BIO 1500 EXAM #3 QUESTIONS AND
ANSWERS
Angiosperms use which temporary reproductive structures that are not present in
any other
group of plants?
A) cones
B) carpels
C) receptacles
D) flowers
E) seeds - ANSWER-flowers
The developmental transition during which plants become able to respond to
external and/or
internal signals that promote flowering is known as
A) cloning.
B) initiation.
C) abscission.
D) perennial development.
E) phase change. - ANSWER-phase change
One way to improve crop productivity is to modify flowering time. This can allow for
multiple growing seasons in one year, and can also increase grain production
because a smaller
plant has lower resource needs. You are approached by an agricultural company
that wants to
create an early-flowering transgenic plant. Using your knowledge of Arabidopsis
genetics, which
genetic modifications would you suggest?
A) Inhibition of the embryonic flower (EMF) gene or overexpression of the LEAFY
(LFY) gene would work.
B) Inhibition of the LEAFY (LFY) gene or overexpression of the embryonic flower
(emf) gene
would work.
C) Inhibition of either the embryonic flower (emf) gene or the LEAFY (LFY) gene
would work.
D) Early flowering is not possible in Arabidopsis, and is not likely to be possible in
other plants. - ANSWER-Inhibition of the embryonic flower (EMF) gene or
overexpression of the LEAFY (LFY) gene would work.
Arabidopsis plants with a mutation in the gene embryonic Flower (EMF) produce
flowers
almost immediately after germination, before shoot growth occurs. What is the
normal role of
this gene?
A) The wildtype EMF allele causes growth of flowers in the embryo.
B) The wildtype EMF allele causes death of the shoot tissue.
C) The wildtype EMF allele prevents flowering from happening too soon.
,D) The wildtype EMF allele prevents phase change and facilitates flower
determination. - ANSWER-the wildtype EMF allele prevents flowering from
happening too soon.
Interrupting the night with a flash of light can trigger flowering in a long-day plant.
Why
doesn't introducing a short period of darkness during the day cause a short-day plant
to flower?
A) Sunlight contains enough far-red light to inhibit phytochrome induction of
flowering.
B) A brief dark period is not sufficient to trigger flowering.
C) Phytochrome is only active in the dark.
D) The circadian clock is less responsive during the day than at night.
E) The phytochrome response also requires cool nighttime temperatures. -
ANSWER-a brief dark period is not sufficient to trigger flowering
Which of the following statements about flowering plants is TRUE?
A) A short-day plant requires nights longer than a certain critical period to trigger
flowering.
B) A long-day plant requires nights shorter than a certain critical period to inhibit
flowering.
C) A short-day plant requires daylight of short wavelengths.
D) A long-day plant requires long wavelengths during the night.
E) A long-day plant requires long days alternating with short days. - ANSWER-a
short-day plant requires nights longer than a certain critical period to trigger flowering
Why do many plants use the photoperiodic pathway to regulate the timing of flower
formation?
A) Flower petals carry out high levels of photosynthesis and require high light
conditions.
B) A minimum amount of light is always necessary for flowering.
C) This allows plants to link flowering to temperature, which corresponds to the
season when
conditions are optimal.
D) This allows plants to link flowering to day length, which corresponds to the season
when conditions are optimal. - ANSWER-this allows plants to link flowering to day
length, which corresponds to the season when conditions are optimal
You buy a Schlumbergera plant, also known as a Christmas Cactus, to decorate the
desk
where you study late into the night. It is now December, and there are no signs of
flower buds
forming. What is the most plausible explanation for the lack of flowers?
A) Flowering in this plant is controlled by both day length and temperature. The
warm room and
extended exposure to light are preventing flower formation.
B) The room is too cold for a cactus plant, which requires hot, desert conditions to
flower.
C) Cacti are gymnosperms, not angiosperms, and thus do not form flowers.
