TLS Online TPP Program

#Question id: 1255


Following statements are regarding to the mechanism of action of cholera toxin.

A. cholera toxin is a homodimeric protein, target G proteins, interfering with normal signaling in host cells.

B. cholera toxin associates with a small G protein, known as ARF6.

C. association with ARF6 activates cholera toxin, which catalyzes the transfer of ADP-ribose from NAD+ to the critical Arg residue in the P loop of the alpha subunit of Gs.

D. ADP-ribosylation blocks the GEF activity of Gs and thereby renders Gs permanently inactive.

E. This results in continuous activation of the adenylyl cyclase of intestinal epithelial cells, chronically high cAMP, and active PKA dephosphorylates the CFTR Cl- channel and a sodium-proton exchanger in the intestinal epithelial cells.

Which of the following combination is correct?

#Unit 4. Cell Communication and Cell Signaling
  1. B and C

  2. A, B, D and E

  3. A, D and E

  4. D only

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TLS Online TPP Program

#Question id: 24215

#Unit 1. Molecules and their Interaction Relevant to Biology

What are the target of AMP in the glycolysis and the gluconeogenesis in the same plane

TLS Online TPP Program

#Question id: 24214

#Unit 1. Molecules and their Interaction Relevant to Biology

Which molecule coordinately activate glycolysis and at the same time inhibit gluconeogenesis

TLS Online TPP Program

#Question id: 24213

#Unit 1. Molecules and their Interaction Relevant to Biology

Choose the incorrect statement

TLS Online TPP Program

#Question id: 24212

#Unit 1. Molecules and their Interaction Relevant to Biology

Choose the correct statement
a. Hexokinases IV remains sequesters in the nucleus in case of high F-6-P and high ATP
b. Hexokinases IV remains sequesters in the cytoplasm in case of high F-6-P and high ATP
c. Hexokinase requires Mg+2 for its activity, because the true substrate of the enzyme is not ATP4- but the MgATP2- complex.
d. Hexokinase requires Mg+2 for its activity, because the true substrate of the enzyme is MgATP4- but not the MgATP2- complex.

TLS Online TPP Program

#Question id: 24211

#Unit 1. Molecules and their Interaction Relevant to Biology

Plot of hexokinase IV (Glucokinase) is different While Hexokinases I, II, and III have similar kinetic properties. So, in given graph which of the following represents hexokinase IV and Hexokinases I, II, and III
a. i is representing Hexokinases IV
b. ii is representing Hexokinases I, II, and III
c. i is representing Hexokinases I, II, and III
d. ii is representing Hexokinases IV
Choose the correct option

TLS Online TPP Program

#Question id: 24210

#Unit 1. Molecules and their Interaction Relevant to Biology

The human genome encodes four different hexokinases (I to IV), all of which catalyze the same reaction. If Two or more enzymes that catalyze the same reaction but are encoded by different genes are called to be