id stringlengths 24 24 | question stringlengths 1 270 | answer stringlengths 1 239 | documents listlengths 1 1 |
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57304a52069b531400831ff2 | What is also increased along with the antenna's height? | lobes | [
"Antenna_(radio)\n\nFor horizontal propagation between transmitting and receiving antennas situated near the ground reasonably far from each other, the distances traveled by tne direct and reflected rays are nearly the same. There is almost no relative phase shift. If the emission is polarized vertically, the two f... |
57304bf5069b531400832013 | What is another name for classical television transmissions? | analog | [
"Antenna_(radio)\n\nOn the other hand, classical (analog) television transmissions are usually horizontally polarized, because in urban areas buildings can reflect the electromagnetic waves and create ghost images due to multipath propagation. Using horizontal polarization, ghosting is reduced because the amount of... |
57304bf5069b531400832014 | Buildings can create ghost images because of what? | multipath propagation | [
"Antenna_(radio)\n\nOn the other hand, classical (analog) television transmissions are usually horizontally polarized, because in urban areas buildings can reflect the electromagnetic waves and create ghost images due to multipath propagation. Using horizontal polarization, ghosting is reduced because the amount of... |
57304bf5069b531400832015 | When is ghosting reduced? | horizontal polarization | [
"Antenna_(radio)\n\nOn the other hand, classical (analog) television transmissions are usually horizontally polarized, because in urban areas buildings can reflect the electromagnetic waves and create ghost images due to multipath propagation. Using horizontal polarization, ghosting is reduced because the amount of... |
57304bf5069b531400832016 | What cause less problems in digital terrestrial television? | Vertically polarized analog television | [
"Antenna_(radio)\n\nOn the other hand, classical (analog) television transmissions are usually horizontally polarized, because in urban areas buildings can reflect the electromagnetic waves and create ghost images due to multipath propagation. Using horizontal polarization, ghosting is reduced because the amount of... |
57304eac8ab72b1400f9c41c | Where are the indiviual array elements known? | antenna arrays | [
"Antenna_(radio)\n\nCurrent circulating in one antenna generally induces a voltage across the feedpoint of nearby antennas or antenna elements. The mathematics presented below are useful in analyzing the electrical behaviour of antenna arrays, where the properties of the individual array elements (such as half wave... |
57304eac8ab72b1400f9c41d | What induces a feedpoint to antennas nearby? | Current circulating | [
"Antenna_(radio)\n\nCurrent circulating in one antenna generally induces a voltage across the feedpoint of nearby antennas or antenna elements. The mathematics presented below are useful in analyzing the electrical behaviour of antenna arrays, where the properties of the individual array elements (such as half wave... |
57304eac8ab72b1400f9c41e | What are the mathmatic useful towards? | electrical behaviour | [
"Antenna_(radio)\n\nCurrent circulating in one antenna generally induces a voltage across the feedpoint of nearby antennas or antenna elements. The mathematics presented below are useful in analyzing the electrical behaviour of antenna arrays, where the properties of the individual array elements (such as half wave... |
57304eac8ab72b1400f9c41f | What cause mutual interactions between the elements electric and magnetic fields? | proximity | [
"Antenna_(radio)\n\nCurrent circulating in one antenna generally induces a voltage across the feedpoint of nearby antennas or antenna elements. The mathematics presented below are useful in analyzing the electrical behaviour of antenna arrays, where the properties of the individual array elements (such as half wave... |
573051562461fd1900a9cd1d | a antenna element not connected to anything is circuited how? | open circuited | [
"Antenna_(radio)\n\nThis is a consequence of Lorentz reciprocity. For an antenna element not connected to anything (open circuited) one can write . But for an element which is short circuited, a current is generated across that short but no voltage is allowed, so the corresponding . This is the case, for instance... |
573051562461fd1900a9cd1e | When is the element not allowed voltage? | short circuited | [
"Antenna_(radio)\n\nThis is a consequence of Lorentz reciprocity. For an antenna element not connected to anything (open circuited) one can write . But for an element which is short circuited, a current is generated across that short but no voltage is allowed, so the corresponding . This is the case, for instance... |
573051562461fd1900a9cd1f | What element absorbs and reradiate RF-energy? | Parasitic | [
"Antenna_(radio)\n\nThis is a consequence of Lorentz reciprocity. For an antenna element not connected to anything (open circuited) one can write . But for an element which is short circuited, a current is generated across that short but no voltage is allowed, so the corresponding . This is the case, for instance... |
573051562461fd1900a9cd20 | What antenna can the solid rod be viewed as a dipole antenna? | Yagi-Uda | [
