BIOLOGY PRAXIS QUESTIONS WITH VERIFIED
ACCURATE ANSWERS
Which of the following characteristics of a material found on the bark of a tree most
likely prove that the material is a living thing? - Answers -the material appears to
reproduce on its own
Given the DNA sequence 5' ATGCCCTCA 3', which of the following is the correct
complementary sequence of messenger RNA? - Answers -3' UACGGGAGU 5'
*RNA = uracil replaces thymine in DNA
According to evolutionary theory, which of the following individuals has the greatest
Darwinian fitness? - Answers -a woman who lives to be 80 yrs old, has 6 children and
30 grandchildren, and is in poor health most of her life
Darwinian fitness - Answers -largely defined by the ability to survive, reproduce, and
pass on one's genes
When the caribou migrate, the weaker ones often become the prey of wolves and other
carnivores. If the vegetation that the caribou eat is sparse for several consecutive years,
which of the following will most likely be true about the wolf population during the same
period? - Answers -the wolf population will initially increase because of an increase in
the wolves' food availability
Which TWO of the following are scientific theories? - Answers -evolutionary
adaptations arise by natural selection / the number of species in an isolated island-like
habitat is determined by an equilibrium between the rates of immigration and extinction
scientific theory - Answers -an explanation that is generally broad in scope, is
supported by a large body of evidence, and that can serve as the basis for new
hypothesis and experimentation
A diploid organism has the genotype AaBbCc for three loci, each of which is located on
a different chromosome. A normal gamete produced by this organism could have which
of the following genotypes? - Answers -AbC
Which of the following amino acids can contribute to the 3-dimensional structure of a
protein by forming covalent bonds with an identical amino acid in another part of the
protein? - Answers -contains SH
The sciatic nerve from a frog was isolated and placed into a nerve chamber. A recording
of an action potential was measured when the nerve was bathed in a solution that
, mimics the extracellular fluid typically surrounding a cell, and the nerve was stimulated.
The recording is shown above. If the toxin TTX, a potent sodium-channel blocker, is
added to the bathing solution and the nerve is stimulated using a stimulus of the same
strength, what will be the most likely change in the action potential? - Answers -the
action potential will not occur, because depolarization will not occur
Sea star wasting syndrome is decimating some populations of sea stars along the North
American Pacific coast. Sea stars are the only natural predator of sea urchins and
mussels in some portions of the ecosystem. Which of the following is most likely a
concern for scientists studying the ecosystem? - Answers -w/o sea stars, the sea
urchin and mussel populations will increase and eliminated other species in the
ecosystem
Which of the following statements regarding the water cycle is correct? - Answers -the
water cycle differs from other biogeochemical cycles because most water moves
through ecosystems by physical rather than chemical processes
The skeletal structures of the human arm and whale flipper (pectoral fin) are shown
above. The arm and flipper are examples of... - Answers -homologous structures
the various structures in different species having the same function but have evolved
separately - Answers -analogous structures
Which of the following is required to initiate transcription of a particular gene in
eukaryotic cells? - Answers -an RNA polymerase associates with transcription factors
bound to the gene's regulatory sequences
In a plant, undifferentiated cells that can divide throughout the life of the plant to enable
growth are found in which of the following? - Answers -meristem
Investigators have immunized a rabbit with substance P. They are studying the effect of
the immunization on production of anti-substance P antibodies over a 2-week period
following the immunization. Which of the following is the best hypothesis for the
experiment? - Answers -antibody production by the rabbit in response to substance P
will increase over a 2-week period
The evaporation of water through the stomata in plant leaves, which creates a negative
pressure and causes water to be absorbed into the plant through the roots. - Answers -
Transpiration
Which of the following conditions would cause the most rapid lowering of the water level
in the pipet? - Answers -increasing the light intensity
Aphids are small insects that can rest on the stems and leaves of plants and insert their
needlelike mouthpiece directly into the phloem of the plants. Which of the following is
