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NEW BIO 1050 EXAM 3 PRACTICE Q&A GRADED A+
TESTED AND APPROVED NEWLY MODIFIED!!!
When crossing-over occurs, _______________ genes usually stay together. a.
multi-allelic
b. sex-linked
c. pleiotropic
d. independently assorting
e. linked -- ANSWER--e.
linked
Albinism (lack of skin and hair pigmentation) is caused by a recessive autosomal allele. A
woman and man, both normally pigmented, have an albino child together. For this trait, what
is the genotype of the albino child?
a. heterozygous
b. homozygous recessive
c. homozygous dominant
d. It is unknown, because not enough information is provided.
e. It depends on the sex of the child. -- ANSWER--b.
homozygous recessive
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,A true-breeding red rose is repeatedly mated with a true-breeding white rose, and all of their
offspring are red. If two of these red offspring are mated, what percentage of their offspring
will be red?
a. 60%
b. 100%
c. 25%
d. 50%
e. 75% -- ANSWER--e.
75%
In asexual reproduction, daughter cells inherit their DNA from ____________.
a. two separate parents
b. a single parent
c. a single offspring
d. multiple offspring
e.None of the above is correct; in asexual reproduction, the DNA is not inherited. --
ANSWER--b.
a single parent
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, Page 3 of 66
Tay-Sachs, which is a recessive lethal disease, results only when individuals possess two
copies of the disease-causing allele. Which of the following statements is TRUE about this
disease?
a.
Heterozygous individuals may pass on their copy of the disease-causing allele to offspring. b.
Heterozygous individuals only pass on the dominant copy of the allele to offspring. c.
Heterozygous individuals are more fit than homozygous dominant individuals, so eventually,
there will only be heterozygotes in the population. d.
All cases of this disease must be caused by new mutations. e.
None of the above. -- ANSWER--a.
Heterozygous individuals may pass on their copy of the disease-causing allele to offspring.
Some genes, such as the human ABO blood groups, have more than two alleles. For these
genes:
a. some individuals can be triply heterozygous.
b. natural selection cannot alter the allele frequencies.
c. a greater proportion of the individuals must be heterozygous than homozygous.
d. normal dominance relationships are not possible.
e. individuals can only possess two alleles. -- ANSWER--e.
individuals can only possess two alleles.
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, In the case of Mendel's peas, a single gene determined the height of the plant; however, in
humans, adult height is influenced by many genes. A trait such as human height is said to be:
a. codominant.
b. polygenic.
c. multi-allelic.
d. incompletely dominant.
e. pleiotropic. -- ANSWER--b.
polygenic
Bacteria reproduce asexually, whereas most plants and animals reproduce sexually. Which is
the better method?
a. Neither method is better—each is effective in different environments for different kinds of
organisms.
b. Sexual reproduction is the better method, because it produces more variation.
c. Sexual reproduction is the better method, because more plants and animals than bacteria
are present.
d. Asexual reproduction is the better method, because more bacteria than plants and animals
are present.
e. Asexual reproduction is better, because binary fission is more efficient. -- ANSWER--a.
Neither method is better—each is effective in different environments for different kinds of
organisms.
Phenotypes are generally a product of:
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NEW BIO 1050 EXAM 3 PRACTICE Q&A GRADED A+
TESTED AND APPROVED NEWLY MODIFIED!!!
When crossing-over occurs, _______________ genes usually stay together. a.
multi-allelic
b. sex-linked
c. pleiotropic
d. independently assorting
e. linked -- ANSWER--e.
linked
Albinism (lack of skin and hair pigmentation) is caused by a recessive autosomal allele. A
woman and man, both normally pigmented, have an albino child together. For this trait, what
is the genotype of the albino child?
a. heterozygous
b. homozygous recessive
c. homozygous dominant
d. It is unknown, because not enough information is provided.
e. It depends on the sex of the child. -- ANSWER--b.
homozygous recessive
Page | 1
,A true-breeding red rose is repeatedly mated with a true-breeding white rose, and all of their
offspring are red. If two of these red offspring are mated, what percentage of their offspring
will be red?
a. 60%
b. 100%
c. 25%
d. 50%
e. 75% -- ANSWER--e.
75%
In asexual reproduction, daughter cells inherit their DNA from ____________.
a. two separate parents
b. a single parent
c. a single offspring
d. multiple offspring
e.None of the above is correct; in asexual reproduction, the DNA is not inherited. --
ANSWER--b.
a single parent
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, Page 3 of 66
Tay-Sachs, which is a recessive lethal disease, results only when individuals possess two
copies of the disease-causing allele. Which of the following statements is TRUE about this
disease?
a.
Heterozygous individuals may pass on their copy of the disease-causing allele to offspring. b.
Heterozygous individuals only pass on the dominant copy of the allele to offspring. c.
Heterozygous individuals are more fit than homozygous dominant individuals, so eventually,
there will only be heterozygotes in the population. d.
All cases of this disease must be caused by new mutations. e.
None of the above. -- ANSWER--a.
Heterozygous individuals may pass on their copy of the disease-causing allele to offspring.
Some genes, such as the human ABO blood groups, have more than two alleles. For these
genes:
a. some individuals can be triply heterozygous.
b. natural selection cannot alter the allele frequencies.
c. a greater proportion of the individuals must be heterozygous than homozygous.
d. normal dominance relationships are not possible.
e. individuals can only possess two alleles. -- ANSWER--e.
individuals can only possess two alleles.
Page | 3
, In the case of Mendel's peas, a single gene determined the height of the plant; however, in
humans, adult height is influenced by many genes. A trait such as human height is said to be:
a. codominant.
b. polygenic.
c. multi-allelic.
d. incompletely dominant.
e. pleiotropic. -- ANSWER--b.
polygenic
Bacteria reproduce asexually, whereas most plants and animals reproduce sexually. Which is
the better method?
a. Neither method is better—each is effective in different environments for different kinds of
organisms.
b. Sexual reproduction is the better method, because it produces more variation.
c. Sexual reproduction is the better method, because more plants and animals than bacteria
are present.
d. Asexual reproduction is the better method, because more bacteria than plants and animals
are present.
e. Asexual reproduction is better, because binary fission is more efficient. -- ANSWER--a.
Neither method is better—each is effective in different environments for different kinds of
organisms.
Phenotypes are generally a product of:
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