A nucleosome contains _______ molecules of histones.

[Molecular-Basis-of-Inheritance] [class-xii ]

• 4
• 6
• 8
• 10
Correct Option: C  [ 8 ]

Remark: The core is an octamer (8).

Histone H1 is associated with _______

[Molecular-Basis-of-Inheritance] [class-xii ]

• The core particle
• Linker DNA
• The chromosome scaffold
• None
Correct Option: B  [ Linker DNA ]

Remark: H1 binds to linker DNA.

The number of hydrogen bonds between G and C is _______

[Molecular-Basis-of-Inheritance] [class-xii ]

• 1
• 2
• 3
• 4
Correct Option: C  [ 3 ]

Remark: G-C has 3 hydrogen bonds.

DNA synthesis occurs during _______ phase.

[Molecular-Basis-of-Inheritance] [class-xii ]

• G1
• S
• G2
• M
Correct Option: B  [ S ]

Remark: DNA synthesis is S phase.

The enzyme used to join DNA fragments is _______

[Molecular-Basis-of-Inheritance] [class-xii ]

• Ligase
• Polymerase
• Endonuclease
• Helicase
Correct Option: A  [ Ligase ]

Remark: Ligase joins fragments.

Okazaki fragments are joined by _______

[Molecular-Basis-of-Inheritance] [class-xii ]

• Primase
• Polymerase I
• Polymerase III
• Ligase
Correct Option: D  [ Ligase ]

Remark: Ligase joins Okazaki fragments.

RNA primer is removed by _______

[Molecular-Basis-of-Inheritance] [class-xii ]

• DNA Polymerase I
• DNA Polymerase II
• DNA Polymerase III
• Ligase
Correct Option: A  [ DNA Polymerase I ]

Remark: Pol I removes RNA primers.

During DNA replication, the strands separate by _______

[Molecular-Basis-of-Inheritance] [class-xii ]

• DNA polymerase
• Topoisomerase
• Helicase
• Gyrase
Correct Option: C  [ Helicase ]

Remark: Helicase separates strands.

The enzyme that cuts DNA at specific sites is _______

[Molecular-Basis-of-Inheritance] [class-xii ]

• Ligase
• Polymerase
• Restriction endonuclease
• Exonuclease
Correct Option: C  [ Restriction endonuclease ]

Remark: Restriction enzymes cut at specific sites.

_______ is used as a vector for cloning large DNA fragments.

[Molecular-Basis-of-Inheritance] [class-xii ]

• Plasmid
• Cosmid
• BAC
• Phage
Correct Option: C  [ BAC ]

Remark: BACs clone large fragments.