#Question id: 1255
#Unit 4. Cell Communication and Cell Signaling
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?
#Question id: 12562
#Unit 10. Ecological Principles
#Question id: 10158
#Unit 6. System Physiology – Plant
Following are some statements regarding CO2 assmilation;
a.) The reduction process-Hydroxypyruvate convert into Glycerate in Peroxisomes in Glycolate pathway
b.) In Calvin-Benson cycle action of Transketolase produces erythrose 4-phosphate and xylulose 5-phosphate during regeneration step
c.) In C4 cycle phosphoenolpyruvate carboxylase (PEPCase), catalyzes the initial carboxylation in mesophyll cells close to the external atmosphere
d.) The stomata of CAM plants open at night
Which of the following above statements combination TRUE?
#Question id: 1101
#Unit 4. Cell Communication and Cell Signaling
The activity of adenylyl cyclase is essentially the opposite of which of the following enzymes?
#Question id: 10343
#Unit 6. System Physiology – Plant
In many plants, nitrate is assimilated in the root as well as in the shoot according to their native place. Some of the given statements about nitrate assimilation;
a) If plants native to temperate region assimilate NO3- at root
b) If plants native to temperate region assimilate NO3- at shoot
c) Plants native to tropical or subtropical region assimilate NO3- at root
d) Plants native to tropical or subtropical region assimilate NO3- at shoot
Which of the following combination from above statements is correct?