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Plant Nutrition | Plants | Biology | FuseSchool
Where do plants get their food from? Remember they are autotrophic, plants make their own food through the process of photosynthesis. In order to make all of the macromolecules, the plant needs to obtain some other elements from the soil. For example, Nitrogen is needed to make protein. As you know Nitrogen is needed to make protein, so without this element the plant will have stunted growth.
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托福TPO/Official 5 Passage 1阅读原文题目答案及解析 – 出国留学
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주제와 관련된 더 많은 사진을 참조하십시오 Plant Nutrition | Plants | Biology | FuseSchool. 댓글에서 더 많은 관련 이미지를 보거나 필요한 경우 더 많은 관련 기사를 볼 수 있습니다.
주제에 대한 기사 평가 minerals and plants toefl
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- Date Published: 2020. 2. 25.
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TOEFL reading test 9 with answers
Ancient Rome and Greece There is a quality of cohesiveness about the Roman world that applied neither to Greece nor perhaps to any other civilization, ancient or modern. Like the stone of Roman wall, which were held together both by the regularity of the design and by that peculiarly powerful Roman cement, so the various parts of the Roman realm were bonded into a massive, monolithic entity by physical, organizational, and psychological controls . The physical bonds included the network of military garrisons, which were stationed in every province, and the network of stone-built roads that linked the provinces with Rome. The organizational bonds were based on the common principles of law and administration and on the universal army of officials who enforced common standards of conduct. The psychological controls were built on fear and punishment on the absolute certainty that anyone or anything that threatened the authority of Rome would be utterly destroyed. The source of Ro
TOEFL TPO 5-1 Minerals and Plants Flashcards
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InventorAcademy.com.cn brings you the list of words for the TOEFL reading passage TPO 5-1 Minerals and Plants. For other amazing TOEFL materials, strategy guides, and expert tips; visit our website at inventoracademy.com.cn.
TOEFL iBT | Reading | 1 on 1 Coaching | Time-management & Vocabulary | Minerals & Plants
BOOM! We’re back with the first of its kind! I actually have another one scheduled to upload but not for a few months. Nonetheless, this is a full coaching session from one of my students, and in today’s coaching, I cover three main areas while walking her through a passage: time-management, double-checking vocabulary, and the before/after. There are lots of great techniques that could be used throughout this podcast (down below).
MINERALS AND PLANTS
1) Research has shown that certain minerals are required by plants for normal growth and development. The soil is the source of these minerals, which are absorbed by the plant with the water from the soil. Even nitrogen, which is a gas in its elemental state, is normally absorbed from the soil as nitrate ions. Some soils are notoriously deficient in micro nutrients and are therefore unable to support most plant life. So-called serpentine soils, for example, are deficient in calcium, and only plants able to tolerate low levels of this mineral can survive. In modern agriculture, mineral depletion of soils is a major concern, since harvesting crops interrupts the recycling of nutrients back to the soil.
2) Mineral deficiencies can often be detected by specific symptoms such as chlorosis (loss of chlorophyll resulting in yellow or white leaf tissue), necrosis (isolated dead patches), anthocyanin formation (development of deep red pigmentation of leaves or stem), stunted growth, and development of woody tissue in an herbaceous plant. Soils are most commonly deficient in nitrogen and phosphorus. Nitrogen-deficient plants exhibit many of the symptoms just described. Leaves develop chlorosis; stems are short and slender; and anthocyanin discoloration occurs on stems, petioles, and lower leaf surfaces. Phosphorus-deficient plants are often stunted, with leaves turning a characteristic dark green, often with the accumulation of anthocyanin. Typically, older leaves are affected first as the phosphorus is mobilized to young growing tissue. Iron deficiency is characterized by chlorosis between veins in young leaves.
3) Much of the research on nutrient deficiencies is based on growing plants hydroponically, that is, in soilless liquid nutrient solutions. This technique allows researchers to create solutions that selectively omit certain nutrients and then observe the resulting effects on the plants. Hydroponics has applications beyond basic research, since it facilitates the growing of greenhouse vegetables during winter. Aeroponics, a technique in which plants are suspended and the roots misted with a nutrient solution, is another method for growing plants without soil.
