Variation of Traits
1
Meiosis contributes to genetic variation due to which of the
following characteristics of the process?
A
The process begins with one diploid cell containing two
copies of each chromosome.
B
Gametes that contain half the genetic information are
formed.
C
Homologous chromosomes move to opposite sides of
the cell to form new nuclei.
D
When homologous chromosomes split, sections of
chromosomes can switch places.
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Variation of Traits
2
The gene for tallness (T) in a pea plant is dominant over the
gene for shortness (t). In a cross between two heterozygous
parent pea plants, we can predict that what percentage of the
offspring will be tall?
A
100%
B
50%
C
75%
D
25%
2
Variation of Traits
3
Which of the following provides evidence for the idea that
certain environmental factors can alter DNA and cause
mutations?
A
The processes responsible for cellular growth and
repair are more efficient when an individual receives
adequate nutrition.
B
Characteristics of certain individuals within a
population make them more or less likely to survive an
environmental change.
C
Skin cancer is more likely to develop in individuals who
experience excessive exposure to sunlight.
D
Errors that occur during mitosis can sometimes provide
a benefit to the individual but are more likely neutral.
3
Variation of Traits
4
An investigation involves a species of microorganisms. One population
is exposed to radiation and the other population is shielded from
radiation. The population exposed to radiation exhibits a mutation while
the other population exhibits no mutation.
Both populations are then allowed to reproduce under normal
conditions. Thirty generations later, the descendants of the population
exposed to radiation still exhibit the mutation. Why can’t this
observation be used to support the claim that the exposure to radiation
did not cause the mutation?
A
Only mutations that are beneficial are passed on to successive
generations.
B
Neither population had the mutation before exposure to
radiation.
C
Once a mutation is present in the genome, it is inherited by
offspring.
D
Some mutations are the result of errors in the transcribing of
genes.
4
Variation of Traits
5
The ability for people to roll their tongue is dominant to people
who cannot. If a tongue roller and a non-tongue roller were
crossed, the highest percentage of potential non-tongue roller
offspring would be which of the following?
A
50%
B
0%
C
100%
D
25%
5