Which of the following adaptations is common to all seed plants?
D) reduced gametophytes
E) All of the listed responses are correct.
All of the listed responses are correct.
Which one of the following is true of seed plants, but NOT true of seedless plants?
A) The spore is the main means of dispersing the offspring.
B) The gametophyte is reduced and dependent on the sporophyte.
C) A film of water is necessary for sperm to come in contact with eggs.
D) The sporophyte is dependent on the gametophyte.
E) The sporophyte is large, and the gametophyte is small and independent.
The gametophyte is reduced and dependent on the sporophyte.
The diploid generation of the plant life cycle always _____.
A) produces eggs and sperm
B) is called the gametophyte
C) produces spores
D) develops from a spore
E) is larger and more conspicuous than the haploid stage
The closest seedless relatives of seed plants produce one kind of spore that gives rise to a bisexual gametophyte. What does this suggest about the ancestors of seed plants?
A) They were homosporous.
B) They produced separate male and female gametophytes.
C) They were bryophytes.
D) They were gymnosperms.
E) They were heterosporous.
They were homosporous.
The eggs of seed plants are fertilized within ovules, and the ovules then develop into _____.
The cells within pollen grains are _____ and together comprise the _____.
A) diploid ... sperm nuclei
B) diploid ... spores
C) haploid ... spores
D) diploid ... a new sporophyte
E) haploid ... male gametophyte
haploid ... male gametophyte
Which example below is evidence provided by living gymnosperms of an evolutionary transition between seedless and seed plants?
A) The sperm of some gymnosperms have flagella.
B) The sperm of gymnosperms do not require water or mobility for fertilization.
C) Gymnosperms only have one integument.
D) In gymnosperms, two sperm are discharged into the pollen tube.
E) Some gymnosperms do not have reduced gametophytes.
The sperm of some gymnosperms have flagella.
Seeds have advantages over spores. Which of the following is the best statement of this?
A) Seeds contain embryonic plants, an abundant food supply, and a protective covering.
B) Seeds can survive even in conditions that are unfavorable for the parent plants.
C) Most seeds are poisonous; therefore, they are not consumed by animals and persist in the environment for long periods of time.
D) Seeds can survive for extended periods of time at reduced metabolic rates.
E) Seeds are single cells, demanding fewer nutrients from the parent plants.
Seeds contain embryonic plants, an abundant food supply, and a protective covering.
Which gymnosperm phylum below is characterized by large cones and fern-like leaves and thrived during the Mesozoic?
Dietary supplements and decongestants containing ephedrine have recently become more strongly regulated in the United States. Ephedrine is an extract of a plant belonging to which phylum?
A) phylum Ginkgophyta
B) phylum Gnetophyta
C) phylum Anthopyta
D) phylum Coniferophyta
E) phylum Cycadophyta
What significant change occurred on Earth between the Carboniferous period and the Permian period that most likely contributed to the success of the gymnosperms?
A) The breakup of Pangaea changed the flora and fauna of Earth dramatically.
B) Reptiles decreased in diversity and were replaced with amphibians better adapted for seed dispersal.
C) Insects developed flight.
D) An asteroid hit Earth, leading to mass extinctions that made way for gymnosperms to take over lands where other plants had perished.
E) The climate became drier and warmer.
The climate became drier and warmer.
What is located in the scalelike structures packed densely in pollen cones?
B) developing pollen tubes
C) developing seedlings
Each pollen grain of a gymnosperm contains a _____.
A) male gametophyte
D) fertilized ovule
In ovulate cones, megasporocytes undergo _____ and produce _____ megaspores.
A) mitosis ... diploid
B) meiosis ... haploid
C) mitosis ... haploid
D) meiosis ... diploid
E) Depending on environmental conditions, any of the listed responses may occur.
meiosis ... haploid
In a typical conifer, how long does it take for fertilization to occur after pollination?
A) It takes one season.
B) Pollination occurs after fertilization.
C) It takes one year.
D) The processes are simultaneous.
E) It takes three years.
It takes one year.
Which types of angiosperms would most likely be wind-pollinated rather than animal-pollinated?
A) maize and wheat
B) oak and maple trees
C) roses and tiger lilies
D) The first and second responses are correct.