4) While mineral deficiencies can limit the growth of plants, an overabundance of certain minerals can be toxic and can also limit growth. Saline soils, which have high concentrations of sodium chloride and other salts, limit plant growth, and research continues to focus on developing salt-tolerant varieties of agricultural crops. Research has focused on the toxic effects of heavy metals such as lead, cadmium, mercury, and aluminum; however, even copper and zinc, which are essential elements, can become toxic in high concentrations. Although most plants cannot survive in these soils, certain plants have the ability to tolerate high levels of these minerals.
5) Scientists have known for some time that certain plants, called hyper accumulators, can concentrate minerals at levels a hundredfold or greater than normal. A survey of known hyper accumulators identified that 75 percent of them amassed nickel; cobalt, copper, zinc, manganese, lead, and cadmium are other minerals of choice. Hyper accumulators run the entire range of the plant world. They may be herbs, shrubs, or trees. Many members of the mustard family, spurge family, legume family, and grass family are top hyperaccumulators. Many are found in tropical and subtropical areas of the world, where accumulation of high concentrations of metals may afford some protection against plant-eating insects and microbial pathogens.
6) Only recently have investigators considered using these plants to clean up soil and waste sites that have been contaminated by toxic levels of heavy metals—an environmentally friendly approach known as phytoremediation. This scenario begins with the planting of hyperaccumulating species in the target area, such as an abandoned mine or an irrigation pond contaminated by runoff. Toxic minerals would first be absorbed by roots but later relocated to the stem and leaves. A harvest of the shoots would remove the toxic compounds off site to be burned or composted to recover the metal for industrial uses. After several years of cultivation and harvest, the site would be restored at a cost much lower than the price of excavation and reburial, the standard practice for remediation of contaminated soils. For example, in field trials, the plant alpine pennycress removed zinc and cadmium from soils near a zinc smelter, and Indian mustard, native to Pakistan and India, has been effective in reducing levels of selenium salts by 50 percent in contaminated soils.
Directions: Now answer the questions.
PARAGRAPH 1
Research has shown that certain minerals are required by plants for normal growth and development. The soil is the source of these minerals, which are absorbed by the plant with the water from the soil. Even nitrogen, which is a gas in its elemental state, is normally absorbed from the soil as nitrate ions. Some soils are notoriously deficient in micro nutrients and are therefore unable to support most plant life. So-called serpentine soils, for example, are deficient in calcium, and only plants able to tolerate low levels of this mineral can survive. In modern agriculture, mineral depletion of soils is a major concern, since harvesting crops interrupts the recycling of nutrients back to the soil.
1. According to paragraph 1, what is true of plants that can grow in serpentine soils?
They absorb micronutrients unusually well.
They require far less calcium than most plants do.
They are able to absorb nitrogen in its elemental state.
They are typically crops raised for food.
PARAGRAPH 2
Mineral deficiencies can often be detected by specific symptoms such as chlorosis (loss of chlorophyll resulting in yellow or white leaf tissue), necrosis (isolated dead patches), anthocyanin formation (development of deep red pigmentation of leaves or stem), stunted growth, and development of woody tissue in an herbaceous plant. Soils are most commonly deficient in nitrogen and phosphorus. Nitrogen-deficient plants exhibit many of the symptoms just described. Leaves develop chlorosis; stems are short and slender; and anthocyanin discoloration occurs on stems, petioles, and lower leaf surfaces. Phosphorus-deficient plants are often stunted, with leaves turning a characteristic dark green, often with the accumulation of anthocyanin. Typically, older leaves are affected first as the phosphorus is mobilized to young growing tissue. Iron deficiency is characterized by chlorosis between veins in young leaves.
