Flowering_plant

qas: question: What are the most diverse group of land plants?
answers: text: angiosperms
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question: How many species of flowering plants are there about?
answers: text: 350,000
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question: What do angiosperms have in common with gymnosperms?
answers: text: seed-producing plants
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question: What does an angiosperm produce its seeds within?
answers: text: an enclosure
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question: What is the Greek word for "case" or "casing"?
answers: text: angeion
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question: Where does the term gymnosperm originate?
is_impossible: yes

question: What are gymnosperms known as?
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question: What do angeion have in common with angiosperms?
is_impossible: yes

question: How is production of fruits distinguished from a fruiting plant?
is_impossible: yes

question: What does gymnosperm mean etymologically?
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context: The flowering plants (angiosperms), also known as Angiospermae or Magnoliophyta, are the most diverse group of land plants, with about 350,000 species. Like gymnosperms, angiosperms are seed-producing plants; they are distinguished from gymnosperms by characteristics including flowers, endosperm within the seeds, and the production of fruits that contain the seeds. Etymologically, angiosperm means a plant that produces seeds within an enclosure, in other words, a fruiting plant. The term "angiosperm" comes from the Greek composite word (angeion-, "case" or "casing", and sperma, "seed") meaning "enclosed seeds", after the enclosed condition of the seeds.

qas: question: How long have higher plants lived on land?
answers: text: at least 475 million years
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question: How did early plants reproduce sexually?
answers: text: with flagellated, swimming sperm
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question: Upright meisporangia allowed what to be dispersed to new habitats?
answers: text: spores
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question: What are the nearest algal relatives existing today?
answers: text: Charophycean green algae
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question: What is the common name for Selaginella?
answers: text: the spike-moss
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question: What do the first green algae not produce?
is_impossible: yes

question: What does the pollen of spike-moss produce for reproduction?
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question: What does the pollen of spike-moss do to reach the female?
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question: What suggests that confiers have lived on land for 475 million years?
is_impossible: yes

question: What did Charophycean green algae develop to disperse by spores into new habitats?
is_impossible: yes
context: Fossilized spores suggest that higher plants (embryophytes) have lived on land for at least 475 million years. Early land plants reproduced sexually with flagellated, swimming sperm, like the green algae from which they evolved. An adaptation to terrestrialization was the development of upright meiosporangia for dispersal by spores to new habitats. This feature is lacking in the descendants of their nearest algal relatives, the Charophycean green algae. A later terrestrial adaptation took place with retention of the delicate, avascular sexual stage, the gametophyte, within the tissues of the vascular sporophyte. This occurred by spore germination within sporangia rather than spore release, as in non-seed plants. A current example of how this might have happened can be seen in the precocious spore germination in Selaginella, the spike-moss. The result for the ancestors of angiosperms was enclosing them in a case, the seed. The first seed bearing plants, like the ginkgo, and conifers (such as pines and firs), did not produce flowers. The pollen grains (males) of Ginkgo and cycads produce a pair of flagellated, mobile sperm cells that "swim" down the developing pollen tube to the female and her eggs.

qas: question: What did Charles Darwin call the sudden appearance of nearly modern flowers in the fossil record?
answers: text: abominable mystery
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question: What type of fossil is the recently discovered Archaefructus?
answers: text: angiosperm
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question: What fossil evidence is lacking when it comes to flowers?
answers: text: evidence showing exactly how flowers evolved
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question: From what period does fossilized pollen suggest an older date for angiosperm origin?
answers: text: Middle Triassic
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question: What relationship proposed on the basis of morphological evidence has recently been disputed?
answers: text: relationship between angiosperms and gnetophytes
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question: What was ancestors of angiosperms suddenly appearing called by Charles Darwin?
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question: What have several groups of Archaefructus been proposed to be?
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question: What is missing to show how ancestors of angiosperms diverged from an unknown group?
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question: Why has the relationship between gnetophytes and gymnosperms been disputed?
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question: What type of fossil is the recently discovered Sanmiguelia?
is_impossible: yes
context: The apparently sudden appearance of nearly modern flowers in the fossil record initially posed such a problem for the theory of evolution that it was called an "abominable mystery" by Charles Darwin. However, the fossil record has considerably grown since the time of Darwin, and recently discovered angiosperm fossils such as Archaefructus, along with further discoveries of fossil gymnosperms, suggest how angiosperm characteristics may have been acquired in a series of steps. Several groups of extinct gymnosperms, in particular seed ferns, have been proposed as the ancestors of flowering plants, but there is no continuous fossil evidence showing exactly how flowers evolved. Some older fossils, such as the upper Triassic Sanmiguelia, have been suggested. Based on current evidence, some propose that the ancestors of the angiosperms diverged from an unknown group of gymnosperms in the Triassic period (245–202 million years ago). Fossil angiosperm-like pollen from the Middle Triassic (247.2–242.0 Ma) suggests an older date for their origin. A close relationship between angiosperms and gnetophytes, proposed on the basis of morphological evidence, has more recently been disputed on the basis of molecular evidence that suggest gnetophytes are instead more closely related to other gymnosperms.[citation needed]