ACCURATE ANSWERS
Which of the following characteristics of a material found on the bark of a tree most
likely prove that the material is a living thing? - Answers -the material appears to
reproduce on its own
Given the DNA sequence 5' ATGCCCTCA 3', which of the following is the correct
complementary sequence of messenger RNA? - Answers -3' UACGGGAGU 5'
*RNA = uracil replaces thymine in DNA
According to evolutionary theory, which of the following individuals has the greatest
Darwinian fitness? - Answers -a woman who lives to be 80 yrs old, has 6 children and
30 grandchildren, and is in poor health most of her life
Darwinian fitness - Answers -largely defined by the ability to survive, reproduce, and
pass on one's genes
When the caribou migrate, the weaker ones often become the prey of wolves and other
carnivores. If the vegetation that the caribou eat is sparse for several consecutive years,
which of the following will most likely be true about the wolf population during the same
period? - Answers -the wolf population will initially increase because of an increase in
the wolves' food availability
Which TWO of the following are scientific theories? - Answers -evolutionary
adaptations arise by natural selection / the number of species in an isolated island-like
habitat is determined by an equilibrium between the rates of immigration and extinction
scientific theory - Answers -an explanation that is generally broad in scope, is
supported by a large body of evidence, and that can serve as the basis for new
hypothesis and experimentation
A diploid organism has the genotype AaBbCc for three loci, each of which is located on
a different chromosome. A normal gamete produced by this organism could have which
of the following genotypes? - Answers -AbC
Which of the following amino acids can contribute to the 3-dimensional structure of a
protein by forming covalent bonds with an identical amino acid in another part of the
protein? - Answers -contains SH
The sciatic nerve from a frog was isolated and placed into a nerve chamber. A recording
of an action potential was measured when the nerve was bathed in a solution that
, mimics the extracellular fluid typically surrounding a cell, and the nerve was stimulated.
The recording is shown above. If the toxin TTX, a potent sodium-channel blocker, is
added to the bathing solution and the nerve is stimulated using a stimulus of the same
strength, what will be the most likely change in the action potential? - Answers -the
action potential will not occur, because depolarization will not occur
Sea star wasting syndrome is decimating some populations of sea stars along the North
American Pacific coast. Sea stars are the only natural predator of sea urchins and
mussels in some portions of the ecosystem. Which of the following is most likely a
concern for scientists studying the ecosystem? - Answers -w/o sea stars, the sea
urchin and mussel populations will increase and eliminated other species in the
ecosystem
Which of the following statements regarding the water cycle is correct? - Answers -the
water cycle differs from other biogeochemical cycles because most water moves
through ecosystems by physical rather than chemical processes
The skeletal structures of the human arm and whale flipper (pectoral fin) are shown
above. The arm and flipper are examples of... - Answers -homologous structures
the various structures in different species having the same function but have evolved
separately - Answers -analogous structures
Which of the following is required to initiate transcription of a particular gene in
eukaryotic cells? - Answers -an RNA polymerase associates with transcription factors
bound to the gene's regulatory sequences
In a plant, undifferentiated cells that can divide throughout the life of the plant to enable
growth are found in which of the following? - Answers -meristem
Investigators have immunized a rabbit with substance P. They are studying the effect of
the immunization on production of anti-substance P antibodies over a 2-week period
following the immunization. Which of the following is the best hypothesis for the
experiment? - Answers -antibody production by the rabbit in response to substance P
will increase over a 2-week period
The evaporation of water through the stomata in plant leaves, which creates a negative
pressure and causes water to be absorbed into the plant through the roots. - Answers -
Transpiration
Which of the following conditions would cause the most rapid lowering of the water level
in the pipet? - Answers -increasing the light intensity
Aphids are small insects that can rest on the stems and leaves of plants and insert their
needlelike mouthpiece directly into the phloem of the plants. Which of the following is