The word “exhibit” in the passage is closest in meaning to
fight off
show
cause
spread
According to paragraph 2, which of the following symptoms occurs in phosphorus-deficient plants but not in plants deficient in nitrogen or iron?
chlorosis on leaves
change in leaf pigmentation to a dark shade of green
Short, stunted appearance of stems
Reddish pigmentation on the leaves or stem
According to paragraph 2, a symptom of iron deficiency is the presence in young leaves of
deep red discoloration between the veins
white or yellow tissue between the veins
dead spots between the veins
characteristic dark green veins
PARAGRAPH 3
Much of the research on nutrient deficiencies is based on growing plants hydroponically, that is, in soilless liquid nutrient solutions. This technique allows researchers to create solutions that selectively omit certain nutrients and then observe the resulting effects on the plants. Hydroponics has applications beyond basic research, since it facilitates the growing of greenhouse vegetables during winter. Aeroponics, a technique in which plants are suspended and the roots misted with a nutrient solution, is another method for growing plants without soil.
The word “facilitates” in the passage is closest in meaning to
slows down
affects
makes easier
focuses on
According to paragraph 3, what is the advantage of hydroponics for research on nutrient deficiencies in plants?
it allows researchers to control what nutrients a plant receives
it allows researchers to observe the growth of a large number of plants simultaneously
it is possible to directly observe the roots of plants
it is unnecessary to keep misting plants with nutrient solutions
The word “suspended” in the passage is closest in meaning to
grown
protected
spread out
hung
PARAGRAPH 5
Scientists have known for some time that certain plants, called hyperaccumulators, can concentrate minerals at levels a hundredfold or greater than normal. A survey of known hyperaccumulators identified that 75 percent of them amassed nickel; cobalt, copper, zinc, manganese, lead, and cadmium are other minerals of choice. Hyperaccumulators run the entire range of the plant world. They may be herbs, shrubs, or trees. Many members of the mustard family, spurge family, legume family, and grass family are top hyperaccumulators. Many are found in tropical and subtropical areas of the world, where accumulation of high concentrations of metals may afford some protection against plant-eating insects and microbial pathogens.
8. Why does the author mention “herbs,” “shrubs,” and “trees”?
To provide examples of plant types that cannot tolerate high levels of harmful minerals
To show why so many plants are hyperaccumulators
To help explain why hyperaccumulators can be found in so many different places
To emphasize that hyperaccumulators occur in a wide range of plant types
9. The word “afford” in the passage is closest in meaning to
offer
prevent
increase
remove
PARAGRAPH 6
Only recently have investigators considered using these plants to clean up soil and waste sites that have been contaminated by toxic levels of heavy metals—an environmentally friendly approach known as phytoremediation. Toxic minerals would first be absorbed by roots but later relocated to the stem and leaves. A harvest of the shoots would remove the toxic compounds off site to be burned or composted to recover the metal for industrial uses. After several years of cultivation and harvest, the site would be restored at a cost much lower than the price of excavation and reburial, the standard practice for remediation of contaminated soils. For example, in field trials, the plant alpine pennycress removed zinc and cadmium from soils near a zinc smelter, and Indian mustard, native to Pakistan and India, has been effective in reducing levels of selenium salts by 50 percent in contaminated soils.
10. Which of the sentences below best expresses the essential information in the highlighted sentence in paragraph 6? Incorrect choices change the meaning in important ways or leave out essential information.
Before considering phytoremediation, hyperaccumulating species of plants local to the target area must be identified.
The investigation begins with an evaluation of toxic sites in the target area to determine the extent of contamination
The first step in phytoremediation is the planting of hyperaccumulating plants in the area to be cleaned up
Mines and irrigation ponds can be kept from becoming contaminated by planting hyperaccumulating species in targeted areas
11. It can be inferred from paragraph 6 that compared with standard practices for remediation of contaminated soils, phytoremediation
does not allow for the use of the removed minerals for industrial purposes
can be faster to implement
is equally friendly to the environment
is less suitable for soils that need to be used within a short period of time
12. Why does the author mention “Indian mustard”?
to warn about possible risks involved in phytoremediation
to help illustrate the potential pf phytoremediation
to show that hyper accumulating plants grow in many regions of the world
to explain how zinc contamination can be reduced
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Minerals and Plants
Research has shown that certain minerals are required by plants for normal growth and development The soil is the source of these minerals which are absorbed by the plant with the water from the soil Even nitrogen, which is a gas in its elemental state, is normally absorbed from the soil as nitrate ions Some soils are notoriously deficient in micro nutrients and are therefore unable to support most plant life So-called serpentine soils, for example, are deficient in calcium, and only plants able to tolerate low levels of this mineral can survive In modern agriculture, mineral depletion of soils is a major concern, since harvesting crops interrupts the recycling of nutrients back to the soil.
