Download Changes in DNA and results of changes

Components of DNA and how DNA
relates to traits
1. The structures marked 3 in the
diagram are responsible for –
a. Absorbing oxygen
b. Carrying genetic codes
c. Lining up amino acids
d. Serving as an anticodon
2. Why will knowledge of the human
genome enable scientists to better understand proteins involved in
human diseases?
a. DNA contains the information used to make proteins.
b. Nucleic acid molecules have shapes similar to those of proteins
c. The bases that make up DNA are also present in RNA.
d. Chromosomes can combine to form proteins.
3. Which of the following features of DNA is most important in
determining the phenotype of an organism?
a. The direction of the helical twist
b. The number of deoxyribose sugars
c. The sequence of nitrogen bases
d. The strength of hydrogen bonds
4. A particular strand of DNA has the base sequence ATT-CCG. What
is the base sequence of the complementary strand?
a. ATT-CCG
b. TAA-GGC
c. CCG-TTA
d. TAT-CGC
(1 – B)
(2 – A)
(3 – C)
(4 – B)
Changes in DNA and results of changes
1. A DNA segment is changed from AATTAG to AAATAG . This is
a(n)
a. Frame shift mutation
b. Point mutation
c. Inversion
d. Deletion
2. What type of mutation has
occurred in the figure?
a. Point mutation
b. Frame shift
c. Lethal
d. Protein
3. What will be the result of the preceding mutation?
a. It will have no effect on protein function
b. Only one amino acid will change
c. Nearly every amino acid in the protein will be changed
d. The organism will die
4. A strand of DNA with the sequence AAC AAG CCC undergoes a
mutation, is changed to CAC AAG CCC. How will this mutation affect
the amino acid sequence?
a. One amino acid will change
b. Two amino acids will change
c. All of the amino acids will change
d. The amino acids will remain the same
5. Most mutations
a. have no effect on an organism.
b. are fatal to an organism.
c. are helpful to an organism.
d. are harmful to an organism.
(1-B, 2-B, 3-C, 4-A, 5-A)
Genetics – Predict outcomes of crosses
1. In humans, freckles are encoded by a dominant allele. An individual
woman is heterozygous for freckles. According to the law of segregation,
which of the following would apply to a child of this woman?
A. The child must inherit the dominant allele for freckles.
B. The child must inherit the recessive allele for freckles.
C. The child has an equal chance of inheriting the dominant allele or
the recessive allele for freckles from her mother.
D. The child has a greater chance of inheriting the dominant allele
than the recessive allele for freckles from her mother.
2. The illustration below shows two adult
rabbits and their offspring.
In rabbits, the allele for spots (R) is
dominant to the allele for solid color (r).
What is the most likely genotype of the
parent rabbits in the illustration?
A. rrrr
B. Rrrr
C. RrRr
D. RRrr
3. In pea plants, the allele for purple flowers (P) is dominant to the allele
for white flowers (p). A plant that is heterozygous for purple flowers is
crossed with a plant with white flowers. What percentage of the offspring
plants are expected to have purple flowers?
A. 25%
B. 50%
C. 75%
D. 100%
4. In a certain variety of chicken, some offspring have a feather pattern
that is black-and-white checkered. Chickens with this checkered feather
pattern result from the cross of a black chicken with a white chicken.
Which of the following types of inheritance is most likely responsible for the
checkered feather pattern?
A. codominant
B. dominant
C. polygenic
D. sex-linked
5. In sheep, the allele for white wool (W) is dominant, and the allele for
black wool (w) is recessive. A farmer has mated two Suffolk sheep for a
few years. These matings have resulted in six offspring, four with white
wool and two with black wool. One parent has white wool and the other has
black wool.
Which of the following could be the genotypes of the parent sheep?
A. WW and Ww
B. WW and ww
C. Ww and Ww
D.Ww and ww
6. Female cattle that have white coats are crossed with male cattle that
have red coats. Both male and female offspring have roan coats, which are
coats with both red hairs and white hairs.
Which of the following best describes the genetics of coat color in the
cattle?
A. The red and white alleles are sex-linked.
B. The red and white alleles are codominant.
C. The red allele is recessive to the white allele.
D. The red allele is dominant to the white allele.
7. A partial Punnett square is shown below.
Which of the following statements describes the parental genotypes that
would result in this Punnett square?
A. Both parents are heterozygous.
B. Both parents are homozygous dominant.
C. One parent is homozygous recessive and the other parent is
heterozygous.
D. One parent is homozygous dominant and the other parent is
heterozygous.
Key
1. C
2. B
3. B
4. A
5. D
6. B
7. D