Download Section 3-2C

Name ______________________________ Class ___________________ Date __________________
Skills Worksheet
Section 3-2 (C):Traits and
Inheritance
_____ 1. What ratio did Mendel find for dominant to recessive traits?
a. 1 to 1
b. 2 to 1
c. 3 to 1
d. 4 to 1
A GREAT IDEA
_____ 2. What are the instructions for an inherited trait?
a. alleles
b. phenotype
c. albinism
d. genes
_____ 3. Two forms of a gene, one from each parent, are called
a. alleles.
b. phenotypes.
c. albinism.
d. genes.
_____ 4. When gene pairs are written, the dominant allele has a(n)
a. D in front of it.
b. capital letter.
c. bold letter.
d. underlined letter.
_____ 5. The genotype Pp can also be written
a. pP
b. pp
c. PP
d. Ppp
_____ 6. When purple is dominant, the white offspring of purple and white
parents will be
a. pP
b. pp
c. PP
d. Ppp
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Name ______________________________ Class ___________________ Date __________________
Directed Reading A continued
Match the correct description with the correct term. Write the letter in the space
provided.
_____ 7. used to organize possible offspring
combinations
a. phenotype
b. heterozygous
_____ 8. an organism’s appearance
_____ 9. a plant with one dominant and one recessive
gene
_____ 10. condition that causes colorless hair, skin, and
eyes
_____ 11. a plant with either two dominant or two
recessive genes
c. genotype
d. homozygous
e. genes
f. albinism
g. Punnett square
_____ 12. genetic makeup formed from both inherited
alleles together
_____ 13. instructions for traits passed to offspring from parents
14. Look at the Punnett square on the left. What genotype do all of the offspring
have?
_______________________________________________________________
16. Look at the Punnett square on the right. Which two genotypes contain a
dominant allele?
_______________________________________________________________
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Name ______________________________ Class ___________________ Date __________________
Directed Reading A continued
WHAT ARE THE CHANCES?
_____ 18. The mathematical chance that something can happen is called
a. genotype.
b. albinism.
c. probability.
d. trait.
20. Why are the traits that Mendel studied in pea plants easy to predict?
_______________________________________________________________
_______________________________________________________________
MORE ABOUT TRAITS
21. When each allele has its own degree of influence, it is known
as______________________.
22. How is a snapdragon an example of incomplete dominance?
_______________________________________________________________
_______________________________________________________________
23. Sometimes one gene can influence more than one ______________________.
24. Besides genes, what else can have an influence on traits?
_______________________________________________________________
_______________________________________________________________
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Name ______________________________ Class ___________________ Date __________________
Skills Worksheet
Section 3-2 (C) Reinforcement
Dimples and DNA
Complete this worksheet after you finish reading the section “Traits and
Inheritance.”
In humans, dimpled cheeks are a dominant trait, with a genotype of DD or Dd.
Nondimpled cheeks are a recessive trait, with a genotype of dd.
1. Imagine that Parent A, with the genotype DD, has dimpled cheeks. Parent B
has the genotype dd and does not have dimpled cheeks.
The Punnett square below diagrams the cross between Parent A and Parent B.
Complete the Punnett square. The first square has been done for you.
2. A Punnett square shows what genotypes are possible for the offspring of a
certain cross. What genotypes are possible for the offspring of Parent A and
Parent B?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
3. Each of the four squares of a Punnett square represents a 25 percent
probability that the offspring will have that particular genotype. What is the
probability that the offspring of Parent A and Parent B will have dimpled
cheeks?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
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Name ______________________________ Class ___________________ Date __________________
Reinforcement continued
4. Parent X, with the genotype Dd, has dimpled cheeks. Parent Y also has the
genotype Dd and has dimpled cheeks as well. To find out what their offspring
might look like, complete the Punnett square below.
5. What is the probability that the offspring of Parent X and Parent Y will have
each of the following genotypes?
DD: ___________________________________________________________
Dd: ____________________________________________________________
dd: ____________________________________________________________
6. What is the probability that the offspring of Parent X and Parent Y will have
nondimpled cheeks?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
7. What is the probability that the offspring of Parent X and Parent Y will have
dimpled cheeks? (Remember that there are two genotypes that can produce
dimpled cheeks.)
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
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Name ______________________________ Class ___________________ Date __________________
Skills Worksheet
Section 3-2 (C) Review
UNDERSTANDING KEY IDEAS
3.Use a Punnett square to determine the possible genotypes of the offspring of a
BB x Bb cross.
a. all BB
c. BB, Bb, bb
b. BB, Bb
d. all bb
4. How are genes and alleles related to genotype and phenotype?
_______________________________________________________________
_______________________________________________________________
5. Describe three exceptions to Mendel’s observations.
_______________________________________________________________
_______________________________________________________________
MATH SKILLS
6. What is the probability of rolling a five on one die three times in a row? Show
your work below.
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Name ______________________________ Class ___________________ Date __________________
Section Review continued
CRITICAL THINKING
7. .Applying Concepts The allele for a cleft chin, C, is dominant among humans.
What are the results of a cross between parents with genotypes Cc and cc?
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
_______________________________________________________________
INTERPRETING GRAPHICS
The Punnett Square below shows the alleles for full color in rabbits. Black fur, B,
is dominant over white fur, b.
8. Given the combinations shown, what are the genotypes of the parents?
_______________________________________________________________
_______________________________________________________________
9. If black fur had incomplete dominance over white fur, what color would the
offspring be?
_______________________________________________________________
_______________________________________________________________
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Name ______________________________ Class ___________________ Date __________________
Assessment
Section 3-2 (C) Quiz
Section: Traits and Inheritance
Match the correct description with the correct term. Write the letter in the space
provided.
_____ 1. when one trait is not completely
dominant over another
a. phenotype
b. genotype
_____ 2. a way to organize possible offspring
combinations
c. incomplete dominance
_____ 3. an organism’s appearance
d. Punnett square
_____ 4. the entire genetic makeup of an organism
e. probability
_____ 5. the mathematical chance that something
will happen
Write the letter of the correct answer in the space provided.
_____ 6. Each parent gives one set of these to the offspring.
a. genes
b. alleles
c. phenotypes
d. meiosis
_____ 7. A plant with two dominant OR two recessive alleles is said to be
a. heterozygous.
b. cross-pollinating.
c. homozygous.
d. true breeding.
_____ 8. Which one of the following statements is NOT true?
a. One gene can influence many traits.
b. Several genes can influence a single trait.
c. The environment can have an influence on traits.
d. Genes are the only influence on traits.
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