"Antenna_(radio)\n\nThis is a consequence of Lorentz reciprocity. For an antenna element not connected to anything (open circuited) one can write . But for an element which is short circuited, a current is generated across that short but no voltage is allowed, so the corresponding . This is the case, for instance... |
573051562461fd1900a9cd21 | Where can this solid rod be viewed? | feedpoint | [
"Antenna_(radio)\n\nThis is a consequence of Lorentz reciprocity. For an antenna element not connected to anything (open circuited) one can write . But for an element which is short circuited, a current is generated across that short but no voltage is allowed, so the corresponding . This is the case, for instance... |
57306bf68ab72b1400f9c4da | What type of programmin relies on vertical polarization? | broadcasting | [
"Antenna_(radio)\n\nThe difference in the above factors for the case of θ=0 is the reason that most broadcasting (transmissions intended for the public) uses vertical polarization. For receivers near the ground, horizontally polarized transmissions suffer cancellation. For best reception the receiving antennas for ... |
57306bf68ab72b1400f9c4db | If you were to position your receiver closer to the ground what might be a negative of this placement? | cancellation | [
"Antenna_(radio)\n\nThe difference in the above factors for the case of θ=0 is the reason that most broadcasting (transmissions intended for the public) uses vertical polarization. For receivers near the ground, horizontally polarized transmissions suffer cancellation. For best reception the receiving antennas for ... |
57306bf68ab72b1400f9c4dc | What is one use that would require an antenna to receive signals in various ways at once? | mobile phones | [
"Antenna_(radio)\n\nThe difference in the above factors for the case of θ=0 is the reason that most broadcasting (transmissions intended for the public) uses vertical polarization. For receivers near the ground, horizontally polarized transmissions suffer cancellation. For best reception the receiving antennas for ... |
57306bf68ab72b1400f9c4dd | If you were to develop a signal to be used with mobile phones what would be an effective antenna type? | circular polarization. | [
"Antenna_(radio)\n\nThe difference in the above factors for the case of θ=0 is the reason that most broadcasting (transmissions intended for the public) uses vertical polarization. For receivers near the ground, horizontally polarized transmissions suffer cancellation. For best reception the receiving antennas for ... |
57306bf68ab72b1400f9c4de | What would the antenna you are using take advantage of to allow it to work in multiple locations? | mixed polarization | [
"Antenna_(radio)\n\nThe difference in the above factors for the case of θ=0 is the reason that most broadcasting (transmissions intended for the public) uses vertical polarization. For receivers near the ground, horizontally polarized transmissions suffer cancellation. For best reception the receiving antennas for ... |
57306d712461fd1900a9ce0b | What type of antenna can be formed by a circular segment of wire? | Loop antennas | [
"Antenna_(radio)\n\nLoop antennas consist of a loop or coil of wire. Loops with circumference of a wavelength or larger act similarly to dipole antennas. However loops small in comparison to a wavelength act differently. They interact with the magnetic field of the radio wave instead of the electric field as other ... |
57306d712461fd1900a9ce0c | What is a loop antenna compared with to determine its beahvior? | circumference of a wavelength | [
"Antenna_(radio)\n\nLoop antennas consist of a loop or coil of wire. Loops with circumference of a wavelength or larger act similarly to dipole antennas. However loops small in comparison to a wavelength act differently. They interact with the magnetic field of the radio wave instead of the electric field as other ... |
57306d712461fd1900a9ce0d | If you needed to place an antenna somewhere with a large amount of interference, which type would be best? | loops small | [
"Antenna_(radio)\n\nLoop antennas consist of a loop or coil of wire. Loops with circumference of a wavelength or larger act similarly to dipole antennas. However loops small in comparison to a wavelength act differently. They interact with the magnetic field of the radio wave instead of the electric field as other ... |
57306d712461fd1900a9ce0e | Why would this type be good for receiving but not transmtting? | low radiation resistance | [
"Antenna_(radio)\n\nLoop antennas consist of a loop or coil of wire. Loops with circumference of a wavelength or larger act similarly to dipole antennas. However loops small in comparison to a wavelength act differently. They interact with the magnetic field of the radio wave instead of the electric field as other ... |
57306d712461fd1900a9ce0f | What else would be an effective application of this antenna type? | direction finding | [
"Antenna_(radio)\n\nLoop antennas consist of a loop or coil of wire. Loops with circumference of a wavelength or larger act similarly to dipole antennas. However loops small in comparison to a wavelength act differently. They interact with the magnetic field of the radio wave instead of the electric field as other ... |
57306e47069b5314008320cf | Are essential properties of an antenna changed based on what fungtion they are performing | the same | [