.
Introduction
Mineral deficiencies can often be detected by specific symptoms such as chlorosis {loss of chlorophyll resulting in yellow or white leaf tissue), necrosis (isolated dead patches), anthocyanin formation (development of deep red pigmentation of leaves or stem), stunted growth, and development of woody tissue in an herbaceous plant Soils are most commonly deficient in nitrogen and phosphorus. Nitrogen-deficient plants exhibit many of the symptoms just described Leaves develop chlorosis, stems are short and slender, and anthocyanin discoloration occurs on stems, petioles, and lower leaf surfaces Phosphorus-deficient plants are often stunted, with leaves turning a characteristic dark green, often with the accumulation of anthocyanin. Typically, older leaves are affected first as the phosphorus is mobilized to young growing tissue Iron deficiency is characterized by chlorosis between veins in young leaves.
Much of the research on nutrient deficiencies is based on growing plants hydroponically. that is. in soilless liquid nutrient solutions This technique allows researchers to create solutions that selectively omit certain nutrients and then observe the resulting effects on the plants Hydroponics has applications beyond basic research, since it facilitates the growing of greenhouse vegetables during winter. Aeroponics, a technique in which plants are suspended and the roots misted with a nutrient solution, is another method for growing plants without soil.
While mineral deficiencies can limit the growth of plants. an overabundance of certain minerals can be toxic and can also limit growth Saline soils, which have high concentrations of sodium chloride and other salts, limit plant growth, and research continues to focus on developing salt-tolerant varieties of agricultural crops Research has focused on the toxic effects of heavy metals such as lead, cadmium, mercury, and aluminum however, even copper and zinc, which are essential elements, can become toxic in high concentrations Although most plants cannot survive in these soils, certain plants have the ability to tolerate high levels of these minerals.
Scientists have known for some time that certain plants, called hyperaccumulators. can concentrate minerals at levels a hundredfold or greater than normal. A survey of known hyperaccumulators identified that 75 percent of them amassed nickel; cobalt, copper, zinc, manganese, lead, and cadmium are other minerals of choice.
Hyperaccumulators run the entire range of the plant world. They may be herbs shrubs, or trees. Many members of the mustard family, spurge family, legume family and grass family are top hyperaccumulators Many are found in tropical and subtropical areas of the world, where accumulation of high concentrations of metals may afford some protection against plant-eating insects and microbial pathogens.
Conclusion
Only recently have investigators considered using these plants to clean up soil and waste sites that have been contaminated by toxic levels of heavy metals – an environmentally friendly approach known as phytore mediation This scenario begins with the planting of hyperaccumulating species in the target area such as an abandoned mine or an irrigation pond contaminated by runoff Toxic minerals would first be absorbed by roots but later relocated to the stem and leaves A harvest of the shoots would remove the toxic compounds off site to be burned or composted to recover the metal for industrial uses After several years of cultivation and harvest, the site would be restored at a cost much lower than the price of excavation and reburial the standard practice for remediation of contaminated soils For example, in field trials, the plant alpine pennycress removed zinc and cadmium from soils near a zinc smelter, and Indian mustard, native to Pakistan and India has been effective in reducing levels of selenium salts by 50 percent in contaminated soils.