, D) As a long-day plant, the cactus requires a high light to dark ratio to flower, so it
must be exposed to more sunlight. - ANSWER-as a long-day plant, the cactus
requires a high light to dark ratio to flower, so it must be exposed to more sunlight
Competence means that a plant is ________, while determination means that a plant
tissue
________. The acquisition of flowering competence is an example of a ________.
A) capable of responding to signals that trigger a fate change; remains capable of
adopting more
than one possible developmental fate; phaseolus
B) unresponsive to signals that trigger a fate change; is committed to a specific
developmental
fate; fate change
C) in the process of responding to signals that trigger a fate change; was driven to
adopt an
abnormal developmental fate by transgene expression; flowerization
D) capable of responding to signals that trigger a fate change; is committed to a
specific
developmental fate; phase change - ANSWER-capable of responding to signals that
trigger a fate change; is committed to a specific developmental fate; phase change
Solid worms that lack a body cavity are known as
A) acoelomates.
B) pseudocoelomates.
C) triploblastic.
D) coelomates.
E) diploblastic. - ANSWER-acoelomates
Which of the following terms is mismatched with its meaning or characteristics?
A) Diploblastic—ectoderm and mesoderm
B) Triploblastic—ectoderm, mesoderm, and endoderm
C) Parazoa—lacks symmetry; no tissues
D) Eumetazoa—definite symmetry; tissues organized
E) Chordate—animal with notochord - ANSWER-diploblastic- ectoderm and
mesoderm
Segmentation is the subdivision of the body into segments or metameres. True
segmentation is found in which of the following phyla?
A) Annelida, Mollusca, Arthropoda
B) Echinodermata, Platyhelminthes, Cnidaria
C) Mollusca, Chordata, Annelida
D) Arthropoda, Chordata, Porifera
E) Arthropoda, Annelida, Chordata - ANSWER-arthropoda, annelida, chordata
Molecular data confirm that cnidarians branched off from the rest of animals before
________ evolved.
A) echinoderms
B) Porifera
C) mollusks
D) bilateral symmetry
ANSWERS
Angiosperms use which temporary reproductive structures that are not present in
any other
group of plants?
A) cones
B) carpels
C) receptacles
D) flowers
E) seeds - ANSWER-flowers
The developmental transition during which plants become able to respond to
external and/or
internal signals that promote flowering is known as
A) cloning.
B) initiation.
C) abscission.
D) perennial development.
E) phase change. - ANSWER-phase change
One way to improve crop productivity is to modify flowering time. This can allow for
multiple growing seasons in one year, and can also increase grain production
because a smaller
plant has lower resource needs. You are approached by an agricultural company
that wants to
create an early-flowering transgenic plant. Using your knowledge of Arabidopsis
genetics, which
genetic modifications would you suggest?
A) Inhibition of the embryonic flower (EMF) gene or overexpression of the LEAFY
(LFY) gene would work.
B) Inhibition of the LEAFY (LFY) gene or overexpression of the embryonic flower
(emf) gene
would work.
C) Inhibition of either the embryonic flower (emf) gene or the LEAFY (LFY) gene
would work.
D) Early flowering is not possible in Arabidopsis, and is not likely to be possible in
other plants. - ANSWER-Inhibition of the embryonic flower (EMF) gene or
overexpression of the LEAFY (LFY) gene would work.
Arabidopsis plants with a mutation in the gene embryonic Flower (EMF) produce
flowers
almost immediately after germination, before shoot growth occurs. What is the
normal role of
this gene?
A) The wildtype EMF allele causes growth of flowers in the embryo.
B) The wildtype EMF allele causes death of the shoot tissue.
C) The wildtype EMF allele prevents flowering from happening too soon.
,D) The wildtype EMF allele prevents phase change and facilitates flower
determination. - ANSWER-the wildtype EMF allele prevents flowering from
happening too soon.
Interrupting the night with a flash of light can trigger flowering in a long-day plant.
