Gene Decoder Worksheet Gene Decoder
Station 2: Vocabulary Match-Up
Subject: Genetics
Date:
Lab Technician Name:
1
Vocabulary Match-Up
Match each genetic term to its scientific definition by writing the correct letter on the line.
____
Allele
____
Dominant
____
Recessive
____
Homozygous
____
Heterozygous
____
Genotype
____
Phenotype
A.
The observable physical traits or appearance of an organism.
B.
Having two different alleles for a specific gene (e.g., Bb).
C.
An allele that is only expressed when two copies are present.
D.
The specific genetic makeup or combination of alleles of an organism.
E.
An allele that is always expressed if present, masking others.
F.
One of two or more alternative versions of a specific gene.
G.
Having two identical alleles for a specific gene (e.g., BB or bb).
2
The Comparison Lab
Choose two pairs from the list below and explain the key difference between them in your own words.
Pair Selection: __________________________________________
Pair Selection: __________________________________________
Code Breaker Extension
Scenario: You are studying a pea plant with the genotype Tt.
What is the genotype?
What is the phenotype (if Tall is dominant)?
Gene Decoder Answer Key Gene Decoder Key
Station 2: Vocabulary Match-Up - Teacher Guide
Subject: Genetics
1
Vocabulary Match-Up
F
Allele
E
Dominant
C
Recessive
G
Homozygous
B
Heterozygous
D
Genotype
A
Phenotype
A.
The observable physical traits or appearance of an organism.
B.
Having two different alleles for a specific gene (e.g., Bb).
C.
An allele that is only expressed when two copies are present.
D.
The specific genetic makeup or combination of alleles of an organism.
E.
An allele that is always expressed if present, masking others.
F.
One of two or more alternative versions of a specific gene.
G.
Having two identical alleles for a specific gene (e.g., BB or bb).
2
The Comparison Lab (Sample Answers)
Genotype vs Phenotype
"Genotype is the actual letters (DNA code) like BB, while phenotype is what you actually see with your eyes, like blue eyes."
Dominant vs Recessive
"Dominant alleles are like the loudest person in the room—they show up even if there's only one. Recessive alleles are shy; they only show up if there are two of them together."
Homozygous vs Heterozygous
"Homozygous means 'same' (BB or bb), while heterozygous means 'different' alleles (Bb)."
Extension Key
Scenario: Genotype Tt.
What is the genotype?
Tt (Heterozygous)
What is the phenotype?
Tall
Gene Decoder Self Check Self-Check Card
Gene Decoder Station
Check your work against the official code!
1. Match-Up Key
Allele: F
Dominant: E
Recessive: C
Homozygous: G
Heterozygous: B
Genotype: D
Phenotype: A
2. Comparison Checklist
Did your explanation cover these main ideas?
Genotype vs Phenotype: Mentioned letters/DNA (Genotype) vs physical appearance (Phenotype).
Dominant vs Recessive: Noted that dominant hides recessive traits unless there are two recessives.
Homozygous vs Heterozygous: Mentioned "same" alleles (Homo) vs "different" alleles (Hetero).
3. Extension Check
Genotype
Tt
Phenotype
Tall
Done? Clean up the station for the next team!
Fur Color Challenge Worksheet Fur Color Challenge
Station 3: Monohybrid Cross Practice
Subject: Genetics
Date:
Lab Technician Name:
Observation Notes
In laboratory mice, black fur (B) is dominant to tan fur (b). A heterozygous male is crossed with a tan female.
1
Parent Genotypes
Male:
Female:
2
Punnett Square
__ __
__ __
3
Analysis Results
Genotypic Ratio
(List genotypes and their counts/percentages)
Phenotypic Ratio
(List physical traits and their counts/percentages)
Probability of Tan Offspring
?%
Final Summary for Records
Offspring Genotypes:
Offspring Phenotypes:
Fur Color Challenge Answer Key Fur Color Challenge Key
Station 3: Monohybrid Cross - Teacher Key
Subject: Genetics
Black (B) dominant to Tan (b). Heterozygous male (Bb) crossed with tan female (bb).
1
Parent Genotypes
Male:
Bb
Female:
bb
2
Punnett Square
B b
b b
Bb
bb
Bb
bb
3
Analysis Results
Genotypic Ratio
1 Bb : 1 bb (or 2:2)
50% Heterozygous, 50% Homozygous Recessive
Phenotypic Ratio
1 Black : 1 Tan (or 2:2)
50% Black, 50% Tan
Probability of Tan Offspring
50%
Final Summary Keys
Offspring Genotypes:
Bb, bb
Offspring Phenotypes:
Black, Tan
Fur Color Challenge Self Check Self-Check Card
Fur Color Station
Check your results for the mouse cross!
1. Parent Genotypes
Male
Bb
Female
bb
2. Punnett Square Result
B b
b b
Bb
bb
Bb
bb
3. Final Stats
Genotypes
1 Bb : 1 bb
Phenotypes
1 Black : 1 Tan
Tan Probability 50%
Everything match? Excellent lab work!
Dihybrid Duel Worksheet Dihybrid Duel
Station 4: Advanced Inheritance Challenge
Subject: Genetics
Date:
Lab Technician Name:
Field Observations: Pea Plants
Trait 1: Height
T = Tall (Dominant)t = Short (Recessive)
Trait 2: Flower Color
Y = Yellow (Dominant)y = White (Recessive)
Cross Request: Ttyy × TTYy
1
Gamete Formation
List all possible allele combinations each parent can pass to their offspring.
Parent 1 (Ttyy)
Parent 2 (TTYy)
2
16-Square Dihybrid Grid
____________
____________
3
Phenotype Target
What percentage of the offspring are expected to be Tall with White flowers ?
4
Independent Assortment
Explain why plant height doesn't determine flower color:
Dihybrid Duel Answer Key Dihybrid Duel Key
Station 4: Advanced Inheritance - Teacher Answer Key
Subject: Genetics
1
Gamete Formation Key
Parent 1 (Ttyy)
Ty
Ty
ty
ty
Parent 2 (TTYy)
TY
Ty
TY
Ty
2
Completed Grid Key
TYTyTYTy
TyTytyty
TTYy
TTyy
TTYy
TTyy
TTYy
TTyy
TTYy
TTyy
TtYy
Ttyy
TtYy
Ttyy
TtYy
Ttyy
TtYy
Ttyy
3
Target Key
Percentage of offspring that are Tall with White flowers :
50%
(8 out of 16 squares are TTyy or Ttyy)
4
Explanation Key
"According to Mendel's Law of Independent Assortment, different traits are inherited independently of one another. Alleles for height and flower color are on different chromosomes and separate randomly during gamete formation."
Dihybrid Duel Self Check Self-Check Card
Dihybrid Challenge
Station 4: Verify Your Pea Plant Predictions
1. Gamete Combos
Parent 1 (Ttyy)
Ty Ty ty ty
Parent 2 (TTYy)
TY Ty TY Ty
2. Grid Summary
Row 1
TTYy, TTyy, TTYy, TTyy
Row 2
TTYy, TTyy, TTYy, TTyy
Row 3
TtYy, Ttyy, TtYy, Ttyy
Row 4
TtYy, Ttyy, TtYy, Ttyy
3. Tall & White Offspring?
Counted 8 squares out of 16...
50%
Independent Assortment Check
Did you mention that genes are on different chromosomes and separate randomly?
Remember to clean your lab station before moving on!
