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TLS Online TPP Program

#Question id: 12657

Experiments performed in the laboratory of Anne Osbourn at the John Innes Centre  utilized genetic approaches to demonstrate the role of saponins in defense against pathogens of oat. If Mutant oat lines then,

#Unit 6. System Physiology – Plant
  1. Increase saponin  levels had more resistance to fungal pathogens than wild-type oats.
  2. reduced saponin levels had much less resistance to fungal pathogens than wild-type oats.
  3. Increase saponins levels had much less resistance to fungal pathogen than wild-type oats.
  4. reduced saponin levels had more resistance to fungal pathogens than wild type oats.
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TLS Online TPP Program

#Question id: 12183

#Unit 1. Molecules and their Interaction Relevant to Biology

Following statements are regarding to regulation of S phase and mitotic cyclin levels in budding yeast.
A. In late anaphase, the anaphase-promoting complex (APC/C) ubiquitinylates S phase and mitotic cyclins.
B. In late anaphase, the anaphase-promoting complex (APC/C) phosphorylates S phase and mitotic cyclins.
C. During exit from mitosis and G1, Cdh1 is dephosphorylated and active; during S phase and mitosis, Cdh1 is phosphorylated and dissociates from APC/C, and APC/C becomes inactive.
D. During exit from mitosis and G1, Cdh1 is phosphorylated and active; during S phase and mitosis, Cdh1 is dephosphorylated and dissociates from APC/C, and APC/C becomes inactive.
E. The G1/S phase CDKs, which themselves are not APC/CCdh1 substrates, phosphorylate Cdh1 at the G1–S phase transition.
F. The G1/S phase CDKs, which themselves are not APC/CCdh1 substrates, ubiquitinylates Cdh1 at the G1–S phase transition.
Which of the following combination is correct?
TLS Online TPP Program

#Question id: 18219

#Unit 1. Molecules and their Interaction Relevant to Biology

Pseudoknot loop refers to 
TLS Online TPP Program

#Question id: 2636

#Unit 1. Molecules and their Interaction Relevant to Biology

Which of the following events occur when E. coli is starved for tryptophan?

I.  The ribosome translates leader peptide completely

II. Transcription reads through attenuator into trp EDCBA

III. Tryptophanyl tRNA is not formed

IV. A stem loop structure involving regions 3 and 4 is formed at attenuator site
TLS Online TPP Program

#Question id: 837

#Unit 1. Molecules and their Interaction Relevant to Biology

Increasing order of free energy in unfolded to folded conformation of the proteins, the correct order is,
TLS Online TPP Program

#Question id: 835

#Unit 1. Molecules and their Interaction Relevant to Biology

The minor clefts and gullies on the sides of the funnel that will be false energy minima, it represents,
TLS Online TPP Program

#Question id: 1520

#Unit 1. Molecules and their Interaction Relevant to Biology

Following statements are regarding to enzymatic processing of benzo(a)pyrene to a more potent mutagen and carcinogen.

A. Liver enzymes, particularly P-450 enzymes, modify benzo(a)pyrene in a series of reactions, producing 7,8-diol-9,10-epoxide, a highly potent mutagenic species that reacts with DNA primarily at the N2 atom of a guanine base.

B. The adduct, (+)-trans-anti-B(a)P-N2-dG, causes polymerase to insert an A rather than a C opposite the modified G base. Next time the DNA is replicated, a T will be inserted opposite the A, and the mutation will be complete.

C. Potent mutagen majorly causes conversion of guanine (G) to thymine (T) bases, a transition mutation.

D. When this potent mutagen applied to cultured bronchial epithelial cells, activated benzo(a)pyrene induces many mutations, including activating mutations at codons 175, 248, and 273 of the p53 gene.

Which of the following statements are correct?