Both PHYA and PHYB activate the transcription of LHCB gene for its expression, there following events occur during the activation of LHCB gene such as;

a) PhyA, both form is activated Pr and Pfr by phosphorylation Pr form move into the nucleus activate the light-regulated gene expression during degradation of  the HY5 by COP1

b) PhyA, Pfr form is activated by phosphorylation and move into the nucleus where it’s export the COP1 out of the nucleus, and activate the light-regulated gene expression

c) Phy B, activated phosphorylated Pfr form is move into the nucleus and binds to a dimer of the transcription factor PIF3, by inibiting PIF3 expression activate the transcription of LHCB gene by intermediate transcriptional factor MYB

d) Phy B, activated unphosphorylated Pfr form is move into the nucleus and binds to a monomer of the transcription factor PIF3, by inibiting PIF3 expression activate the transcription of MYB gene by intermediate transcriptional factor LHCB

Which of the following combination of the above statements of phytochrome forms is correct?

#Question id: 4269

#Unit 3. Fundamental Processes

The kinase P-TEFb

A. Is recruited to polymerase by transcriptional activators

B. Phosphorylates the serine 2&5 of the CTD repeats for elongation

C. Phosphorylates SPT5 and TAT-SF1

#Question id: 4270

#Unit 3. Fundamental Processes

RNA helicase contains characteristic

#Question id: 4271

#Unit 3. Fundamental Processes

To participate successfully in the peptidyl transferase reaction, the tRNA must rotate into the peptidyl transferase center of the large subunit in a process called as

#Question id: 4272

#Unit 3. Fundamental Processes

There are two classes of release factors for translation termination. Choose correct statements

A. Class I release factors recognize the stop codons and trigger hydrolysis of the peptide chain from the tRNA in the P-site.

B. Prokaryotes have two class I release factors called RF1 and RF2. RF1 recognizes the stop codon UGA, UAA and RF2 recognizes the stop codon UAG and UAA.

C. In eukaryotic cells, there is a single class I release factor called eRF1 that recognizes all three stop codons.

D. Class II release factors stimulate the dissociation of the ribosome after release of the polypeptide chain.

#Question id: 4273

#Unit 3. Fundamental Processes

80S initiation complex includes

#Question id: 4274

#Unit 3. Fundamental Processes

One mechanism that contributes to the fidelity of codon recognition involves the 16S rRNA other than initiation. Which of the following statements are correct in this phenomenon?

A. Codon recognition involves two adjacent uracil residues in the 16S rRNA component

B. The adjacent residues in the 16S rRNA do not discriminate between G:C or A:U base pairs and recognize either as correct

C. Even a single mismatch in the codon–anticodon base pairing alters the position of EF-Tu, reducing its ability to interact with the factor-binding center 16s rRNA, leads to a dramatic reduction in EF-Tu GTPase activity

D. Pyrophasphatic editing is key mechanism to ensure fidelity