Name ___________________________
Date ______________________ Pd ____
Dominant Fly
Genes that determine traits are encoded and arranged linearly on structures called chromosomes found
in the nuclei of most cells. When organisms reproduce, the resulting offspring should receive an equal
number of chromosomes from the mother and the father.
Materials:
Egg, sperm, Insect Parts drawings, colored pencils
Procedures:
1. Use the chromosomes and the Insect Traits Key below to determine the genotype and phenotype of
the offspring. Record the information in Data Table 1.
Insect Traits Key
H – LARGE HEAD
E – RED EYE
P – ANTENNAE PRESENT
h – small head
e – white eyes
p – antennae absent
T – SHORT THORAX
O – ORANGE WING
W – SHORT WINGS
t – long thorax
o – green wings
w – long wings
A – SHORT ABDOMEN
B – BLACK BODY
L – SHORT LEGS
a – long abdomen
b – gray body*
l – long legs
XX – Female
XY – Male
*Body color refers to antennae, head, thorax,
abdomen, and legs.
Data Table 1
Trait
Genotype
Phenotype
Head Size
Hh
Large head
Eye Color
Antennae
2. Open the egg and sperm and examine the chromosomes. Pair up the chromosomes by matching the
traits on them. Use the information on the chromosomes and in the Insect Traits Key to complete
Data Table 2.
Data Table 2
Trait
Homozygous or
Genotype
Heterozygous
Dominant
or
Recessive
Phenotype
Head size
Chromosome
Pair 1
Eye color
Antennae
Thorax size
Chromosome
Pair 2
Wing color
Wing length
Leg length
Chromosome
Pair 3
Body color*
Abdomen size
Chromosome
Pair 4
Sex
Hemizygous
Not Applicable
* Body color refers to antennae, head, thorax, abdomen, and legs.
Insect Parts
Now that you have the phenotype of your offspring, draw the fly by tracing and then coloring the correct
Insect Parts in the box on the next page.
Insect Parts
Now that you have the phenotype of your offspring, draw the fly by tracing and then coloring the correct
Insect Parts in the box below.
Insect Parts
Use the following insect parts to trace your infant offspring.
Antennae
Abdomen
Abdomen
Thorax
Thorax