qas: question: How many distinct rounds of genome duplication events are suspected in the evolution of seed plants?
answers: text: two
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question: When did the first whole genome duplication event occur?
answers: text: 319 million years ago
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question: What type of event perhaps created the line which led to modern flowering plants?
answers: text: whole genome duplication
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question: How are duplication events studied?
answers: text: by sequencing the genome of an ancient flowering plant
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question: Who coined the term "abominable mystery"?
answers: text: Darwin
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question: What appears to be the cause of duplicaton of seed plants?
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question: When did Darwin's "abominable mystery first appear?
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question: When was the ancient plant used in the study dated to?
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question: How are modern plants studied?
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question: Who coined the term duplication event?
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context: The evolution of seed plants and later angiosperms appears to be the result of two distinct rounds of whole genome duplication events. These occurred at 319 million years ago and 192 million years ago. Another possible whole genome duplication event at 160 million years ago perhaps created the ancestral line that led to all modern flowering plants. That event was studied by sequencing the genome of an ancient flowering plant, Amborella trichopoda, and directly addresses Darwin's "abominable mystery."

qas: question: When is the earliest known macrofossil identified as an angiosperm dated?
answers: text: about 125 million years BP
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question: What is the earliest known angiosperm?
answers: text: Archaefructus liaoningensis
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question: What pushes the age of angiosperm 5 million years further back?
answers: text: pollen
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question: How long ago has circumstantial evidence has been found for the existence of angiosperms?
answers: text: 250 million years ago
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question: What group of now extinct seed plants had many of the traits of what are now flowering plants?
answers: text: Gigantopterids
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question: What is Oleanne, the earliest macrofossil, traditionally considered to be?
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question: What evidence has shown that flowering plants existed 125 million years BP?
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question: What has been found in ginko deposits of that age with gigantopterid fossils?
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question: What do Oleanne share morphological traits with?
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question: What are not known to have Permian deposits themselves?
is_impossible: yes
context: The earliest known macrofossil confidently identified as an angiosperm, Archaefructus liaoningensis, is dated to about 125 million years BP (the Cretaceous period), whereas pollen considered to be of angiosperm origin takes the fossil record back to about 130 million years BP. However, one study has suggested that the early-middle Jurassic plant Schmeissneria, traditionally considered a type of ginkgo, may be the earliest known angiosperm, or at least a close relative. In addition, circumstantial chemical evidence has been found for the existence of angiosperms as early as 250 million years ago. Oleanane, a secondary metabolite produced by many flowering plants, has been found in Permian deposits of that age together with fossils of gigantopterids. Gigantopterids are a group of extinct seed plants that share many morphological traits with flowering plants, although they are not known to have been flowering plants themselves.

qas: question: When does a great diversity of angiosperms appear in the fossil record?
answers: text: approximately 100 million years ago
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question: What is the appearance of a large amount of angiosperms in the fossil record known as?
answers: text: great angiosperm radiation,
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question: When did the division of the eight main groups of angiosperms occur?
answers: text: 40 million years ago
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question: What were the angiosperms up to by the late Cretaceous?
answers: text: dominated environments
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question: Beech and maple had already appeared by what period?
answers: text: Cretaceous
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question: When does a diversity of magnoliids appear in the fossil record?
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question: What is the appearance of ferns in the fossil record called?
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question: By the end of the Tertiary, what did angiosperms dominate?
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question: When did eudicots replace conifers as dominant trees?
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question: When had eight main groups of Chloranthaceae recognizable as belonging to modern families appear?
is_impossible: yes
context: The great angiosperm radiation, when a great diversity of angiosperms appears in the fossil record, occurred in the mid-Cretaceous (approximately 100 million years ago). However, a study in 2007 estimated that the division of the five most recent (the genus Ceratophyllum, the family Chloranthaceae, the eudicots, the magnoliids, and the monocots) of the eight main groups occurred around 140 million years ago. By the late Cretaceous, angiosperms appear to have dominated environments formerly occupied by ferns and cycadophytes, but large canopy-forming trees replaced conifers as the dominant trees only close to the end of the Cretaceous 66 million years ago or even later, at the beginning of the Tertiary. The radiation of herbaceous angiosperms occurred much later. Yet, many fossil plants recognizable as belonging to modern families (including beech, oak, maple, and magnolia) had already appeared by the late Cretaceous.