"Antenna_(radio)\n\nIt is a fundamental property of antennas that the electrical characteristics of an antenna described in the next section, such as gain, radiation pattern, impedance, bandwidth, resonant frequency and polarization, are the same whether the antenna is transmitting or receiving. For example, the \"... |
57306e47069b5314008320d0 | What proposition explains the equivalency of the recieving pattern of an antenna? | reciprocity theorem of electromagnetics | [
"Antenna_(radio)\n\nIt is a fundamental property of antennas that the electrical characteristics of an antenna described in the next section, such as gain, radiation pattern, impedance, bandwidth, resonant frequency and polarization, are the same whether the antenna is transmitting or receiving. For example, the \"... |
57306e47069b5314008320d1 | Can the antenna serve more than one fungtion at a time? | either transmitting or receiving | [
"Antenna_(radio)\n\nIt is a fundamental property of antennas that the electrical characteristics of an antenna described in the next section, such as gain, radiation pattern, impedance, bandwidth, resonant frequency and polarization, are the same whether the antenna is transmitting or receiving. For example, the \"... |
57306e47069b5314008320d2 | What is one electrical trait of an antenna? | radiation pattern | [
"Antenna_(radio)\n\nIt is a fundamental property of antennas that the electrical characteristics of an antenna described in the next section, such as gain, radiation pattern, impedance, bandwidth, resonant frequency and polarization, are the same whether the antenna is transmitting or receiving. For example, the \"... |
572ef96cdfa6aa1500f8d50d | What are the most diverse group of land plants? | angiosperms | [
"Flowering_plant\n\nThe 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... |
572ef96cdfa6aa1500f8d50e | How many species of flowering plants are there about? | 350,000 | [
"Flowering_plant\n\nThe 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... |
572ef96cdfa6aa1500f8d50f | What do angiosperms have in common with gymnosperms? | seed-producing plants | [
"Flowering_plant\n\nThe 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... |
572ef96cdfa6aa1500f8d510 | What does an angiosperm produce its seeds within? | an enclosure | [
"Flowering_plant\n\nThe 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... |
572ef96cdfa6aa1500f8d511 | What is the Greek word for "case" or "casing"? | angeion | [
"Flowering_plant\n\nThe 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... |
572efadd03f9891900756b09 | How long have higher plants lived on land? | at least 475 million years | [
"Flowering_plant\n\nFossilized 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 ... |
572efadd03f9891900756b0a | How did early plants reproduce sexually? | with flagellated, swimming sperm | [
"Flowering_plant\n\nFossilized 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 ... |
572efadd03f9891900756b0b | Upright meisporangia allowed what to be dispersed to new habitats? | spores | [
"Flowering_plant\n\nFossilized 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 ... |
572efadd03f9891900756b0c | What are the nearest algal relatives existing today? | Charophycean green algae | [
"Flowering_plant\n\nFossilized 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 ... |
572efadd03f9891900756b0d | What is the common name for Selaginella? | the spike-moss | [
"Flowering_plant\n\nFossilized 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 ... |
572efb9cc246551400ce4820 | What did Charles Darwin call the sudden appearance of nearly modern flowers in the fossil record? | abominable mystery | [
"Flowering_plant\n\nThe 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 disco... |
572efb9cc246551400ce4821 | What type of fossil is the recently discovered Archaefructus? | angiosperm | [
"Flowering_plant\n\nThe 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 disco... |
572efb9cc246551400ce4822 | What fossil evidence is lacking when it comes to flowers? | evidence showing exactly how flowers evolved | [
"Flowering_plant\n\nThe 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 disco... |
572efb9cc246551400ce4823 | From what period does fossilized pollen suggest an older date for angiosperm origin? | Middle Triassic | [
"Flowering_plant\n\nThe 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 disco... |
572efb9cc246551400ce4824 | What relationship proposed on the basis of morphological evidence has recently been disputed? | relationship between angiosperms and gnetophytes | [
"Flowering_plant\n\nThe 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 disco... |
572efc3503f9891900756b13 | How many distinct rounds of genome duplication events are suspected in the evolution of seed plants? | two | [
"Flowering_plant\n\nThe 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 a... |
572efc3503f9891900756b14 | When did the first whole genome duplication event occur? | 319 million years ago | [
"Flowering_plant\n\nThe 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 a... |
572efc3503f9891900756b15 | What type of event perhaps created the line which led to modern flowering plants? | whole genome duplication | [
"Flowering_plant\n\nThe 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 a... |
572efc3503f9891900756b16 | How are duplication events studied? | by sequencing the genome of an ancient flowering plant | [
