Phenotypes & Genotypes
Objectives: Correctly predict genotype and phenotype
Name: ____________________
Date: _________
_____
Section:
Read below to review.
Phenotype is the observable trait or appearance of the organism.
Genotype is the genetic makeup that describes the trait.
Alleles can be either dominant or recessive.
P – purple flowers (dominant)
p – white flowers (recessive)
(Big letter is always dominant.)
Dominant alleles control the phenotype if they are present, regardless of what else is present.
Recessive alleles control the phenotype only if no dominant alleles are present.
1. Gene:
Alleles:
Flower color
(P): Purple flower(dominant)
(p): White flower (recessive)
Genotype
PP
Phenotype
Pp
pp
____ OR ____
Purple
White
2. Gene:
Alleles:
Snail antennae color
(Y): Yellow (dominant)
(y): White (recessive)
Genotype
YY
Phenotype
Yy
yy
____OR ____
Yellow
White
3. Gene:
Alleles:
Pigeon wing color
(G): Dark grey (dominant)
(g): Light grey(recessive)
Genotype
GG
Phenotype
Gg
gg
Light grey
4. Gene:
Alleles:
Parakeet tail length
(T): Long tail (dominant)
(t): Short tail (recessive)
____OR ____
Dark grey
Genotype
TT
Phenotype
Tt
tt
____ OR ____
Long tail
Short tail
5. Fill in the blanks with DOMINANT or RECESSIVE.

If a person has two copies of the dominant gene, they show the __________________
phenotype.

If a person has one copy of the dominant gene and one copy of the recessive gene, they show
the _____________________ phenotype.

If a person has two copies of the recessive gene, they show the ______________________
phenotype.
6. If a person shows the recessive phenotype for a trait, their genotype could be… (circle one or
more)
AA
Aa
aa
7. If a person shows the dominant phenotype for a trait, their genotype could be… (circle one or
more)
AA
Aa
aa