00:01
For this one, we have the results of cross for a, b, which is 121, and we have a, b, that is 107, small a, b, which is 115, recessive a and b, that is 93.
00:26
So the total number of offspring will be equal to 436.
00:31
It is given that the results are from a dihybrid test cross, and this means a heterozygous f1, a and b was mated to homozygous recessive a and b.
00:45
Thus required, if we were going to do some test cross between this one, the gametes from first parent are basically homozygous a and b, big a, small a, big b, and small a, and b.
01:00
And from the second parent will be type only recessive a and b.
01:06
All the four types should occur in equal proportion that is 1 is to 1 is to 1 is to 1.
01:13
Thus expected number of each type of progeny is 436 divided by 4, we will have 109.
01:21
So if we were going to put this one on a table, so we have the phenotype, we have the observe expected, observed minus expect, observed minus expected squared observe minus expected squared square divide divide e so we have the phenotype and basically for the first one we have 121, 107 115 and basically we have another one so we have after before 115 or after 115 rather so we have 115, recessive a and b, that is 93, expected 109, 1009, and 109.
02:23
So this is a total of 436...