"Flowering_plant\n\nThe 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 a... |
572efc3503f9891900756b17 | Who coined the term "abominable mystery"? | Darwin | [
"Flowering_plant\n\nThe 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 a... |
572f1c4203f9891900756b99 | When is the earliest known macrofossil identified as an angiosperm dated? | about 125 million years BP | [
"Flowering_plant\n\nThe 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... |
572f1c4203f9891900756b9a | What is the earliest known angiosperm? | Archaefructus liaoningensis | [
"Flowering_plant\n\nThe 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... |
572f1c4203f9891900756b9b | What pushes the age of angiosperm 5 million years further back? | pollen | [
"Flowering_plant\n\nThe 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... |
572f1c4203f9891900756b9c | How long ago has circumstantial evidence has been found for the existence of angiosperms? | 250 million years ago | [
"Flowering_plant\n\nThe 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... |
572f1c4203f9891900756b9d | What group of now extinct seed plants had many of the traits of what are now flowering plants? | Gigantopterids | [
"Flowering_plant\n\nThe 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... |
572f3442b2c2fd1400567f81 | When does a great diversity of angiosperms appear in the fossil record? | approximately 100 million years ago | [
"Flowering_plant\n\nThe 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 Chloranthace... |
572f3442b2c2fd1400567f82 | What is the appearance of a large amount of angiosperms in the fossil record known as? | great angiosperm radiation, | [
"Flowering_plant\n\nThe 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 Chloranthace... |
572f3442b2c2fd1400567f83 | When did the division of the eight main groups of angiosperms occur? | 40 million years ago | [
"Flowering_plant\n\nThe 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 Chloranthace... |
572f3442b2c2fd1400567f84 | What were the angiosperms up to by the late Cretaceous? | dominated environments | [
"Flowering_plant\n\nThe 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 Chloranthace... |
572f3442b2c2fd1400567f85 | Beech and maple had already appeared by what period? | Cretaceous | [
"Flowering_plant\n\nThe 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 Chloranthace... |
572f376004bcaa1900d76789 | What is one proposed explanation for the instant appearance of flowering plants? | Island genetics | [
"Flowering_plant\n\nIsland 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. Fl... |
572f376004bcaa1900d7678a | What is island genetics thought to be a default source of? | speciation | [
"Flowering_plant\n\nIsland 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. Fl... |
572f376004bcaa1900d7678b | What did radical adaptations seem to have required? | inferior transitional forms | [
"Flowering_plant\n\nIsland 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. Fl... |
572f376004bcaa1900d7678c | How did an isolated setting like an island help flowering plants evolve? | highly specialized relationship with some specific animal | [
"Flowering_plant\n\nIsland 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. Fl... |
572f376004bcaa1900d7678d | What are bees descended from? | wasps | [
"Flowering_plant\n\nIsland 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. Fl... |
572f39d804bcaa1900d7679d | What are animals also a part of? | distribution of seeds | [
"Flowering_plant\n\nAnimals 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 mutualist... |
572f39d804bcaa1900d7679e | What did the enlargement of flower parts evolve to form? | Fruit | [
"Flowering_plant\n\nAnimals 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 mutualist... |
572f39d804bcaa1900d7679f | What does a plant get out of forming fruit? | seed-dispersal | [
"Flowering_plant\n\nAnimals 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 mutualist... |
572f39d804bcaa1900d767a0 | What are many mutualistic relationships, thus failing to survive competition? | fragile | [
"Flowering_plant\n\nAnimals 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 mutualist... |
572f39d804bcaa1900d767a1 | What turned out to be unusually effective for plants to reproduce? | flowering | [
"Flowering_plant\n\nAnimals 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 mutualist... |
572f3c9604bcaa1900d767a7 | What uses a combination of genes to form new shoots? | Flower ontogeny | [
"Flowering_plant\n\nFlower 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, thi... |
572f3c9604bcaa1900d767a8 | What were plant parts like in their primitive days? | separate from (but in contact with) each other | [
"Flowering_plant\n\nFlower 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, thi... |
572f3c9604bcaa1900d767a9 | How did flowers become bixsexual? | grow in a spiral pattern | [
"Flowering_plant\n\nFlower 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, thi... |
572f3c9604bcaa1900d767aa | What did some plant parts do as they evolved? | fused together | [
"Flowering_plant\n\nFlower 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, thi... |
572f3c9604bcaa1900d767ab | What is a term for a plant with a specific sex per flower? | "ovary-inferior" | [
"Flowering_plant\n\nFlower 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, thi... |
