Question

Mendels second law is often referred to as the law of independent assortment . create an example to illustrate it and chi-square to verify the results

Answer 1

One example is given to demonstrate the chi-square test.

Total progeny = 1624

Expected number of Red eyed & Long toed progeny = 9/16 *1624 = 913.5

Expected number of Red eyed & short toed progeny = 3/16 *1624 = 304.5

Expected number of Blue eyed & long toed progeny = 3/16 *1624 = 304.5

Expected number of blue eyed & short toed progeny = 1/16 *1624 = 101.5

Phenotype	Observed(O)	Expected (E)	O-E	(O-E)2	(O-E)2/E
Red eyed & Long toed	905	913.5	-8.5	72.25	0.08
Red eyed & short toed	305	304.5	0.5	0.25	0.00
Blue eyed & long toed	312	304.5	7.5	56.25	0.18
Blue eyed & short toed	102	101.5	0.5	0.25	0.00
Total	1624	1624			0.26

Ch-square = X^2 = 0.26

Degree of freedom = No. of phenotypes -1

Df = 4-1=3

The Chi-square value (0.26) is less than critical (p) value (7.81). So the given data is consistant with expected results. So we can accept null hypothesis and the genes are assorted independently