TOEFL Official Tests：Reading Test 2 Passage 1 “Minerals and Plants” の単語 ＜知っておくべき70語！＞
今回はOfficial Tests Volume 1 Test 2の最初のパッセージ “Minerals and Plants” の単語を紹介します。
（Official Tests Vol. 1、Reading Test 2のパッセージはTPO5と同じですが、中国TPOのサイトは問題のタイプミスがよくあるのでETS教材で問題を解くことをお勧めします。）
このパッセージでは以下のような専門用語が多く使われていますが、パッセージ中で説明されているものもいくつかあり、これらの専門性が高い表現を知らなくても全く問題ありません（また覚える必要もありません）。
serpentine soil「蛇紋岩（じゃもんがん）土壌」、chlorosis「[植物］ 白化」、anthocyanin「［化］ アントシアニン」、 hydroponics 「［農］水耕法、水栽培」、aeroponics「空中栽培」、chloride 「［化］ 塩化物」、phytoremediation「ファイトレメディエーション 《植物を利用して環境を修復・改善・浄化する技術》」、selenium salt「セレニウム塩」
今回はTOEFLを受けるなら知っていなければならない単語を70選んでいます。
（以前に取り上げたものもいくつか含まれています）
掲載した意味は文脈にそったものであり、皆さんが思いつく単語の意味とは異なっても気にしないでください。
TOEFLを受けるなら知っていなければならない基礎的な単語・表現：70語
mineral, soil, absorb, nitrogen, elemental, state, notoriously, deficient, nutrient, calcium, tolerate, depletion, concern, harvest, crop, interrupt, recycling, deficiency, detect, symptom, result in, tissue, isolated, patch, pigmentation, stem, woody, exhibit, characteristic, accumulation, mobilize, iron, vein, liquid, solution, selectively, application, facilitate, suspend, root, mist, toxic, concentration, tolerant, variety, agricultural, copper, identify, amass, entire, range, herb, shrub, tropical, subtropical, afford, investigator, waste, contaminate, scenario, abandoned, mine, irrigation, runoff, relocate, harvest, shoot, cultivation, restore, excavation
TOEFLで高得点を取るために知っておくべき単語・表現：17語
serpentine, chlorophyll, discoloration, overabundance, sodium, lead, mercury, aluminum, zinc, hundredfold, of choice, microbial, compound, compost, reburial, remediation, alpine
この問題に取り組み済みの人は覚えたい単語・表現：15語
necrosis, stunted, herbaceous, phosphorus, petiole, saline, cadmium, nickel, cobalt, manganese, legume, microbial, pathogen, off site, smelter
それぞれの単語の意味は下のリストにあります。
T mineral 鉱物；無機物、無機質、ミネラル 1 soil 土、土壌 1 absorb 〜を（徐々に）吸収する［吸い上げる、吸い込む］ 1 nitrogen [元素] 窒素 1 elemental [化] 元素の；要素の；基本的な、根本的な 1 state 状態、ありさま、様子 1 elemental state 元素状態 1 nitrate ion 硝酸イオン 1 notoriously 悪名高く（も）；周知のこととして = in a way that is famous for something bad 1 deficient （in 〜） （最低限必要なもの・ことが）不足した、欠けた、不十分な = lacking in some necessary quality or element 1 nutrient 栄養物、栄養になる食物、栄養素 1 micro nutrient 微量栄養素、微量養分 = micronutrient 1 serpentine （形や動きが）ヘビに似た、ヘビのような；蛇紋岩 = winding like a snake / full of bends and twists 1 serpentine soil 蛇紋岩（じゃもんがん）土壌 《主に蛇紋石（serpentine）からなる岩石。変成岩ないし火成岩中の超塩基性岩のどちらかに分類される。岩石の表面に蛇のような紋様が見られることから、蛇紋岩と命名された。》 1 calcium カルシウム 1 tolerate 〜に耐えられる［耐性がある］；～を我慢する；〜を許容する［大目に見る］ 1 depletion （資源などの）枯渇、減少、消耗 = when an amount of something is greatly reduced or nearly all used up 1 concern 関心事、懸案事項 = a worried or nervous feeling about something, or something that makes you feel worried 1 harvest （作物など）を収穫する、刈り入れる、取り入れる 1 crop （穀物・野菜・果物などの）作物、農作物、収穫物 1 interrupt ～を妨げる［邪魔する］；〜を中断する［遮断する］ 1 recycling 再生利用、リサイクリング 2 deficiency 不足、欠乏、欠如 2 detect ～を見つける［気づく、感知する］ 2 symptom 症状、症候、徴候；兆し、しるし 2 chlorosis [植物］ 白化 《植物の葉中のクロロフィル濃度が不足している状態。この状態の葉は黄色から白色になる。光合成とそれによる糖の合成を行う能力が失われている。「もやし」は故意に光を遮ってクロロフィルが生じないように育てたもの。》 2 chlorophyll クロロフィル、葉緑素 《植物の葉などに含まれる緑色色素で、細胞内の葉緑体にあり、太陽光を吸収してこれをエネルギー源として、水と空気中の二酸化炭素から糖などの有機物を合成する「光合成」を行なう。》 