Name: _______________________________________ Period: _______
Genetics Study Guide
Biology
Genetics Study Guide
I.
Vocabulary
Match the following vocabulary words to their definitions by writing the corresponding letter
on the line.
___1. The branch of biology that studies inheritance.
___2. A physical or behavioral characteristics that is
passed from parents to offspring.
___3. The part of the DNA that determines traits.
___4. The type of cell division that creates 2
identical cells.
___5. The type of cell division that creates 4
reproductive cells.
A.
B.
C.
D.
E.
Gene
Genetics
Meiosis
Mitosis
Trait
___6.
___7.
___8.
___9.
The various forms a gene that exist.
The allele that shows.
The allele that is hidden.
The combination of alleles that an
organism inherits.
__10. The trait that you see based on an
individual’s genotype.
F. Allele
G. Dominant allele
H. Genotype
I. Phenotype
J. Recessive allele
___11. Genotype that results from two of the
same allele.
___12. Genotype that results from two different
alleles.
___13. Type of inheritance in which the heterozygote
shows both alleles equally and separately.
___14. Type of inheritance in which the heterozygote’s
phenotype is a blend of the two alleles.
___15. Type of inheritance where there is more than
two alleles for a particular trait.
___16. Trait that is determined by a gene located on the
X or Y chromosome.
___17. Trait that is determined by the combination of two
or more genes.
K. Codominance
L. Heterozygous
M. Homozygous
N. Incomplete dominance
O. Multiple alleles
P. Polygenic trait
Q. Sex-linked trait
Name: _______________________________________ Period: _______
Genetics Study Guide
Biology
II.
Genetic Cross Problems
Solve the following genetic crosses by completing Punnett squares and answering the questions. You
must show all work!
Simple Punnett Squares
18. In humans, brown eyes (B) are dominant to blue eyes (b). If you cross a blue-eyed female with a
heterozygous brown-eyed man, what is the probability they will have a child with blue eyes?
19. In cats, a fluffy tail (F) is dominant to a smooth tail (f). If a heterozygous fluffy-tailed cat is crossed
with a homozygous fluffy-tailed cat, what is the probability they will have an offspring with a smooth
tail?
Complex Genetic Problems
20. In chickens, the alleles for black (B) and white (W) feathers are co-dominant. The heterozygous
chickens are checkered. If a checkered chicken is crossed with a black chicken, what is the probability
they will have an offspring that is white?
Name: _______________________________________ Period: _______
Genetics Study Guide
Biology
21. In raccoons, the thickness of the rings on the tail is inherited by incomplete dominance. Raccoons
can have thick-ringed tailed (TT); skinny-ringed tails (SS) or medium-ringed tails (TS). If two mediumringed raccoons are crossed, what is the probability that their offspring will have skinny-ringed tails?
22. In humans, color-blindness is a trait inherited on the X chromosome. If a man who is color-blind is
crossed with a woman who is heterozygous for color-blindness, what is the probability that they will
have a child who is colorblind?
23. The height of a giraffe is determined by a combination of 5 genes. The giraffe will begin as 4 m in
height and gain 0.5 m for each dominant allele it inherits. If a giraffe is GgGGGgggGg, how tall will that
giraffe be?
24. Explain why traits such as skin color, weight, height, and eye color are found in such wide varieties.
Name: _______________________________________ Period: _______
Genetics Study Guide
Biology
25. Explain why you can’t always just use a Punnett square to determine the outcome of a particular
cross.