Download punnett square set2 Bunn-fish

Biology
Name__________________________________________
Date____________________ Block__________________
w/Mr. Hubert
Genetics Bunn-fish problem set
In Bunn-fish, square tails (T) is dominant over round tails (t).
If a purebred square tail Bunn fish is crossed with a hybrid square tail Bunn-fish, what would
be genetic outcome of this cross?
TT
x
Tt
Genotype is the genetic make up of the
zygote which results from the cross.
Homozygous dominant is one possible
genotype (TT)
"purebred"
Homozygous recessive is another possible
genotype (t t )
"purebred"
What percentage of the offspring (zygotes)
would we expect to be
Square tailed: ______________
Round tailed: _______________
1
Heterozygous is the last possible
genotype (T t)
"hybrid"
Phenotype is the physical expression of a
trait......in this case there are two
phenotypes, square tails and round tails
JT Hubert
Biology
2020/21
2. What would be the result of a cross between a Heterozygous male Bunn-fish and a
round tailed female Bunn-fish.
_______________
x
____________
What percentage of the offspring
(zygotes) would we expect to be:
Square tailed:_________
Round tailed: _________
3. In our third genetic cross, we will cross two hybrid (heterozygous) Bunn-fish.
_________________ x ________________
What percentage of the offspring
(zygotes) would we expect to be:
Square tailed: ______________
Round tailed: _______________
4. Why is it that a heterozygous Bunn-fish is square tailed and not round tailed?
__________________________________________________________________________
__________________________________________________________________________
2
JT Hubert
Biology
2020/21