MCQ Bank

A nucleoside consists of a nitrogenous base attached to a sugar. A nucleotide is a nucleoside plus one or more phosphate groups, so removing phosphoric acid from a nucleotide gives a nucleoside.

MB502T Mid Term Verified

Q42

The group of adjacent nucleotides are joined by____

A) Phosphodiester bond
B)
C)
D)

AI Explanation

Adjacent nucleotides in nucleic acids are connected through phosphodiester bonds. These bonds link the 3′ hydroxyl group of one sugar to the 5′ phosphate group of the next nucleotide.

MB502T Mid Term Verified

Q43

RNA can base-pair with complementary regions of either___

A) RNA or DNA
B)
C)
D)

AI Explanation

RNA can form complementary base pairs with another RNA molecule or with a DNA strand. This pairing is important in processes such as RNA secondary-structure formation and RNA-DNA hybridization.

MB502T Mid Term Verified

Q44

The overall three dimensional arrangement of all atoms in a protein is referred as____

A) Tertiary structure of protein
B)
C)
D)

AI Explanation

The tertiary structure describes the complete three-dimensional arrangement of a protein's atoms within a single polypeptide chain. It is stabilized by interactions among amino acid side chains and other molecular forces.

MB502T Mid Term Verified

Q45

Which of following purine base is present in RNA__

A) Guanine
B)
C)
D)

AI Explanation

Guanine is a purine nitrogenous base found in both DNA and RNA. The other purine base, adenine, is also present in RNA.

MB502T Mid Term Verified

Q46

Which nucleotides are considered as purine__

A) adenine & Guanine
B)
C)
D)

AI Explanation

Adenine and guanine are the two purine bases found in nucleic acids. They have a characteristic fused double-ring structure.

MB502T Mid Term Verified

Q47

Avery performed his experiment to give evidence about DNA is heredity material___

A) 1944
B)
C)
D)

AI Explanation

Oswald Avery and his colleagues published their landmark experiment in 1944. Their work provided strong evidence that DNA, rather than protein, is the hereditary material responsible for bacterial transformation.

MB502T Mid Term Verified

Q48

The helical twist of the α-helix found in all proteins is__

A) right-handed
B)
C)
D)

AI Explanation

The α-helix found in naturally occurring proteins is predominantly right-handed. Its structure is stabilized by hydrogen bonds between backbone carbonyl and amino groups.

MB502T Mid Term Verified

Q49

The DNA polymerase require a primer with a free___

A) 3’-OH
B)
C)
D)

AI Explanation

DNA polymerase cannot initiate DNA synthesis without a primer. It extends the primer by adding nucleotides to its free 3′-OH group.

MB502T Mid Term Verified

Q50

The bond angles in protein primary structure resulting from rotations at C are labelled (psi) for the____ bond ___

A) Alpha C-C
B)
C)
D)

AI Explanation

The psi (ψ) angle represents rotation around the Cα–C bond in the protein backbone. The phi (φ) angle, in contrast, represents rotation around the N–Cα bond.

MB502T Mid Term Verified

Q51

First enzyme diastase discovered by___

A) Anseime Payen in 1833
B)
C)
D)

AI Explanation

The first enzyme, diastase, was discovered by Anselme Payen and Jean-François Persoz in 1833. Diastase was identified for its ability to break down starch.

MB502T Mid Term Verified

Q52

About ____ of all amino acid residues in polypeptides are found in α-helices.__

A) one-forth
B)
C)
D)

AI Explanation

Approximately one-fourth of all amino acid residues in polypeptides are found in α-helices. The α-helix is a common secondary structure stabilized by regular backbone hydrogen bonding.

MB502T Mid Term Verified

Q53

The palm domain of DNA Polymerase is composed of a ___ sheet and contains the primary elements of the catalytic site.__

A) Beta
B)
C)
D)

AI Explanation

The palm domain of DNA polymerase contains a central beta sheet. This domain forms important parts of the enzyme's catalytic site responsible for nucleotide addition.

MB502T Mid Term Verified

Q54

A typical human cell contains about___ million copies of each kind of histone___

A) 60
B)
C)
D)

AI Explanation

A typical human cell contains roughly 60 million copies of each major type of histone. The large number reflects the extensive packaging of the human genome into nucleosomes.

MB502T Mid Term Verified

Q55

The binding of histones to phosphate group of a nucleotide is aided by___ charged site chain of ___:

A) Positive, Arginine
B)
C)
D)

AI Explanation

Histones bind strongly to the negatively charged phosphate groups of DNA because they contain positively charged amino acid side chains. Arginine is particularly important in these electrostatic interactions.

MB502T Mid Term Verified

Q56

Which shows the correct complimentary base pairing of DNA ___

A) A-T, G-C
B)
C)
D)

AI Explanation

DNA follows complementary base pairing rules in which adenine pairs with thymine and guanine pairs with cytosine. These specific hydrogen-bonding patterns help maintain the structure of the DNA double helix.

MB502T Mid Term Verified

Q57

The nucleotide containing nitrogenous base cytosine is known as:

A) Deoxycytidylate
B)
C)
D)

AI Explanation

Deoxycytidylate is the DNA nucleotide containing the nitrogenous base cytosine. It consists of cytosine attached to deoxyribose and a phosphate group.

MB502T Mid Term Verified

Q58

A nucleosome has about ___ nucleotides in eukaryotic genome__

A) 400
B)
C)
D)

AI Explanation

A nucleosome core contains about 146 base pairs of DNA, while the nucleosome plus linker DNA is often discussed as roughly 200 base pairs. The stated option of 400 is therefore the closest available choice in the provided question, although it is not the standard nucleosome DNA value.

MB502T Mid Term Verified

Q59

The percentage of nucleic acid in relation to protein is about ____ for the influenza virus__

A) 1%
B)
C)
D)

AI Explanation

Influenza virus particles contain predominantly protein, with nucleic acid making up only a small proportion of the total particle mass. The value given in the question is approximately 1%.

MB502T Mid Term Verified

Q60

CH3 Group attached at___ of thymine nitrogenous base__

A) C5
B)
C)
D)

AI Explanation

Thymine differs from uracil by having a methyl (CH3) group attached at the C5 position of its pyrimidine ring. This methyl group is characteristic of thymine in DNA.