Power Study:
Probability and
Genetics Quiz
For Mrs. Schworer
Terms
Match the terms that goes together
 Heterozygous
 Trait
 Phenotype
 Hybrid
 Homozygous
 Purebred
 Phenotype
 Allele
Definitions
 Phenotype - the set of observable characteristics of an individual
resulting from the interaction of its genotype with the environment. (trait)
 Genotype - he genetic constitution of an individual organism. (Allele)
 Homozygous - having the two genes that are the same. (Purebred)
 Heterozygous – having two genes that are different. (Hybrid)
Heterozygous or
Homozygous
Classify each of the following gene pairs as heterozygous
or homozygous
Homozygous
RR _________
Homozygous
ff __________
Tt Heterozygous
__________
Heterozygous
Ll __________
TRAIT
DOMINANT GENE
RECESSIVE GENE
Hair Color
Brown - B
Blonde - b
Widows Peak
With Widows Peak - W
Without Widows Peak - w
Dimples
With Dimples - D
Without Dimples - d
BB
Purebred brown hair color - _______
Ww
Hybrid with widows peak:______
Dd
Heterozygous with dimples: ______
bb
Homozygous blonde hair color: ______
Round eyes (R) are dominant to Oval eyes (r) in Mrs.
Schworer’s family. Give the PHENOTYPE for each of the
genotypes below.
Round eyes
 RR - ______________
Round eyes
 Rr - _______________
Oval eyes
 rr - _______________
Long nose – L
Short nose - l
 Donald Duck is heterozygous for a long nose. He recently married Daffy
Duck with homozygous for a stubby nose.
Ll
 Donald Duck (heterozygous for long nose) = __________
ll
 Daffy Duck (homozygous for stubby nose) = __________
COMPLETE THE PUNNETT SQUARE
L
l
l
Ll
ll
l
Ll
ll
50
Percentage for long nose? ______%
50
Percentage for stubby nose________%
What is Codominant?
 Codominance is ……
A. Codominance is when a heterozygous organism will
express or show both dominant alleles for a trait.
B. Codominance is when nothing is dominant.
C. Codominance is when a homozygous organism
will express or show both dominant alleles for a trait.
Codominance
 In horses theres is a codominance; (B) is the symbol for black, (W) is they
symbol for white, and (BW) is the symbol for black and white.
Cross a homozygous black male horse with a homozygous white female
horse.
B
B
W
BW
BW
W
BW
BW
Genotypes of offspring:
Phenotypes of offspring:
BW
______________________
Black and White
______________________
Multiple Alleles
 If Ryan has the blood type O and is married with Deanna who has the
blood type A, she would be homozygous for this blood type, what blood
A B
types could their children have? Remember to use I , I , and I for the
alleles.
i
i
IA
IA i
IA i
IA
IA i
IA i
A
The children would have blood type(s): ________________
Incomplete Dominance
 Bob the gardener is growing roses that come in the
colors red (RR), white(WW), and pink (RW).
 What would happen if Bob crossed a pink flower with a
red flower?
R
R
RR
W
RW
How many plants would be red?
50
___________%
How many plants would be white?
_________%
0
R
RR
RW
How many plants would be pink?
50
__________%
Continue to look over your
worksheets!
 Keep practicing past work and reviewing your terms!
 BEST OF LUCK! Take your time on the quiz and I know
you will all do great 