qas: question: What is one proposed explanation for the instant appearance of flowering plants?
answers: text: Island genetics
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question: What is island genetics thought to be a default source of?
answers: text: speciation
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question: What did radical adaptations seem to have required?
answers: text: inferior transitional forms
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question: How did an isolated setting like an island help flowering plants evolve?
answers: text: highly specialized relationship with some specific animal
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question: What are bees descended from?
answers: text: wasps
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question: What are transitional forms descended from?
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question: What is an explanation for the sudden appearance of fig wasps?
is_impossible: yes

question: What does a relationship between bees and wasps result in?
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question: What is carrying pollen thought to be a common source of?
is_impossible: yes

question: How did flowering plants help transitional forms evolve?
is_impossible: yes
context: Island genetics provides one proposed explanation for the sudden, fully developed appearance of flowering plants. Island genetics is believed to be a common source of speciation in general, especially when it comes to radical adaptations that seem to have required inferior transitional forms. Flowering plants may have evolved in an isolated setting like an island or island chain, where the plants bearing them were able to develop a highly specialized relationship with some specific animal (a wasp, for example). Such a relationship, with a hypothetical wasp carrying pollen from one plant to another much the way fig wasps do today, could result in the development of a high degree of specialization in both the plant(s) and their partners. Note that the wasp example is not incidental; bees, which, it is postulated, evolved specifically due to mutualistic plant relationships, are descended from wasps.

qas: question: What are animals also a part of?
answers: text: distribution of seeds
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question: What did the enlargement of flower parts evolve to form?
answers: text: Fruit
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question: What does a plant get out of forming fruit?
answers: text: seed-dispersal
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question: What are many mutualistic relationships, thus failing to survive competition? 
answers: text: fragile
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question: What turned out to be unusually effective for plants to reproduce?
answers: text: flowering
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question: What did competition prove to be effective at doing?
is_impossible: yes

question: What did mutualistic relationships spread to eventually become?
is_impossible: yes

question: How does a plant benefit from competition?
is_impossible: yes

question: What reproductive method spread widely but made plants fragile?
is_impossible: yes

question: What did accidentally scattering seeds help flower parts evolve to form?
is_impossible: yes
context: Animals are also involved in the distribution of seeds. Fruit, which is formed by the enlargement of flower parts, is frequently a seed-dispersal tool that attracts animals to eat or otherwise disturb it, incidentally scattering the seeds it contains (see frugivory). Although many such mutualistic relationships remain too fragile to survive competition and to spread widely, flowering proved to be an unusually effective means of reproduction, spreading (whatever its origin) to become the dominant form of land plant life.

qas: question: What uses a combination of genes to form new shoots?
answers: text: Flower ontogeny
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question: What were plant parts like in their primitive days?
answers: text: separate from (but in contact with) each other
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question: How did flowers become bixsexual?
answers: text: grow in a spiral pattern
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question: What did some plant parts do as they evolved?
answers: text: fused together
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question: What is a term for a plant with a specific sex per flower?
answers: text: "ovary-inferior"
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question: What was dominated by the male parts?
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question: How did flowers tend to grow when they were male dominant?
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question: What did some plant parts do when the flower had only male parts?
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question: During flower ontogeny, what was a plant of a specific sex called?
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question: What do ovary inferior plants use to form new shoots?
is_impossible: yes
context: Flower ontogeny uses a combination of genes normally responsible for forming new shoots. The most primitive flowers probably had a variable number of flower parts, often separate from (but in contact with) each other. The flowers tended to grow in a spiral pattern, to be bisexual (in plants, this means both male and female parts on the same flower), and to be dominated by the ovary (female part). As flowers evolved, some variations developed parts fused together, with a much more specific number and design, and with either specific sexes per flower or plant or at least "ovary-inferior".