result in （結果的に）〜をもたらす、〜という結果になる、〜に終わる 2 tissue [生] （動植物の細胞の）組織；ティッシュペーパー 2 necrosis 壊死 《生体の一部の組織または細胞が死ぬこと》 = the localized death of living cells (as from infection or the interruption of blood supply 2 isolated 孤立した、分離した、隔離した、切り離された = happening only once, or existing only in one place 2 patch （色彩などが他と異なって見える）部分、斑点、まだら = a small area that is different in some way from the area that surrounds it 2 anthocyanin ［化］ アントシアニン = Any of various flavonoid glycoside pigments that impart red, purple, and blue colors to plant parts and are found in berries and other fruits, red wine, and certain vegetables 2 pigmentation ［生］ 色素沈着、色素形成；着色 = the natural coloring of animal or plant tissue 2 stem ［植物］ 茎 = the long thin central part of a plant from which the leaves and flowers grow 2 stunted 成長［発育］不良［不全］の = slowed or stopped abnormally in growth or development / prevented from growing or developing to the usual size 2 woody 木質の、木の（ような） herbaceous （木ではなく）草の、草本（そうほん）の 《草本：植物の地上に出ている部分が、軟らかで、木質になっていないものの総称。くさ。》 2 herbaceous plant 草本（性）植物、葉状植物 2 phosphorus [元素] リン = a nonmetallic element of the nitrogen family with atomic number 15 that occurs widely in combination especially as phosphates 「リン酸塩」, that is essential for life in all known organisms, and that is used especially in fertilizers and organophosphorus compounds 「有機リン化合物」 2 exhibit ～を見せる［表す、示す］ 2 slender か細い、細長い、ほっそりとした、すらっとした；薄弱な、不十分な 2 discoloration 変色（すること［していること］）、退色 2 petiole ［植物］葉柄（ようへい） 《葉身を茎や枝につないでいる細い柄の部分》 = leafstalk 2 characteristic 特徴的な、特有の、独特の 2 accumulation 蓄積、集積；蓄積物 2 mobilize ～を結集する［駆り集める］ = to marshal, bring together, prepare (power, force, wealth, etc.) for action, esp. of a vigorous nature 2 iron 鉄 2 vein ［植物］ 葉脈；静脈；（一般に）血管 3 nutrient deficiency 栄養不足、栄養素の欠乏 3 hydroponically ［農］ （栽培などが）水耕による、水耕法で、水耕栽培で 3 soilless 土壌を用いない、無土壌の 3 liquid 液体の、液状の 3 solution ［化］ 溶液 = a liquid with another substance dissolved in it, so that it has become part of the liquid 3 nutrient solution 栄養溶液 3 selectively 入念に選んで、選択的に、抜粋して = in a way that involves intentionally choosing some people or things and not others 3 omit ～を除く［入れない、含めない、除外する、省く］ 3 resulting 結果として生じる［起こる］ 3 hydroponics ［農］水耕法、水栽培 《単数扱い》 = tank farming 3 application 適用、応用、活用 = the practical purpose for which a machine, idea etc can be used, or a situation when this is used 3 facilitate ～を促進する［容易にする、楽にする、手助けする］ = to make it possible or easier for something to happen 3 greenhouse vegetable 温室野菜 3 aeroponics 空中栽培 《単数扱い》 3 suspend ～をつるす［（宙に）浮かせる、ぶら下げる］ 3 root （植物の）根、地下茎 3 mist （植物）に水を霧状にして吹き付ける［霧吹きで水をかける］ 4 limit 〜を制限する［限定する］ 4 overabundance 過多、過剰、多すぎ 4 toxic 有毒な、中毒（性）の；有害な、害を及ぼす 4 saline 塩分を含んだ、塩気のある；塩の 4 concentration ［化］ （溶液の）濃度；濃縮；集結 4 sodium ［化］ ナトリウム、ソディウム、ソジウム 4 chloride ［化］ 塩化物 4 sodium chloride ［化］ 塩化ナトリウム 4 tolerant 耐える、耐性がある、抵抗力がある；寛容な、寛大な 4 salt-tolerant 耐塩性の 4 variety ［生］ 亜種、異種；種、種類；多様性、変化 4 agricultural 農業の、農業で作られる 4 lead ［元素］ 鉛 4 cadmium ［元素］ カドミウム 4 mercury ［元素］ 水銀 4 aluminum ［元素］ アルミニウム 4 copper ［元素］ 銅 4 zinc ［元素］ 亜鉛 5 hyperaccumulator 超集積植物 = Any plant that can accumulate large quantities of trace elements from its environment and is often used in phytoremediation 5 concentrate （一か所に）～を集める［集結させる、集中させる］ 5 hundredfold 100倍に［の］ 5 survey 調査、検査 5 known 有名な、周知の、知られている 5 identify 〜を確認する［明らかにする、割り出す］：〜を特定する 5 amass ～を蓄える［蓄積する、（寄せ）集める］ = to get a large amount of something, especially money or