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TLS Online TPP Program

#Question id: 649

Choose INCORRECT statement from the following

#Unit 1. Molecules and their Interaction Relevant to Biology

  1. The rates of enzymatically catalyzed reactions are typically 106 to 1012 times greater than those of the corresponding uncatalyzed reactions

  2. The catalytic activities of many enzymes vary in response to the concentrations of substances other than their substrates.

  3. When the reaction involves two molecules, such as the association reaction P + Là PL, it is called second order, and its rate constant (ka) has units of M-2 s-1

  4. When the reaction involves one molecule, such as the dissociation reaction PL à P + L, the reaction is first order and the rate constant (kd) has units of (s-1).

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TLS Online TPP Program

#Question id: 4714

#Unit 11. Evolution and Behavior

After the drought of 1977, researchers hypothesized that on the Galápagos Island Daphne Major, medium ground finches with large, deep beaks survived better than those with smaller beaks because they could more easily crack and eat the tough Tribulus cistoides fruits. A tourist company sets up reliable feeding stations with a variety of bird seeds (different types and sizes) so that tourists can get a better look at the finches. Which of these events is now most likely to occur to finch beaks on this island?
TLS Online TPP Program

#Question id: 23465

#General Aptitude

Statement— Should there be an upper age limit of 65 years for contesting Parliamentary/ Legislative Assembly elections?
Arguments—
I) Yes. Generally, people above the age of 65 lose their dynamism and will power.
II) No. The life span is so increased that people remain physically and mentally active even up to the age of 80.
TLS Online TPP Program

#Question id: 557

#Unit 1. Molecules and their Interaction Relevant to Biology

The number of substrate molecules converted to product in a given unit of time by a single enzyme molecule at saturation is referred to as the:
TLS Online TPP Program

#Question id: 19044

#Unit 13. Methods in Biology

Which of the following techniques would be most useful to identify as well as quantify the presence of a known impurity in a drug substance? 
TLS Online TPP Program

#Question id: 4104

#Unit 3. Fundamental Processes

Consider following statements for catalytic mechanism of RNA polymerase

A. RNA synthesis by RNA polymerase. The reaction involves two Mg2+ ions, coordinated to the phosphate groups of the incoming nucleoside triphosphates (NTPs)

B. Three Asp residues, which are highly conserved in the RNA polymerases of all species. One Mg2+ ion facilitates attack by the 39-hydroxyl group on the phosphate of the NTP; the other Mg2+ ion facilitates displacement of the pyrophosphate, and both metal ions stabilize the pentacovalent transition state.

C. About 17 bp of DNA are unwound at any given time. RNA polymerase and the transcription bubble move from left to right along the DNA as shown, facilitating RNA synthesis. Movement of an RNA polymerase along DNA tends to create negative supercoils (overwound DNA) ahead of the transcription bubble and positive supercoils (underwound DNA) behind it.

D. The RNA polymerase is in close contact with the DNA ahead of the transcription bubble as well as with the separated DNA strands and the RNA within and immediately behind the bubble. A channel in the protein funnels new NTPs to the polymerase active site. The polymerase footprint encompasses about 35 bp of DNA during elongation.