleoside
What is the ribonucleoside of Adenine?
A. Adenosine
B. Guanosine
C. Cytidine
D. Thymidine
A. Adenosine
If a ribose sugar is added to a nucleoside, what is produced?
A. Deoxyribonucleoside
B. Ribonucleoside
C. Nucleoside
D. Nucleotide
B. Ribonucleoside
Which statement BEST describes the central dogma of molecular genetics?
A. RNA remains in the nucleus to transcribe DNA
B. DNA is translated into a protein by a ribosome
C. DNA is transcribed into RNA then RNA is translated into protein
D. The passing of genetic information from RNA to protein by transcription
C. DNA is transcribed into RNA then RNA is translated into protein
Pyrimidine nucleoside hydrolysis would yield which of the following end products?
A. Ribose
B. Adenine
C. Guanine
D. Uracil
D. Uracil
The central dogma of molecular genetics states that all life processes its genetic
information in what order?
A. Transcription of DNA to RNA, Translation of RNA to Proteins
B. Transcription of RNA to DNA, Translation of DNA to Proteins
C. Translation of Proteins to RNA, Transcription of DNA back to Proteins
D. Proteins can be transcribed to RNA or DNA and vice versa
A. Transcription of DNA to RNA, Translation of RNA to Proteins
The structural core of a nucleosome is composed of:
A. 2 molecules each of h2a, h2b, h3, h4 histones
B. 1 molecule each of h2a, h2b, h3, h4 histones
C. 2 molecules each of h1, h2a, h3, h4 histones
D. 1 molecule each of h1, h2a, h2b, h3 histones
A. 2 molecules each of h2a, h2b, h3, h4 histones
Which of the following histone is not found in a nucleosome?
A. h1
B. h2a
C. h3
D. h4
A. h1
Genes are encoded in how many percent of the total human DNA?
A. 5%
B. 10-15%
C. 25%
D. 40-50%
B. 10-15%
Which of the following best describes a phenotype?
A. The genetic makeup of an organism
B. The observable physical or biochemical characteristics of an organism
C. The specific location of a gene on a chromosome
D. A variant form of a gene
B. The observable physical or biochemical characteristics of an organism
Which of the following best describes a genotype?
A. The physical expression of trait is an organism
B. The combination of alleles that an organism possesses
C. The environmental factors affecting an organism’s traits
D. The process by which traits are passed from parents to offspring
B. The combination of alleles that an organism possesses
Garry, a level 1 medical student was tasked to discuss on Alleles. Which of the
following would best define alleles?
A. It refers to different genes that exist at a specific locus.
B. It is the total genetic information of an organism.
C. It pertains to the process of cell division.
D. It is the observable traits of an organism
A. It refers to different genes that exist at a specific locus.
Which of the following best explains the role of phosphodiester bonds in the
structure of DNA?
A. They connect nucleotides through hydrogen bonds between complementary
bases
B. They create a rigid structure that prevents DNA from unwinding
C. They link the 5’ hydroxyl group of one nucleotide to the 3’ hydroxyl group of
another
D. They facilitate the addition of mononucleotides to the DNA strand
C. They link the 5’ hydroxyl group of one nucleotide to the 3’ hydroxyl group of
another
What type of bonds hold the base pairs together in DNA?
A. Hydrogen bonds
B. Ionic bonds
C. Covalent bonds
D. Phosphodiester bonds
A. Hydrogen bonds
What type of bond connects the nucleotides in a DNA strand?
A. Hydrogen bonds
B. Ionic bonds
C. Covalent bonds
D. Phosphodiester bonds
D. Phosphodiester bonds
What are the major purine derivatives?
A. Adenine and Guanine
B. Adenine and Uracil
C. Guanine and Uracil
D. Guanine and Cytosine
A. Adenine and Guanine
What are phosphate esters of a nucleoside?
A. Nucleic acid
B. Nucleoside
C. Nucleotide
D. Mononucleoside
C. Nucleotide
What is an example of a nucleotide?
A. Uridine
B. Thymidylate
C. Deoxycytidine
D. Cytidine
B. Thymidylate
The duplication of DNA, giving rise to a new DNA molecule with the same base
sequence as the original, is known as:
A. Deletion
B. Replication
C. Transcription
D. Translation
B. Replication
Which of the following is true about the central dogma of molecular genetics?
A. Protein -> RNA -> DNA
B. DNA -> RNA -> Protein
C. RNA -> DNA -> Protein
D. Protein -> DNA -> RNA
B. DNA -> RNA -> Protein
Among the three major types of RNA that participate in the process of protein
synthesis, which of the following comprises only about 5% of the RNA in the cell yet
is by far the most heterogenous type of RNA in terms of size?
A. mRNA
B. tRNA
C. rRNA
D. sRNA
A. mRNA
Consumption of high amounts of beef, liver, and anchovies in the diet are
predisposing factors to Gout flare due to increased production of uric acid catalyzed
by what enzyme?