572f3e7d04bcaa1900d767bb | How long has flower evolution occurred? | present day | [
"Flowering_plant\n\nFlower 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 ... |
572f3e7d04bcaa1900d767bc | Humans have effected some flowers so much they can no longer do what in nature? | pollinated | [
"Flowering_plant\n\nFlower 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 ... |
572f3e7d04bcaa1900d767bd | What heritage do many modern domesticated flower species have? | formerly simple weeds | [
"Flowering_plant\n\nFlower 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 ... |
572f3e7d04bcaa1900d767be | Why did weeds grow with human crops? | symbiotic companion plant relationships | [
"Flowering_plant\n\nFlower 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 ... |
572f3e7d04bcaa1900d767bf | What feature helped flowers not get plucked? | prettiest | [
"Flowering_plant\n\nFlower 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 ... |
572f4374947a6a140053c832 | What three groups were the first to diverge from angiosperm? | Amborellales, Nymphaeales, and Austrobaileyales | [
"Flowering_plant\n\nThe 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 ... |
572f4374947a6a140053c833 | What term refers to the first three groups to diverge from angiosperm? | basal | [
"Flowering_plant\n\nThe 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 ... |
572f4374947a6a140053c834 | How clear is the relationship between the broadest of the three non-basal angiosperm groups? | unclear | [
"Flowering_plant\n\nThe 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 ... |
572f4374947a6a140053c835 | What group do some analyses seem to indicate diverged first? | magnoliids | [
"Flowering_plant\n\nThe 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 ... |
572f4440947a6a140053c83a | What term did Paul Hermann come up with in 1690? | Angiosperm | [
"Flowering_plant\n\nThe 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 ... |
572f4440947a6a140053c83b | What did Hermann use the term angiosperm a primary division of in the plant kingdom? | primary | [
"Flowering_plant\n\nThe 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 ... |
572f4440947a6a140053c83c | Who restricted the application of the angiosperm term? | Carl Linnaeus | [
"Flowering_plant\n\nThe 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 ... |
572f4440947a6a140053c83d | What did Robert Brown establish the existence of in Cycadeae and Coniferae? | naked ovules | [
"Flowering_plant\n\nThe 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 ... |
572f4440947a6a140053c83e | What is the group-name angiosperm has been used for by botanical writers? | other dicotyledonous plants | [
"Flowering_plant\n\nThe 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 ... |
572f44e8b2c2fd1400567fb3 | In taxonomies, what type of group are flowering plants treated? | coherent | [
"Flowering_plant\n\nIn 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... |
572f44e8b2c2fd1400567fb4 | What does anthophyta mean? | flowering plants | [
"Flowering_plant\n\nIn 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... |
572f44e8b2c2fd1400567fb5 | What do the Wettstein and Engler systems use at the assigned rank of subdivision? | Angiospermae | [
"Flowering_plant\n\nIn 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... |
572f44e8b2c2fd1400567fb6 | How does the APG system of 1998, with its 2003 and 2009 revisions, treat flowering plants? | a clade called angiosperms | [
"Flowering_plant\n\nIn 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... |
572f44e8b2c2fd1400567fb7 | What formal subclass classification were flowering plants given in 2009? | Magnoliidae | [
"Flowering_plant\n\nIn 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... |
572f45a004bcaa1900d76805 | What internal component has undergone considerable revision? | classification | [
"Flowering_plant\n\nThe 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 pl... |
572f45a004bcaa1900d76806 | What system did Arthur Cronquist put forth in 1968, but not publish in full form until 1981? | The Cronquist system | [
"Flowering_plant\n\nThe 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 pl... |
572f45a004bcaa1900d76807 | What consensus is the AGP trying to reach? | how the flowering plants should be arranged | [
"Flowering_plant\n\nThe 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 pl... |
572f45a004bcaa1900d76808 | Who published an influential reclassification of the angiosperms in 1998? | APG | [
"Flowering_plant\n\nThe 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 pl... |
572f46d8947a6a140053c852 | What type of groups do monocots form, based on a recent APG studies? | monophyletic | [
"Flowering_plant\n\nRecent 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... |
572f46d8947a6a140053c853 | Eudicots or tricolpates are part of a monophyletic group formed by what species? | dicot | [
"Flowering_plant\n\nRecent 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... |
572f46d8947a6a140053c854 | What third major clade can many dicot species be found in? | magnoliids | [
"Flowering_plant\n\nRecent 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... |
572f46d8947a6a140053c855 | How many species dicot species are magnoliids? | about 9,000 | [
"Flowering_plant\n\nRecent 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... |
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