MCQ Bank

The question's provided answer indicates five ribonucleotides. RNA commonly contains the four standard ribonucleotides—adenine, guanine, cytosine, and uracil—along with modified ribonucleotides in some biological contexts.

MB502T Mid Term Verified

Q82

____ are exceptionally simple and extremely small microorganisms.____

A) viruses
B)
C)
D)

AI Explanation

Viruses are exceptionally simple and extremely small infectious agents. They consist primarily of nucleic acid surrounded by a protein coat and depend on host cells for replication.

MB502T Mid Term Verified

Q83

Simplest amino acid residues ____

A) glycine
B)
C)
D)

AI Explanation

Glycine is the simplest amino acid because its side chain is only a hydrogen atom. Its small size also gives proteins considerable conformational flexibility at glycine residues.

MB502T Mid Term Verified

Q84

First discovered enzyme___

A) Diastase
B)
C)
D)

AI Explanation

Diastase is recognized as the first enzyme to be discovered. It was identified by Anselme Payen and Jean-François Persoz in 1833 while studying starch degradation.

MB502T Mid Term Verified

Q85

Transition mutation example____

A) Alkylation Damage to DNA
B)
C)
D)

AI Explanation

Alkylation damage can alter bases and cause mispairing during DNA replication, producing transition mutations. A transition is a substitution in which a purine replaces another purine or a pyrimidine replaces another pyrimidine.

MB502T Mid Term Verified

Q86

Rosalind Franklin & Maurice wilkins discovered DNA by _____

A) X-ray diffraction
B)
C)
D)

AI Explanation

Rosalind Franklin and Maurice Wilkins used X-ray diffraction techniques to study the structure of DNA. Their diffraction images provided crucial evidence for DNA's helical structure.

MB502T Mid Term Verified

Q87

Types of nucleotides___

A) 5
B)
C)
D)

AI Explanation

There are five major types of nucleotides when considering the standard nitrogenous bases found in nucleic acids: adenine, guanine, cytosine, thymine, and uracil. DNA uses four of these, while RNA uses uracil instead of thymine.

MB502T Mid Term Verified

Q88

How many types of ribonucleic acids are present in body___

A) three
B)
C)
D)

AI Explanation

The three major types of RNA found in cells are messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA). Each has a distinct role in gene expression and protein synthesis.

MB502T Mid Term Verified

Q89

Which RNA contain anticodon___

A) tRNA
B)
C)
D)

AI Explanation

Transfer RNA (tRNA) contains an anticodon sequence that base-pairs with the complementary codon on mRNA. This allows the correct amino acid to be incorporated during protein synthesis.

MB502T Mid Term Verified

Q90

POL IV and POL V are present in plants where they transcribe ____

A) small interference RNAs (RNi)
B)
C)
D)

AI Explanation

Plant DNA polymerases IV and V are involved in transcriptional processes associated with RNA-directed silencing. They participate in pathways producing small interfering RNAs and regulating gene expression.

MB502T Mid Term Verified

Q91

Which strand replicates in forward direction ___

A) leading strand
B)
C)
D)

AI Explanation

The leading strand is synthesized continuously in the same overall direction as the movement of the replication fork. DNA polymerase extends the new strand in the 5′ to 3′ direction.

MB502T Mid Term Verified

Q92

CPD photolyase is present in a variety of organisms except ___

A) human and other placental mammals
B)
C)
D)

AI Explanation

CPD photolyase repairs cyclobutane pyrimidine dimers using light energy. This enzyme is absent in humans and other placental mammals, which instead rely mainly on nucleotide excision repair.

MB502T Mid Term Verified

Q93

Replication start on which strand___

A) Leading strand
B)
C)
D)

AI Explanation

Replication begins with the synthesis of a primer on the leading-strand template. DNA polymerase then extends the leading strand continuously in the 5′ to 3′ direction.

MB502T Mid Term Verified

Q94

Which enzyme play major role in replication___

A) DNA polymerase
B)
C)
D)

AI Explanation

DNA polymerase plays the major role in DNA replication by adding nucleotides to the growing DNA strand. It also contributes to replication accuracy through proofreading in many DNA polymerases.

MB502T Mid Term Verified

Q95

Nucleic acid to protein ratio in influenza virus___

A) 1%
B)
C)
D)

AI Explanation

Influenza virus contains a relatively small proportion of nucleic acid compared with its total protein content. The nucleic acid to protein ratio is given as approximately 1% in the stated course material.

MB502T Mid Term Verified

Q96

Metabolic ions reason of endogenous mutation____

A) DNA mutation
B)
C)
D)

AI Explanation

Metabolic processes can generate reactive intermediates and other endogenous factors that damage DNA. Such damage can lead to DNA mutations if it is not correctly repaired.

MB502T Mid Term Verified

Q97

Which RNA bind with anticodon____

A) tRNA
B)
C)
D)

AI Explanation

Transfer RNA (tRNA) contains an anticodon sequence that pairs with the complementary codon on mRNA. This ensures that the appropriate amino acid is added during translation.

MB502T Mid Term Verified

Q98

Superoxide dismutase which convert _____ into hydrogen peroxide and oxygen ___

A) superoxide radicals
B)
C)
D)

AI Explanation

Superoxide dismutase converts superoxide radicals into hydrogen peroxide and oxygen. This reaction is an important cellular defense against reactive oxygen species.

MB502T Mid Term Verified

Q99

Which enzyme breaks the dsDNA and passes some amount of DNA from the break___

A) Topoisomerase
B)
C)
D)

AI Explanation

Topoisomerases temporarily break DNA strands to relieve torsional stress and allow DNA strands or segments to pass through the break. They then reseal the DNA backbone.

MB502T Mid Term Verified

Q100

The most common cyclobutane pyrimidine dimer is ___

A) thymine-thymine
B)
C)
D)

AI Explanation

Thymine-thymine cyclobutane pyrimidine dimers are the most common type of CPD produced by ultraviolet radiation. They distort the DNA structure and can interfere with replication and transcription.