TLS Online TPP Program

#Question id: 2897


The transcription of most protein coding genes in mammals (~70 percent) occurs at a lower rate than at TATA box–containing and initiator-containing promoters and begins at any of several alternative start sites within regions of about 100–1000 bp that have an unusually high frequency of CG sequences. Which one of the following best explains it?

#Unit 2. Cellular Organization
  1. CG-rich sequences are bound by histone octamers more tightly than CG-poor sequences because less energy is required to bend around the histone octamer forming a nucleosome.

  2. During housekeeping gene expression, the enzyme methyltransferase is temporarily silenced by miRNA, thus shutting down global methylation.

  3. As soon as the cytosine is methylated in the promoter region, the enzymes of DNA repair pathways remove the methyl group, thereby ensuring gene expression.

  4. A remarkable feature of the CpG islands is that transcription from these elements is initiated in both directions, even though only transcription of the sense strand yields an mRNA.

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TLS Online TPP Program

#Question id: 649

#Unit 1. Structure and Function of Biomolecules

Choose INCORRECT statement from the following

TLS Online TPP Program

#Question id: 650

#Unit 1. Structure and Function of Biomolecules

On the basis of hypothetical binding curve given below, which of the following statement is INCORRECT

TLS Online TPP Program

#Question id: 651

#Unit 1. Structure and Function of Biomolecules

Consider an enzyme catalysed reaction treated with inhibitor. Enzyme kinetic was analysed with Eadie Hofstee equation. A plot of V0 versus V0/[S] for an enzyme-catalyzed reaction is shown below. The control curve was obtained in the absence of inhibitor. Which effect is shown on the enzyme activity when an inhibitor is added to the reaction mixture?

TLS Online TPP Program

#Question id: 652

#Unit 1. Structure and Function of Biomolecules

Two proteins, X and Y, bind to the same ligand, A, with the binding curves shown below. Which of the statement is correct for the graph analysing two proteins?

TLS Online TPP Program

#Question id: 653

#Unit 1. Structure and Function of Biomolecules

For the enzyme-catalyzed reaction S ~ P, Keq = 5, which of the following curves best represents the change in [S] that occurs with time when S is added to a solution containing the appropriate enzyme?

TLS Online TPP Program

#Question id: 653

#Unit 1. Structure and Function of Biomolecules

For the enzyme-catalyzed reaction S ~ P, Keq = 5, which of the following curves best represents the change in [S] that occurs with time when S is added to a solution containing the appropriate enzyme?