Why
doesn't introducing a short period of darkness during the day cause a short-day plant
to flower?
A) Sunlight contains enough far-red light to inhibit phytochrome induction of
flowering.
B) A brief dark period is not sufficient to trigger flowering.
C) Phytochrome is only active in the dark.
D) The circadian clock is less responsive during the day than at night.
E) The phytochrome response also requires cool nighttime temperatures. -
ANSWER-a brief dark period is not sufficient to trigger flowering
Which of the following statements about flowering plants is TRUE?
A) A short-day plant requires nights longer than a certain critical period to trigger
flowering.
B) A long-day plant requires nights shorter than a certain critical period to inhibit
flowering.
C) A short-day plant requires daylight of short wavelengths.
D) A long-day plant requires long wavelengths during the night.
E) A long-day plant requires long days alternating with short days. - ANSWER-a
short-day plant requires nights longer than a certain critical period to trigger flowering
Why do many plants use the photoperiodic pathway to regulate the timing of flower
formation?
A) Flower petals carry out high levels of photosynthesis and require high light
conditions.
B) A minimum amount of light is always necessary for flowering.
C) This allows plants to link flowering to temperature, which corresponds to the
season when
conditions are optimal.
D) This allows plants to link flowering to day length, which corresponds to the season
when conditions are optimal. - ANSWER-this allows plants to link flowering to day
length, which corresponds to the season when conditions are optimal
You buy a Schlumbergera plant, also known as a Christmas Cactus, to decorate the
desk
where you study late into the night. It is now December, and there are no signs of
flower buds
forming. What is the most plausible explanation for the lack of flowers?
A) Flowering in this plant is controlled by both day length and temperature. The
warm room and
extended exposure to light are preventing flower formation.
B) The room is too cold for a cactus plant, which requires hot, desert conditions to
flower.
C) Cacti are gymnosperms, not angiosperms, and thus do not form flowers.
, D) As a long-day plant, the cactus requires a high light to dark ratio to flower, so it
must be exposed to more sunlight. - ANSWER-as a long-day plant, the cactus
requires a high light to dark ratio to flower, so it must be exposed to more sunlight
Competence means that a plant is ________, while determination means that a plant
tissue
________. The acquisition of flowering competence is an example of a ________.
A) capable of responding to signals that trigger a fate change; remains capable of
adopting more
than one possible developmental fate; phaseolus
B) unresponsive to signals that trigger a fate change; is committed to a specific
developmental
fate; fate change
C) in the process of responding to signals that trigger a fate change; was driven to
adopt an
abnormal developmental fate by transgene expression; flowerization
D) capable of responding to signals that trigger a fate change; is committed to a
specific
developmental fate; phase change - ANSWER-capable of responding to signals that
trigger a fate change; is committed to a specific developmental fate; phase change
Solid worms that lack a body cavity are known as
A) acoelomates.
B) pseudocoelomates.
C) triploblastic.
D) coelomates.
E) diploblastic. - ANSWER-acoelomates
Which of the following terms is mismatched with its meaning or characteristics?
A) Diploblastic—ectoderm and mesoderm
B) Triploblastic—ectoderm, mesoderm, and endoderm
C) Parazoa—lacks symmetry; no tissues
D) Eumetazoa—definite symmetry; tissues organized
E) Chordate—animal with notochord - ANSWER-diploblastic- ectoderm and
mesoderm
Segmentation is the subdivision of the body into segments or metameres. True
segmentation is found in which of the following phyla?
A) Annelida, Mollusca, Arthropoda
B) Echinodermata, Platyhelminthes, Cnidaria
C) Mollusca, Chordata, Annelida
D) Arthropoda, Chordata, Porifera
E) Arthropoda, Annelida, Chordata - ANSWER-arthropoda, annelida, chordata
Molecular data confirm that cnidarians branched off from the rest of animals before
________ evolved.
A) echinoderms
B) Porifera
C) mollusks
D) bilateral symmetry
