A nucleosome string viewed under an electron microscope appears as?
When chromatin is viewed under an electron microscope, the nucleosomes (DNA wrapped around histone octamers) linked by spacer DNA look like "beads on a string".
Question 72 of 668
📘 CLASS XII
What is the function of DNA Ligase?
DNA Ligase catalyzes the formation of a phosphodiester bond between the 3-prime hydroxyl end of one DNA fragment and the 5-prime phosphate end of another, effectively joining nicks in the backbone.
Question 73 of 668
📘 CLASS XII
The process of copying genetic information from one strand of DNA into RNA is termed?
Transcription is the specific process where the genetic information stored in DNA is copied into a complementary strand of RNA by the enzyme RNA polymerase.
Question 74 of 668
📘 CLASS XII
In a DNA double helix, the two strands are?
The two strands of the DNA double helix run in opposite directions. One runs 5-prime to 3-prime, and the other runs 3-prime to 5-prime. This antiparallel orientation is essential for base pairing and replication.
Question 75 of 668
📘 CLASS XII
Which of the following is NOT a stop codon?
UAA (Ochre), UAG (Amber), and UGA (Opal) are the three stop codons that signal the termination of translation. UGG is the codon for Tryptophan.
Question 76 of 668
📘 CLASS XII
The sequence of the structural gene in the Lac operon is?
The structural genes in the Lac operon are arranged in the order lacZ, lacY, and lacA. Z codes for beta-galactosidase, Y for permease, and A for transacetylase.
Question 77 of 668
📘 CLASS XII
Satellite DNA is useful in?
Satellite DNA shows a high degree of polymorphism (VNTRs) unique to individuals. This property makes it the basis for DNA profiling or fingerprinting used in forensic science to identify individuals.
Question 78 of 668
📘 CLASS XII
The inducer of the Lac operon is?
Lactose (or its isomer allolactose) functions as the inducer. Its presence signals the bacteria to produce the enzymes necessary to metabolize it by binding to the repressor and inactivating it.
Question 79 of 668
📘 CLASS XII
Which molecule is removed from the 5-prime end of hnRNA during processing?
During processing, nothing is removed from the 5-prime end; instead, a cap is *added*. Introns are removed from the internal sequence via splicing.
Question 80 of 668
📘 CLASS XII
Which polymerase removes RNA primers in prokaryotes?
DNA Polymerase I has 5-prime to 3-prime exonuclease activity, which allows it to remove the RNA primers and replace them with DNA nucleotides during replication.
