The t locus is involved in the production of tails in a mouse; tt individuals are without tails, whereas TT and Tt have tails. The l locus is involved in the color of tails: assuming that they have tails, individuals that are ll have light tails, whereas all others have dark tails. The two loci are on different chromosomes. In a dihybrid cross between TtLl individuals, what fraction will have light tails?

1/4 are light tailed mouse

Explanation:

Given

T (With Tail) is dominant over t (tailless)

L (dark tail) is dominant over l (light color tail)

A cross is made between TtLl and TtLl

TL Tl tL tl

TL TTLL TTLl TtLL TtLl

Tl TTLl TTll TtLl Ttll

tL TtLL TtLl ttLL ttLl

tl TtLl Ttll ttLl ttll

Genotype of offspring are -

TTLL - 1

TTLl - 2

TtLL - 2

TtLl - 4

TTll - 1

Ttll - 2

ttLL - 1

ttLl - 1

ttll - 1

Light colored tail species - TTll, Ttll, ttll

Out of 16, 4 are light colored

Thus 1/4 are light tailed mouse