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?

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#Question id: 11459

#Unit 7. System Physiology – Animal

Partial or complete loss of hearing (deafness) can be caused by damage to the ________.

I) axons of the neurons associated with each hair cell that carry information to the brain

II) hair cells (the sensory receptors) in the cochlea

III) tympanic membrane, or eardrum

TLS Online TPP Program

#Question id: 11460

#Unit 7. System Physiology – Animal

The round window ________.

I) dampens fluid vibrations

II) collects sound pressure waves

III) detects the frequency of sounds

TLS Online TPP Program

#Question id: 11461

#Unit 7. System Physiology – Animal

Elephants hear sounds that are too low for humans to hear. This sensitivity is primarily due to the differences in the ________.

TLS Online TPP Program

#Question id: 11462

#Unit 1. Molecules and their Interaction Relevant to Biology

1. C-terminal of all 20 amino acid is same.

2. N-terminal of all 20 acid is same.

3. N-terminal of all amino acid is same except one .

4. All acidic amino acid have corboxy terminus in their side chain.

5. All basic amino acid have H3N+ group in their side chain.

Find the correct statements

TLS Online TPP Program

#Question id: 11463

#Unit 1. Molecules and their Interaction Relevant to Biology

If trypsin cleaved at Lys/Arg C-terminus, then total no. of fragment will be observed for given sequence

TLS Online TPP Program

#Question id: 11464

#Unit 1. Molecules and their Interaction Relevant to Biology

Green fluorescent protein consists of a chain of 238 amino acid residues. The light-emitting group is a derivative of three consecutive amino acids are