information, by collecting it over a long period / gather together or accumulate (a large amount or number of valuable material or things) over a period of time 5 nickel ［元素］ ニッケル 5 cobalt ［元素］ コバルト 5 manganese ［元素］ マンガン 5 of choice 一般的に好まれる；えり抜きの、最適な = to be preferred / selected as one’s favorite or the best 5 run （範囲などが）及ぶ、広がる 5 entire 全部の、全体の、すべての；完全な 5 range 範囲、幅、領域 5 herb 草、草木；ハーブ、薬草 5 shrub 低木、灌木（かんぼく） 5 mustard ［植物］ カラシ、クロガラシ 5 family ［生物］ （生物分類の）科 5 spurge ［植物］ トウダイグサ 5 legume ［植物］ マメ科植物 5 tropical 熱帯（地方）の、熱帯性の 5 subtropical 亜熱帯（地方）の、亜熱帯性の 《温帯の中で、熱帯に接近した地帯。台湾など》 5 afford ～を提供する［利用可能にする、与える］ = to provide something or allow something to happen 5 microbial 微生物の、菌の 5 pathogen 病原体、病原菌 《病原となる、原生動物や細菌やウイルスなどの生物》 = something such as bacteria or a virus that causes disease 6 investigator 調査者、研究者；捜査員［官］ 6 clean up 〜を浄化する［片付ける、きれいに清掃する］ 6 waste 廃（棄）物 6 waste site 廃棄物処理場、投棄地 6 contaminate ～を汚染する［汚す、不純にする］ 6 heavy metal 重金属 6 phytoremediation ファイトレメディエーション 《植物を利用して環境を修復・改善・浄化する技術》 6 scenario 計画、筋書き、シナリオ 6 target area 目標地域、標的領域 6 abandoned 放棄された、今はもう使われていない；見捨てられた 6 mine 鉱山、採鉱場 6 irrigation 灌漑（かんがい） 《川・湖などから田畑に水を引くこと》 6 runoff （地中に吸収されるに流れる）雨水、排水、流出液 = a flow of water or chemicals from one place to another, especially when this damages the environment 6 relocate ～を（新しい場所に）移す［移動させる、移転させる］ 6 harvest （作物などの）収穫、取り入れ、収穫高 = the crops that have been gathered, or the amount and quality of the crops gathered 6 shoot 新芽、若枝 = the first part of a plant to appear above the ground as it develops from a seed, or any new growth on an already existing plant 6 compound ［化］化合物 6 toxic compound 毒性化合物 6 off site 現場から離れて、現地外で 6 compost ～を堆肥にする、〜から堆肥を作る 6 recover ～を回収する［取り出す］；〜を回復する［取り戻す］ 6 industrial use 産業利用、工業的用途 6 cultivation （作物の）栽培；（土地の）耕作 6 restore ～を元の状態に戻す、～を復元［復旧、修復］する 6 excavation 発掘（はっくつ）、採掘、掘削（くっさく） 6 reburial 埋め戻し、再び埋める行為、再埋葬 = the act or an instance of burying something for a second or subsequent time 6 standard practice 標準的技法、標準的な習慣 6 remediation （問題・欠点などの）改善、復旧、修復；治療 6 field trial 現場試行、実地試験、野外実験 6 alpine 高山（性）の；アルプス（山脈）の = relating to high mountains, especially the mountains of the European Alps 6 alpine pennycress ［植物］ アルパインペニークレス 《葉に大量の亜鉛、ニッケル、カドミウムを集積する性質がある。高濃度の金属を蓄積するのは病原微生物の侵入を防ぐためであることが分かった》 6 smelter 精錬所、溶鉱炉 6 Indian mustard ［植物］カラシナ 6 selenium salt セレニウム塩
以下では Official Tests Volume 1 Test 1の3パッセージの単語を確認できます。
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MINERALS AND PLANTS
MINERALS AND PLANTS
Research has shown that certain minerals are required by plants for normal growth and development. The soil is the source of these minerals, which are absorbed by the plant with the water from the soil. Even nitrogen, which is a gas in its elemental state, in normally absorbed from the soil as nitrate ions. Some soils are notoriously deficient in micro nutrients and are therefore unable to support most plant life. So-called serpentine soils, for example, are deficient in calcium, and only plants able to tolerate low levels of this mineral can survive. In modern agriculture, mineral depletion of soils is a major concern, since harvesting crops interrupts the recycling of nutrients back to the soil.
