Download 3/1/2013 - Biloxi Public Schools

Genetics DQ 2014-2015
Name: _______________________________
1. The diagram represents a cross between two pea plants. In pea plants, the allele
for round seeds (R) is dominant to the allele for oval seeds (r). In a cross between
the two plants above, what percentage of the offspring will have round seeds?
A 100%
B 75%
C 50%
D 25%
Justification---_____________________________________________
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2. What ratio of the offspring from the cross shown will be homozygous recessive for
the trait of tallness? A 0 in 4
B 1 in 4
C 2 in 4
D 4 in 4
Justification---_____________________________________________
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3.
A
B
C
D
The phenotype of an animal depends MOST directly on ––
how the genes of the animal are expressed.
the metabolic rate of the animal.
the source of the animal’s food.
how many cells are in the animal’s body.
Justification---_______________________________________________________________________________
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4. Glossy leaves are smooth and shiny. What percent of offspring from the cross
shown above will have glossy leaves?
A 0%
B 25%
C 50%
D 100%
Justification---_____________________________________________
_________________________________________________________
5. In pea plants, “tall” is dominant to “short.” To determine if a tall pea
plant is heterozygous or homozygous for tallness, it should be crossed
with a plant that is known to be —
A purebred tall.
B purebred short.
C heterozygous tall.
D heterozygous
short.
Justification---_______________________________________________________________________________
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6. Gregor Mendel pioneered studies of heredity in the 1800s. He believed that parent
organisms could transmit any random combination of characteristics to their
offspring. Today, however, scientists know that some of the parents’ characteristics
are inherited together as a group because —
A certain genes attract one another and then stay together.
B many genes are located together on the same chromosome.
C pairs of chromosomes are joined together like the two sides of a zipper.
D the chromosomes from one parent are dominant and those from the other are recessive.
Justification---_______________________________________________________________________________
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Genetics DQ 2014-2015
Name: _______________________________
7. In pea plants, the trait for being tall (T) is dominant over the trait for being short (t).
What is the expected phenotypic outcome of the F1 generation in the cross shown above?
A 100% short B 50% tall
C 75% short
D 100% tall
Justification---___________________________________________________________
_______________________________________________________________________
8. Sickle cell anemia is a disease that occurs when an individual receives a recessive
allele for sickle cell from each parent. Assume that a woman who is a carrier for sickle
cell marries a man who is free of disease. What are the chances of this couple having a
child with sickle cell anemia?
A 0%
B 25%
C 50%
D 100%
Justification---______________________________________________________________________________
__________________________________________________________________________________________
9. Botanists cross a heterozygous (Pp) plant having purple flowers with a homozygous (pp) plant having white
flowers. About what percentage of the offspring will have purple flowers?
A 0%
B 25%
C 50%
D 75%
Justification---______________________________________________________________________________
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10. In certain breeds of dogs, deafness is due to a recessive allele (d) of a particular gene, and normal
hearing is due to its dominant allele (D). What percentage of the offspring of a normal heterozygous (Dd)
dog and a deaf dog (dd) would be expected to have normal hearing?
A 0%
B 25%
C 50%
D 100%
Justification---______________________________________________________________________________
__________________________________________________________________________________________
11. Genetic engineering has produced goats whose milk contains proteins that can be used as medicines.
This effect was produced by ---A mixing foreign genes into the milk.
B injecting foreign genes into the goats’ udders.
C inserting foreign genes into fertilized goat eggs.
D genetically modifying the nutritional needs of the goats’ offspring.
Justification---______________________________________________________________________________
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12. A new variety of tomato is better tasting and can be stored longer than other tomato varieties. This new tomato is
produced by placing additional gene segments into the cells of the tomato plant. This process is known as
A. genetic engineering
B. selective breeding
C. natural selection
D. sexual reproduction
Justification---______________________________________________________________________________
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