qas: question: How long has flower evolution occurred? 
answers: text: present day
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question: Humans have effected some flowers so much they can no longer do what in nature?
answers: text: pollinated
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question: What heritage do many modern domesticated flower species have?
answers: text: formerly simple weeds
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question: Why did weeds grow with human crops?
answers: text: symbiotic companion plant relationships
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question: What feature helped flowers not get plucked?
answers: text: prettiest
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question: What has happened to weeds due to human influence?
is_impossible: yes

question: How long has weed evolution occurred?
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question: What was the origin of many simple weeds?
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question: What have weeds developed a dependence on?
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question: What characteristic caused crops not to be harvested?
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context: Flower evolution continues to the present day; modern flowers have been so profoundly influenced by humans that some of them cannot be pollinated in nature. Many modern domesticated flower species were formerly simple weeds, which sprouted only when the ground was disturbed. Some of them tended to grow with human crops, perhaps already having symbiotic companion plant relationships with them, and the prettiest did not get plucked because of their beauty, developing a dependence upon and special adaptation to human affection.

qas: question: What three groups were the first to diverge from angiosperm?
answers: text: Amborellales, Nymphaeales, and Austrobaileyales
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question: What term refers to the first three groups to diverge from angiosperm?
answers: text: basal
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question: How clear is the relationship between the broadest of the three non-basal angiosperm groups?
answers: text: unclear
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question: What group do some analyses seem to indicate diverged first?
answers: text: magnoliids
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question: What were the first three groups to diverge from magnoliids?
is_impossible: yes

question: What do Amborellales tend to group with instead of monocots?
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question: What is the status of the relationship between Nymphaeales and monocots?
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question: What attitude is there about the first magnoliids diverging from the ancestral angiosperm?
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question: What do some eudicots indicate diverged first?
is_impossible: yes
context: The exact relationship between these eight groups is not yet clear, although there is agreement that the first three groups to diverge from the ancestral angiosperm were Amborellales, Nymphaeales, and Austrobaileyales. The term basal angiosperms refers to these three groups. Among the rest, the relationship between the three broadest of these groups (magnoliids, monocots, and eudicots) remains unclear. Some analyses make the magnoliids the first to diverge, others the monocots. Ceratophyllum seems to group with the eudicots rather than with the monocots.

qas: question: What term did Paul Hermann come up with in 1690?
answers: text: Angiosperm
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question: What did Hermann use the term angiosperm a primary division of in the plant kingdom?
answers: text: primary
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question: Who restricted the application of the angiosperm term?
answers: text: Carl Linnaeus
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question: What did Robert Brown establish the existence of in Cycadeae and Coniferae?
answers: text: naked ovules
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question: What is the group-name angiosperm has been used for by botanical writers?
answers: text: other dicotyledonous plants
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question: Who coined the term dicotyledonous?
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question: In what year was the term dicotyledonous created?
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question: Why did Robert Brown use the term dicotyledonous?
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question: How was the term angeion maintained by Robert Brown?
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question: In 1690 what happened to the term angeion as used by Robert Brown?
is_impossible: yes
context: The botanical term "Angiosperm", from the Ancient Greek αγγείον, angeíon (bottle, vessel) and σπέρμα, (seed), was coined in the form Angiospermae by Paul Hermann in 1690, as the name of one of his primary divisions of the plant kingdom. This included flowering plants possessing seeds enclosed in capsules, distinguished from his Gymnospermae, or flowering plants with achenial or schizo-carpic fruits, the whole fruit or each of its pieces being here regarded as a seed and naked. The term and its antonym were maintained by Carl Linnaeus with the same sense, but with restricted application, in the names of the orders of his class Didynamia. Its use with any approach to its modern scope became possible only after 1827, when Robert Brown established the existence of truly naked ovules in the Cycadeae and Coniferae, and applied to them the name Gymnosperms.[citation needed] From that time onward, as long as these Gymnosperms were, as was usual, reckoned as dicotyledonous flowering plants, the term Angiosperm was used antithetically by botanical writers, with varying scope, as a group-name for other dicotyledonous plants.