A. 5-monophosphate kinase of the intestinal mucosa
B. Xanthine oxidase of the intestinal mucosa
C. Adenosine Deaminase of the intestinal mucosa
D. PRPP synthetase in the intestinal mucosa
B. Xanthine oxidase of the intestinal mucosa
Which among the following compounds is excreted when there is competitive
inhibition of xanthine oxidase?
A. Para-aminobenzoic acid
B. Thymine
C. Xanthine
D. Guanosine
C. Xanthine
Which of the following is correct regarding consumption of nucleic acids in the diet?
A. Nucleosides are converted to nucleotides via nucleotidases
B. Most mononucleotides are synthesized via De Novo Biosynthesis
C. Phosphate and sugars produced by the digestion of nucleic acids cannot be
reutilized.
D. Purine or pyrimidine sources are essential components of the diet
B. Most mononucleotides are synthesized via De Novo Biosynthesis
This is referred to as the initial step in De novo purine biosynthesis:
A. Glumatine Phosphoribosyl Amidotransferase catalyzes the conversion of PRPP
to 5-Phosphoribosylamine
B. Ribose-5-Phosphate is converted in to 5-Phosphoribosyl-1-Pyrophosphate
C. PRPP synthetase catalyzes the conversion of PRPP to Ribose-5-phosphate
D. 5-Phosphoribosylamine is converted into PRPP
B. Ribose-5-Phosphate is converted in to 5-Phosphoribosyl-1-Pyrophosphate
In the salvage pathway of purines, what enzyme catalyzes the combination of purine
bases with PRPP to form IMP and GMP?
A. Hypoxanthine guanine phosphoribosyltransferase
B. Amidophosphoribosyltransferase
C. AMP deaminase
D. PRPP Synthetase
A. Hypoxanthine guanine phosphoribosyltransferase
This is referred to as the committed step in De novo purine biosynthesis:
A. Glutamine Phosphoribosyl Amidotransferase catalyzes the conversion of PRPP
to 5-Phosphoribosylamine
B. Ribose-5-Phosphate is converted in to 5-Phosphoribosyl-1-Pyrophosphate
C. PRPP synthetase catalyzes the conversion of PRPP to Ribose-5-phosphate
D. 5-Phosphoribosylamine is converted into PRPP
A. Glutamine Phosphoribosyl Amidotransferase catalyzes the conversion of PRPP
Dietary nucleic acids are digested into mononucleotides by this enzyme:
A. Xanthine oxidase
B. PRPP synthase
C. Pancreatic ribonuclease
D. Adenylosuccinase
C. Pancreatic ribonuclease
Pyrimidine nucleosides undergo which process in order to yield deoxyribose and
pyrimidine end products?
A. Phosphorolysis
B. Hydrolysis
C. Deamination
D. Transamination
B. Hydrolysis
Purine nucleosides undergo phosphorolysis to yield purines and:
A. D-ribose 1-phosphate
B. D-deoxyribose 1-phospohate
C. Glucose 6-phosphate
D. Deoxyribose 6-phosphate
A. D-ribose 1-phosphate
Which of the following participates in diverse cellular functions, including intracellular
energy metabolism, cell signaling pathways, and intercellular communication?
A. DNA
B. Purines
C. Nucleic acid
D. Chromosome
B. Purines
What enzyme is responsible for converting dietary nucleic acids into
mononucleotides?
A. Nucleosidases
B. Mononucleotidases
C. Xanthine oxidase
D. Ribonuclease
D. Ribonuclease
Strict restriction of purine intake reduces the mean serum urate by about which
level?
A. 1 mg/dL
B. 5 mg/dL
C. 10 mg/dL
D. 15 mg/dL
A. 1 mg/dL
In De Novo Purine Biosynthesis, hydrolysis of which molecule is required to drive
several reactions in the pathway?
A. GTP
B. AMP
C. ATP
D. IMP
C. ATP
Which of the following is the first ribonucleotide to be formed in the de novo
pathway?
A. GTP
B. AMP
C. ATP
D. IMP
D. IMP
Enzymes that are involved in the synthesis of purine nucleotides are found in which
part of the cell?
A. Mitochondria
B. Nucleolus
C. Nucleus
D. Cytosol
D. Cytosol
Purines are converted to uric acid by which enzyme?
A. Xanthine oxidase
B. PRPP synthase
C. Pancreatic ribonuclease
D. Adenylosuccinase
A. Xanthine oxidase
Pyrimidine nucleosides are hydrolyzed to pyrimidines through the action of which
enzyme?
A. Pyrimidine nuclease
B. Pyrimidine nucleosidase
C. Pyrimidine hydroxylase
D. Pyrimidine phosphatase
B. Pyrimidine nucleosidase