E) None of the listed responses is correct. Plants with flowers are not wind-pollinated.
The first and second responses are correct.
Like gymnosperms, many grasses and angiosperm trees are wind-pollinated. To conserve energy, these angiosperms do not produce complete flowers (complete flowers have all four of the basic parts). Which part would be unnecessary for wind-pollinated angiosperms?
The portion of a flower that receives the pollen is the _____.
During pollination, pollen grains are transferred from the _____ to the _____.
A) anther ... stigma
B) carpel ... stigma
C) ovary ... anther
D) stigma ... ovary
E) anther ... sepal
anther ... stigma
A pea pod is formed from _____. A pea inside the pod is formed from _____.
A) an anther ... an ovule
B) an ovary ... a pollen grain
C) an ovary ... an ovule
D) endosperm ... an ovary
E) an ovule ... a carpel
an ovary ... an ovule
After fertilization, the _____ develops into a seed and the _____ develops into a fruit.
A) egg ... ovary
B) ovary ... ovule
C) pollen grain ... ovule
D) egg ... ovule
E) ovule ... ovary
ovule ... ovary
Which of the following best describes the function of fruits?
A) protection and dispersal of seeds
B) food storage for the plant to use over the winter
C) reward for pollinators
D) to distract herbivores from eating the leaves
E) Depending on the plant species, any of the listed responses are possible.
protection and dispersal of seeds
A plant is said to be cross-pollinated if _____.
A) it is pollinated by insects
B) pollen grains are transferred from a different flower on the same plant
C) its source of pollen is a different species of plant
D) it is pollinated by wind
E) pollen grains are transferred to a flower on a different plant
pollen grains are transferred to a flower on a different plant
The pollen tube releases two sperm cells into the embryo sac. The result of this is the _____.
A) fusion of both sperm nuclei with the egg nucleus and the formation of a triploid zygote
B) union of the two sperm nuclei, forming a zygote
C) formation of a gametophyte
D) union of one sperm nucleus with the egg nucleus and of the other sperm nucleus with two nuclei of the central cell, forming a triploid nucleus called the endosperm
E) union of one sperm nucleus with the egg nucleus and the disintegration of the other sperm nucleus
union of one sperm nucleus with the egg nucleus and of the other sperm nucleus with two nuclei of the central cell, forming a triploid nucleus called the endosperm
Of the following, which is a difference in how reproduction occurs in gymnosperms compared to angiosperms?
A) Only the sperm of angiosperms combine with two central cell nuclei to form triploid endosperm.
B) Double fertilization only occurs in gymnosperms.
C) Only gymnosperms can contain male and female sporangia on the same plant.
D) Only angiosperms have reduced gametophytes.
E) Only angiosperm pollen grains form pollen tubes.
Only the sperm of angiosperms combine with two central cell nuclei to form triploid endosperm.
The triploid nucleus of the embryo sac develops into the _____.
In gymnosperms, the seed coat develops from the integument. In angiosperms, the seed coat develops from the _____.
B) ovary wall
C) female gametophyte
The vast majority of angiosperms with two cotyledons formerly classified as _____ are now classified as _____.
A) eudicots ... dicots
B) monocots ... magnoliids
C) eudicots ... basal angiosperms
D) dicots ... eudicots
E) monocots ... dicots
dicots ... eudicots
Which of the following characterizes eudicots?
A) scattered vascular bundles, netlike veins, floral parts in multiples of five
B) pollen grains with three openings, floral parts in multiples of three, netlike veins
C) leaves with parallel veins, taproot usually present, vascular bundles arranged in rings
D) one cotyledon, vascular bundles in rings, pollen grains with three openings
E) two cotyledons, netlike veins, taproot usually present
two cotyledons, netlike veins, taproot usually present
A bright pink flower with deep floral tubes will most likely be pollinated by which mechanism?
C) birds with long beaks
birds with long beaks
Six major crops-wheat, rice, maize, potatoes, cassava, and sweet potatoes-constitute what percentage of all the calories consumed by humans?
At current rates of deforestation, tropical rain forests will be eliminated in _____ years.
Besides the plant tissue that humans ingest, which angiosperm tissue is most directly important for human survival?