qas: question: In taxonomies, what type of group are flowering plants treated?
answers: text: coherent
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question: What does anthophyta mean?
answers: text: flowering plants
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question: What do the Wettstein and Engler systems use at the assigned rank of subdivision?
answers: text: Angiospermae
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question: How does the APG system of 1998, with its 2003 and 2009 revisions, treat flowering plants?
answers: text: a clade called angiosperms
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question: What formal subclass classification were flowering plants given in 2009?
answers: text: Magnoliidae
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question: What are coherent groups not linked to?
is_impossible: yes

question: What do Anthophyta and Magnoliophytina use as the assigned rank of subdivision?
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question: How does the APG system of 1996 treat flowering plants?
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question: What taxonomy was published alongside the 2003 revision?
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question: What does Magnoliophytina mean?
is_impossible: yes
context: In most taxonomies, the flowering plants are treated as a coherent group. The most popular descriptive name has been Angiospermae (Angiosperms), with Anthophyta ("flowering plants") a second choice. These names are not linked to any rank. The Wettstein system and the Engler system use the name Angiospermae, at the assigned rank of subdivision. The Reveal system treated flowering plants as subdivision Magnoliophytina (Frohne & U. Jensen ex Reveal, Phytologia 79: 70 1996), but later split it to Magnoliopsida, Liliopsida, and Rosopsida. The Takhtajan system and Cronquist system treat this group at the rank of division, leading to the name Magnoliophyta (from the family name Magnoliaceae). The Dahlgren system and Thorne system (1992) treat this group at the rank of class, leading to the name Magnoliopsida. The APG system of 1998, and the later 2003 and 2009 revisions, treat the flowering plants as a clade called angiosperms without a formal botanical name. However, a formal classification was published alongside the 2009 revision in which the flowering plants form the Subclass Magnoliidae.

qas: question: What internal component has undergone considerable revision?
answers: text: classification
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question: What system did Arthur Cronquist put forth in 1968, but not publish in full form until 1981?
answers: text: The Cronquist system
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question: What consensus is the AGP trying to reach?
answers: text: how the flowering plants should be arranged
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question: Who published an influential reclassification of the angiosperms in 1998?
answers: text: APG
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question: What classification system was published by APG II in 1968?
is_impossible: yes

question: When was the APG II system published fully?
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question: What is no longer believed about the APG system?
is_impossible: yes

question: What consensus has emerged through the work of Arthur Cronquist?
is_impossible: yes

question: What did Arthur Cronquist publish about angiosperms in 1998?
is_impossible: yes
context: The internal classification of this group has undergone considerable revision. The Cronquist system, proposed by Arthur Cronquist in 1968 and published in its full form in 1981, is still widely used but is no longer believed to accurately reflect phylogeny. A consensus about how the flowering plants should be arranged has recently begun to emerge through the work of the Angiosperm Phylogeny Group (APG), which published an influential reclassification of the angiosperms in 1998. Updates incorporating more recent research were published as APG II in 2003 and as APG III in 2009.

qas: question: What type of groups do monocots form, based on a recent APG studies?
answers: text: monophyletic
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question: Eudicots or tricolpates are part of a monophyletic group formed by what species?
answers: text: dicot
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question: What third major clade can many dicot species be found in?
answers: text: magnoliids
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question: How many species dicot species are magnoliids?
answers: text: about 9,000
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question: Basal angiosperms are what type of grouping of primitive species?
answers: text: paraphyletic
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question: How many species of Chloranthaceae are eudicots?
is_impossible: yes

question: What do studies by the monophyletic group show?
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question: What do a majority of monocot Ceratophyllaceae species form?
is_impossible: yes

question: What do the remaining monocot species belong to?
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question: What is the group known as that remainig monocot species belong to?
is_impossible: yes
context: Recent studies, as by the APG, show that the monocots form a monophyletic group (clade) but that the dicots do not (they are paraphyletic). Nevertheless, the majority of dicot species do form a monophyletic group, called the eudicots or tricolpates. Of the remaining dicot species, most belong to a third major clade known as the magnoliids, containing about 9,000 species. The rest include a paraphyletic grouping of primitive species known collectively as the basal angiosperms, plus the families Ceratophyllaceae and Chloranthaceae.

