During DNA replication, the leading strand is synthesized?
The leading strand is synthesized continuously in the 5-prime to 3-prime direction towards the replication fork.
Question 582 of 668
📘 CLASS XII
RNA polymerase III is responsible for transcription of?
RNA Polymerase III transcribes tRNA, 5S rRNA, and snRNAs.
Question 583 of 668
📘 CLASS XII
In the absence of lactose, the repressor binds to which region of the Lac Operon?
When lactose is absent, the repressor binds to the operator region, blocking RNA polymerase from transcribing the genes.
Question 584 of 668
📘 CLASS XII
The coding sequences of eukaryotic genes are called?
Exons are the coding sequences or expressed sequences that appear in mature/processed RNA.
Question 585 of 668
📘 CLASS XII
Which process involves the removal of introns?
Splicing is the process of removing non-coding introns from the primary transcript.
Question 586 of 668
📘 CLASS XII
A nucleosome consists of DNA wrapped around a core of how many histone molecules?
The nucleosome core is a histone octamer, consisting of 8 histone molecules (two each of H2A, H2B, H3, and H4).
Question 587 of 668
📘 CLASS XII
Euchromatin is characterized by being?
Euchromatin is the loosely packed, light-staining form of chromatin that is transcriptionally active.
Question 588 of 668
📘 CLASS XII
The DNA dependent DNA polymerase catalyzes polymerization in which direction?
DNA polymerases can only add nucleotides to the 3-prime OH end, so synthesis always proceeds in the 5-prime to 3-prime direction.
Question 589 of 668
📘 CLASS XII
Match List-I with List-II regarding the experiments on genetic material.
List-I (Scientist)
List-II (Contribution)
A. Frederick Griffith
I. Unequivocal proof that DNA is genetic material
B. Avery, MacLeod, McCarty
II. Semi-conservative replication in Eukaryotes
C. Hershey and Chase
III. Transforming Principle
D. Taylor and colleagues
IV. Biochemical characterization of Transforming Principle
Frederick Griffith (1928) discovered the Transforming Principle using Streptococcus pneumoniae. Avery, MacLeod, and McCarty biochemically characterized this principle as DNA by using enzymes like DNase, RNase, and Protease. Hershey and Chase (1952) provided unequivocal proof that DNA is the genetic material using bacteriophages and radioisotopes. Taylor and colleagues proved semi-conservative replication in eukaryotes (Vicia faba) using radioactive thymidine.
Question 590 of 668
📘 CLASS XII
Match List-I with List-II regarding DNA structure dimensions (B-DNA).
List-I (Feature)
List-II (Measurement)
A. Pitch of Helix
I. 0.34 nm
B. Rise per base pair
II. 2.2 meters
C. Diameter of Helix
III. 3.4 nm
D. Length of DNA in human diploid cell
IV. 20 Angstrom (2 nm)
The pitch of the DNA helix (one complete turn) is 3.4 nm (34 Angstrom). The distance or rise between adjacent base pairs is 0.34 nm. The diameter of the B-DNA helix is constant at 20 Angstroms (2 nm). The total length of DNA in a human diploid cell is calculated as 6.6 x 10^9 bp multiplied by 0.34 nm, resulting in approximately 2.2 meters.
