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

TLTTLLTTLl  TtLL  TtLl

TlTTLl         TTll         TtLl         Ttll

tLTtLL         TtLl         ttLL         ttLl

tlTtLl         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

correct answer is option a.

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