qas: question: What is the estimated range for the number of flowering plants?
answers: text: 250,000 to 400,000
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question: How many species of moss is there?
answers: text: 12,000
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question: What does the large number of flowering plant species indicate is true of them in general?
answers: text: diverse
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question: What are the minimum number of families in the APG system?
answers: text: 402
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question: How many families are in AGP III?
answers: text: 415
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question: How is moss seen more than families in the system?
is_impossible: yes

question: What is true about families more than moss or pteridophytes?
is_impossible: yes

question: How many flowering plants are in APG in 1998?
is_impossible: yes

question: What are the minimum number of species of moss in the APG system?
is_impossible: yes

question: In APG III how many species of flowering plants are there?
is_impossible: yes
context: The number of species of flowering plants is estimated to be in the range of 250,000 to 400,000. This compares to around 12,000 species of moss or 11,000 species of pteridophytes, showing that the flowering plants are much more diverse. The number of families in APG (1998) was 462. In APG II (2003) it is not settled; at maximum it is 457, but within this number there are 55 optional segregates, so that the minimum number of families in this system is 402. In APG III (2009) there are 415 families.

qas: question: What shape are the bundles in the young stem of dicotyledons arranged in?
answers: text: an open ring
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question: What does the cambium separate?
answers: text: xylem and phloem
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question: What is a layer of meristem or formative tissue known as?
answers: text: cambium
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question: What results from the development of xylem on the inside and phloem on the outside?
answers: text: increase in thickness
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question: What's another name for the concentric rings in trees?
answers: text: annual rings
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question: What is formed  when a layer of dicotyledons is formed between the bundles?
is_impossible: yes

question: What causes a regular increase in young stems?
is_impossible: yes

question: What happens when the annual rings are crushed?
is_impossible: yes

question: How is soft phloem marked for each growth season?
is_impossible: yes

question: How are bundles in young stems arranged in branches?
is_impossible: yes
context: In the dicotyledons, the bundles in the very young stem are arranged in an open ring, separating a central pith from an outer cortex. In each bundle, separating the xylem and phloem, is a layer of meristem or active formative tissue known as cambium. By the formation of a layer of cambium between the bundles (interfascicular cambium), a complete ring is formed, and a regular periodical increase in thickness results from the development of xylem on the inside and phloem on the outside. The soft phloem becomes crushed, but the hard wood persists and forms the bulk of the stem and branches of the woody perennial. Owing to differences in the character of the elements produced at the beginning and end of the season, the wood is marked out in transverse section into concentric rings, one for each season of growth, called annual rings.

qas: question: What is the defining feature of angiosperms?
answers: text: flower
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question: What characteristic flowers show variation in?
answers: text: form and elaboration
is_impossible: no

question: What do flowers provide the best external feature for doing?
answers: text: establishing relationships among angiosperm species
is_impossible: no

question: What is it the function of the flower to ensure fertilization of?
answers: text: the ovule
is_impossible: no

question: What is the name of a branch system?
answers: text: inflorescence
is_impossible: no

question: What is a main feature of vegatative portion of a plant?
is_impossible: yes

question: What does the foliage-bearing part of the plant form to bear flowers?
is_impossible: yes

question: What are some things that an elaborate branch system shows?
is_impossible: yes

question: What does fruit with seeds provide to establish relationships among species?
is_impossible: yes

question: What is the function of the petiole?
is_impossible: yes
context: The characteristic feature of angiosperms is the flower. Flowers show remarkable variation in form and elaboration, and provide the most trustworthy external characteristics for establishing relationships among angiosperm species. The function of the flower is to ensure fertilization of the ovule and development of fruit containing seeds. The floral apparatus may arise terminally on a shoot or from the axil of a leaf (where the petiole attaches to the stem). Occasionally, as in violets, a flower arises singly in the axil of an ordinary foliage-leaf. More typically, the flower-bearing portion of the plant is sharply distinguished from the foliage-bearing or vegetative portion, and forms a more or less elaborate branch-system called an inflorescence.

