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: 4866

#Unit 8. Inheritance Biology

In a certain diploid plant, the three loci A, B, and C are linked as follows: Assuming 100%   interference, if the plant with genotype ABC/abc is test cross, what proportion of the progeny will be of the genotype a b c/a b c?

#Question id: 4867

#Unit 8. Inheritance Biology

A three point test cross was carried out in Drosophila melanogaster involving three adjacent incomplete link genes A, B and C. arranged in the same order. The distance between A to B is 5 map units (mu) and that between B to C is 10 map. If pure line Drosophila AAbbCC crosses with aaBBcc to produce F1 offspring were allowed to cross with aabbcc result in following offspring genotype?

What is a A, B, C respectively?

#Question id: 4868

#Unit 8. Inheritance Biology

 A mouse cross C/c . D/d X c/c . d/d is made, and in the progeny there are

45% C/c . d/d, 45% c/c . D/d,

5% c/c . d/d, 5% C/c . D/d

What are distance between C and D gene?

#Question id: 4869

#Unit 8. Inheritance Biology

In the plant Arabidopsis, the loci for pod length (L, long; l, short) and fruit hairs (H, hairy; h, smooth) are linked 16 map units apart on the same chromosome. The following crosses were made:

(i) L H/L H X l h/l h = F1

(ii) L h/L h X l H/l H = F1

If the F1’s from (i) and (ii) are crossed, what proportion of the progeny are expected to l h/l h?

#Question id: 4870

#Unit 8. Inheritance Biology

Following gene order is for three points. If Genotype +y +ct +v produced actual number of double cross over gamete is 10 out of total 1000. What is interference value?

#Question id: 4871

#Unit 8. Inheritance Biology

In a testcross of an individual heterozygous for each of three linked genes, the most frequent classes of progeny were A B c/a b c and a b C/a b c, and the least frequent classes were A B C/a b c and a b c/a b c. what is the order of the genes?