Question: In red-eared hephelumps, three genes are linked on the same chromosome. Tall is dominant to dwarf…

In red-eared hephelumps, three genes are linked on the same
chromosome. Tall is dominant to dwarf, Black coat color is dominant
to gray coat color, and Long noses are dominant to short noses. We
will use alleles T and t, B and b, L and l for height, coat color
and nose length respectively. An individual that is true-breeding
for dominant traits is crossed with an individual that is
true-breeding for recessive traits to produce a trihybrid F1
generation. An F1 individual was then used in a testcross that
produced the following offspring.

300 Tall, black, long nosed 20 Tall, black, short nosed
8 Tall, gray, short nosed
1 Tall, gray, long nosed
298 Dwarf, gray, short nosed 21 Dwarf, gray, long nosed

9 Dwarf, black, long nosed
1 Dwarf, black, short nosed
How many of the offspring are parental
types?_________________________

How many of the offspring are recombinant
types?_______________________
How many of the offspring are the result of a double
crossover?______________ Which locus is in the middle?____
_____________________________
In the 20 Tall, black, short nosed and 21 Dwarf, gray, long nosed
offspring, which locus crossed over?______
______________________________________________

In the 8 Tall, gray, short nosed and 9 Dwarf, black, long nosed
offspring, which locus crossed over?_________
________________________________________________
What is the genotype of the testcross parent of the F2
generation?___ _________
What is the genotype for each of the following types of F2
offspring from this dihybrid testcross?

Dwarf, gray, short
nosed___________________________________________
Tall, gray, long
nosed__________________________________________________ Dwarf,
black, short nosed_____________________________________________