qas: question: What is a willow's flower comprised of?
answers: text: only a few stamens or two carpels
is_impossible: no

question: What have some structures evolved to protect?
answers: text: the sporophylls
is_impossible: no

question: Individual members of enveloping structures are known by what terms?
answers: text: sepals and petals
is_impossible: no

question: What appearance are calyx of sepals typically?
answers: text: green and leaf-like
is_impossible: no

question: The features of flowers which attract pollinators also attract what other creature?
answers: text: humans
is_impossible: no

question: What do sporophylls form that is attractive to pollinators?
is_impossible: yes

question: In what flower are stamens and sporophylls not able to be distinguished from each other?
is_impossible: yes

question: What do corolla of petals function to protect?
is_impossible: yes

question: What color is the more delicate willow?
is_impossible: yes

question: What characteristics of the flower attract sporophylls?
is_impossible: yes
context: The flower may consist only of these parts, as in willow, where each flower comprises only a few stamens or two carpels. Usually, other structures are present and serve to protect the sporophylls and to form an envelope attractive to pollinators. The individual members of these surrounding structures are known as sepals and petals (or tepals in flowers such as Magnolia where sepals and petals are not distinguishable from each other). The outer series (calyx of sepals) is usually green and leaf-like, and functions to protect the rest of the flower, especially the bud. The inner series (corolla of petals) is, in general, white or brightly colored, and is more delicate in structure. It functions to attract insect or bird pollinators. Attraction is effected by color, scent, and nectar, which may be secreted in some part of the flower. The characteristics that attract pollinators account for the popularity of flowers and flowering plants among humans.

qas: question: What sexual feature do a majority of flowers demonstrate?
answers: text: hermaphrodite
is_impossible: no

question: Why did flowering plants develop numerous morphological and physiological mechanisms?
answers: text: reduce or prevent self-fertilization
is_impossible: no

question: Why are a heteromorphic flower's carpels and stamens different lengths?
answers: text: so animal pollinators cannot easily transfer pollen to the pistil
is_impossible: no

question: What type of mechanism might homomorphic flowers use to tell the difference between foreign and self pollen grains?
answers: text: biochemical
is_impossible: no

question: How are some male and female parts separated for some species?
answers: text: different flowers
is_impossible: no

question: What feature do a majority of biochemical mechanisms have?
is_impossible: yes

question: What do hermaphrodite flowers use to discriminate between self and non-self pollination?
is_impossible: yes

question: What happens to male and female parts of carpels that are hermaphrodites?
is_impossible: yes

question: Why did long stamens develop numerous morphological and physiological mechanisms?
is_impossible: yes

question: What do homomorphic flowers have to make it harder to be pollinated by animals?
is_impossible: yes
context: While the majority of flowers are perfect or hermaphrodite (having both pollen and ovule producing parts in the same flower structure), flowering plants have developed numerous morphological and physiological mechanisms to reduce or prevent self-fertilization. Heteromorphic flowers have short carpels and long stamens, or vice versa, so animal pollinators cannot easily transfer pollen to the pistil (receptive part of the carpel). Homomorphic flowers may employ a biochemical (physiological) mechanism called self-incompatibility to discriminate between self and non-self pollen grains. In other species, the male and female parts are morphologically separated, developing on different flowers.

qas: question: What process does double fertilization refer to?
answers: text: two sperm cells fertilize cells in the ovary
is_impossible: no

question: What does a pollen grain adhere to, to start the process of double fertilization?
answers: text: the stigma of the pistil
is_impossible: no

question: What type of cell travels down the pollen tube while it's growing?
answers: text: haploid generative
is_impossible: no

question: Where does the pollen tube release its sperm cells?
answers: text: one of the synergids
is_impossible: no

question: What serves as the embryo's food supply?
answers: text: endosperm
is_impossible: no

question: When a pollen tube fertilizes cells in the ovary, what is it called?
is_impossible: yes

question: What begins the process of synergid?
is_impossible: yes

question: What does a sperm cell adhere to to start double fertilization?
is_impossible: yes

question: What degenerates as a pollen grain adheres to the stigma?
is_impossible: yes

question: What does the zygote fuse with to produce a triploid?
is_impossible: yes
context: Double fertilization refers to a process in which two sperm cells fertilize cells in the ovary. This process begins when a pollen grain adheres to the stigma of the pistil (female reproductive structure), germinates, and grows a long pollen tube. While this pollen tube is growing, a haploid generative cell travels down the tube behind the tube nucleus. The generative cell divides by mitosis to produce two haploid (n) sperm cells. As the pollen tube grows, it makes its way from the stigma, down the style and into the ovary. Here the pollen tube reaches the micropyle of the ovule and digests its way into one of the synergids, releasing its contents (which include the sperm cells). The synergid that the cells were released into degenerates and one sperm makes its way to fertilize the egg cell, producing a diploid (2n) zygote. The second sperm cell fuses with both central cell nuclei, producing a triploid (3n) cell. As the zygote develops into an embryo, the triploid cell develops into the endosperm, which serves as the embryo's food supply. The ovary now will develop into fruit and the ovule will develop into seed.

