NAME __________________________________
Mystery Organism – Monohybrid Punnett Squares
INSTRUCTIONS: You will be creating your own imaginary organisms through the selections you choose from the
following options.
NOSE SIZE
FINGERNAILS/CLAWS
Homozygous
Dominant Short Nose
Homozygous
Dominant Nails/Claws
Heterozygous Short
Nose
Homozygous
Recessive Long Nose
Heterozygous
Nails/Claws
Homozygous
Recessive No
Nails/Claws
TAIL/NO TAIL
HAIR/FUR
COLOR
Homozygous Homozygous
Dominant
Dominant
Tail
Black
Heterozygous Heterozygous
Tail
Black
Homozygous Homozygous
Recessive No Recessive Red
Tail
LARGE/SMALL
BODY SIZE
Homozygous
Dominant
Large
Heterozygous
Large
Homozygous
Recessive
Small
EARS/NO EARS
Homozygous
Dominant Ears
Heterozygous
Ears
Homozygous
Recessive No
Ears
Your organism needs to have at least one (1) homozygous dominant, one (1) heterozygous, and one (1) homozygous
recessive trait. My organism has the following traits: Be sure to include if the trait is homozygous dominant,
heterozygous, or homozygous recessive.
NOSE SIZE
FINGERNAILS/CLAWS
TAIL/NO TAIL
HAIR/FUR
COLOR
LARGE/SMALL
BODY SIZE
EARS/NO EARS
You are to develop one other trait in the box below for your organism. Put the trait information in the box below.
TRAIT
HOMOZYGOUS DOMINANT
HETEROZYGOUS
HOMOZYGOUS RECESSIVE
Draw and color your organism below:
Now that you have created your imaginary organism from selecting your traits for it, you will be doing some Punnett
Square crosses with your organism to see what types of F1 & F2 offspring you will get.
Ex: Trait: Claws
Dominant Letter: C
Recessive Letter: c
Trait: ___________________________ Dominant Letter: _________________ Recessive Letter: _______________
PUNNETT SQUARE #1:
P Generation: Using the trait that you chose above, cross a homozygous dominant parent with a homozygous recessive
parent.
These offspring
are the F1
generation
Genotype for F1 generation: __________________________________
Phenotype for F1 generation: ___________________________________
PUNNETT SQUARE #2:
F1 Generation: Using the F1 Generation from the cross above make a cross between 2 of the offspring.
These offspring
are the F2
generation
Genotype for F2 generation: __________________________________
Phenotype for F2 generation: ___________________________________
PUNNETT SQUARE #3:
Now choose a different trait other than the one above.
Trait: ___________________________ Dominant Letter: _________________ Recessive Letter: _______________
Cross a homozygous recessive parent with a
heterozygous parent
Parents: _____________ X _____________
Cross two (2) heterozygous parents
Parents:
_____________ X _____________
Genotype for F1 generation: _______________________
Genotype for F1 generation: _____________________
Phenotype for F1 generation: _______________________
Phenotype for F1 generation: _____________________