Small nuclear RNAs used to process and chemically modify rRNAs are called

• Sca RNAs

• Si RNAs

• Sno RNAs

• Sn RNAs

Leader sequence in some of the protozoan parasites is transcribed elsewhere in the parasite genome and gets joined with several transcripts to make the functional RNA. The joining of the two transcripts occur by the process of

• alternate splicing

• trans splicing

• ligation

• RNA editing

83.

Chirality of DNA is due to

• the bases

• base stacking

• hydrogen bonds between bases

• deoxyribose

In bacteria, heat-shock response is primarily controlled by

• Sigma S (σ^S)

• Sigma 32 (σ³²)

• Sigma E (σ^E)

• Sigma 70 (σ⁷⁰)

In type II splicing

• a 'G-OH' from outside makes a nucleophilic attack on 5'P of first base of intron.

• a free 2'O of an internal adenosine makes a nucelophilic attack on 5'P of first base of intron.

• A 3'O of an internal adenosine makes a nucleophilic attack on 5'P of first base of intron.

• The hydrolysis of last base of exon is carried out by U2/ U4/ U6.

Copying errors occurring during replication are corrected by the proof reading activity of DNA polymerases that recognize incorrect bases

• at the 5'end of the growing chain and remove them by 5' - 3' exonuclease activity.

• at the 3' end of the growing chain and remove them by 5' - 3' exonuclease activity.

• at the 3' end of the growing chain and remove them by 3' - 5' exonuclease activity.

• at the 5' end of the growing chain and remove them by 3' - 5' exonuclease activity.

During each cycle of chain elongation in translation, how many conformational changes does the ribosome undergo that are coupled to GTP hydrolysis?

• Zero

• One

• Two

• Three

The pluripotency of the inner cell mass in mammals is maintained by a core of three transcription factors namely,

• Oct 4, Sox 2 and Nanog

• Oct 4, Sox 2 and Cdx2

• Sox 2, Nanog and Cdx2

• Oct 4, Cdx2 and Nanog

What will happen if DNA is labeled by nick translation while doing DNA foot-printing?

• Nick translation will facilitate better analysis because entire DNA will be labeled and proteins at any region OF DNA can be demarcated with precision.

• This will allow arranging the DNA fragment in the desired order.

• Labeling by random priming maybe be advantageous as it generates smaller fragments that can penetrate tissue easily.

• The linear order of fragments from 5' → 3' end of DNA cannot be arranged.

Eukaryotic DNA polymerase α has tightly associated primase activity but moderate processivity. DNA polymerase ε and δ are highly processive but lack primase, activity. Given below are four statements about leading and lagging strand synthesis in eukaryotes. Which one is true?

• Both leading and lagging strands are synthesized by DNA polymerase α. Moderate processivity is essential to maintain the fidelity of replication.

• Entire leading and lagging strands are synthesized by δ and ε. Eukaryotic replication is a primer independent process.

• Only the lagging strand synthesis needs primer and synthesized by DNA polymerase α.

• Primers for both the strands are synthesized by DNA polymerase α followed by "Polymerase switching" with ε and δ.