qas: question: The appearance of the seed coat bears a definite relation to that of what?
answers: text: the fruit
is_impossible: no

question: What does the seed coat protect?
answers: text: embryo
is_impossible: no

question: What does the fruit of the flower secure?
answers: text: dissemination
is_impossible: no

question: How developed is the seed coat when it's used for dissemination?
answers: text: slightly
is_impossible: no

question: What is the embryo character related to?
is_impossible: yes

question: What do dehiscent fruits directly promote?
is_impossible: yes

question: What does the exposed seed protect?
is_impossible: yes

question: What does the embryo in an indehiscent fruit secure?
is_impossible: yes

question: What must a indehiscent fruit do that is usually done by the fruit?
is_impossible: yes
context: The character of the seed coat bears a definite relation to that of the fruit. They protect the embryo and aid in dissemination; they may also directly promote germination. Among plants with indehiscent fruits, in general, the fruit provides protection for the embryo and secures dissemination. In this case, the seed coat is only slightly developed. If the fruit is dehiscent and the seed is exposed, in general, the seed-coat is well developed, and must discharge the functions otherwise executed by the fruit.

qas: question: On what is agriculture almost completely dependent?
answers: text: angiosperms
is_impossible: no

question: What family of plants is most important for human sustenance?
answers: text: Poaceae
is_impossible: no

question: What is the more common name of the Fabaceae?
answers: text: legume
is_impossible: no

question: What family do potatoes, tomatoes and peppers belong to?
answers: text: Solanaceae
is_impossible: no

question: What family would you find cherries in?
answers: text: Rosaceae
is_impossible: no

question: What does the legume family provide as the most important of all the plant families?
is_impossible: yes

question: What is the more common name of the Solanaceae family that is second place?
is_impossible: yes

question: What does the rue family provide that is needed for livestock?
is_impossible: yes

question: What are some examples of what the nightshade family provides as the most important group?
is_impossible: yes

question: What does the rue family provide that makes it one group of high importance?
is_impossible: yes
context: Agriculture is almost entirely dependent on angiosperms, which provide virtually all plant-based food, and also provide a significant amount of livestock feed. Of all the families of plants, the Poaceae, or grass family (grains), is by far the most important, providing the bulk of all feedstocks (rice, corn — maize, wheat, barley, rye, oats, pearl millet, sugar cane, sorghum). The Fabaceae, or legume family, comes in second place. Also of high importance are the Solanaceae, or nightshade family (potatoes, tomatoes, and peppers, among others), the Cucurbitaceae, or gourd family (also including pumpkins and melons), the Brassicaceae, or mustard plant family (including rapeseed and the innumerable varieties of the cabbage species Brassica oleracea), and the Apiaceae, or parsley family. Many of our fruits come from the Rutaceae, or rue family (including oranges, lemons, grapefruits, etc.), and the Rosaceae, or rose family (including apples, pears, cherries, apricots, plums, etc.).

qas: question: What do monocots usually have two of within each seed?
is_impossible: yes

question: According to the Cronquist system how is the number of cotyledons viewed?
is_impossible: yes

question: What other descriptive names are allowed by the English system?
is_impossible: yes

question: How many groups are flowering plants divided into in the English system?
is_impossible: yes

question: What is one group that is used under the English system?
is_impossible: yes
context: Traditionally, the flowering plants are divided into two groups, which in the Cronquist system are called Magnoliopsida (at the rank of class, formed from the family name Magnoliaceae) and Liliopsida (at the rank of class, formed from the family name Liliaceae). Other descriptive names allowed by Article 16 of the ICBN include Dicotyledones or Dicotyledoneae, and Monocotyledones or Monocotyledoneae, which have a long history of use. In English a member of either group may be called a dicotyledon (plural dicotyledons) and monocotyledon (plural monocotyledons), or abbreviated, as dicot (plural dicots) and monocot (plural monocots). These names derive from the observation that the dicots most often have two cotyledons, or embryonic leaves, within each seed. The monocots usually have only one, but the rule is not absolute either way. From a diagnostic point of view, the number of cotyledons is neither a particularly handy nor a reliable character.