Mineral deficiencies can often be detected by specific symptoms such as chlorosis (loss of chlorophyll resulting in yellow or white leaf issue), necrosis (isolated dead patches), anthocyanin formation (development of deep red pigmentation of leaves or stem), stunted growth, and development of woody tissue in an herbaceous plant. Soils are most commonly deficient in nitrogen and phosphorus. Nitrogen-deficient plants exhibit many of the symptoms just described. Leaves develop chlorosis; stems are short and slender, and anthocyanin discoloration occurs on stems, petioles, and lower leaf surfaces. Phosphorus-deficient plants are often stunted, with leaves turning a characteristic dark green, often with the accumulation of anthocyanin. Typically, older leaves are affected first as the phosphorus is mobilized to young growing tissue. Iron deficiency is characterized by chlorosis between veins in young leaves.
Much of the research on nutrient deficiencies is based on growing plants hydroponically, that is, in soilless liquid nutrient solutions. This technique allows researchers to create solutions that selectively omit certain nutrients and then observe the resulting effects on the plants. Hydroponics has applications beyond basic research, since it facilitates the growing of greenhouse vegetables during winter. Acroponics, a technique in which plants are suspended and the roots misted with a nutrient solution, is another method for growing plants without soil.
While mineral deficiencies can limit the growth of plants, an overabundance of certain minerals can be toxic and can also limit growth. Saline soils, which have high concentrations of sodium chloride and other salts, limit plant growth, and research continues to focus on developing salt-tolerant varieties of agricultural crops. Research has focused on the toxic effects of heavy metals such as lead, cadmium, mercury, and aluminum; however, even copper and zinc, which are essential elements, can become toxic in high concentrations. Although most plants cannot survive in these soils, certain plants have the ability to tolerate high levels of these minerals.
Scientists have known for some time that certain plants, called hyper accumulators, can concentrate minerals at levels a hundredfold or greater than normal. A survey of known hyper accumulators identified that 75 percent of them amassed nickel, cobalt, copper, zinc, manganese, lead, and cadmium are other minerals of choice. Hyper accumulators run the entire range of the plant world. They may be herbs, shrubs, or trees. Many members of the mustard family, spurge family, legume family, and grass family are top hyper accumulators. Many are found in tropical and subtropical areas of the world, where accumulation of high concentrations of metals may afford some protection against plant-eating insects and microbial pathogens.
Only recently have investigators considered using these plants to clean up soil and waste sites that have been contaminated by toxic levels of heavy metals – an environmentally friendly approach known as phytoremediation. This scenario begins with the planting of hyper accumulating species in the target area, such as an abandoned mine or an irrigation pond contaminated by runoff. Toxic minerals would first be absorbed by roots but later relocated to the stem and leaves. A harvest of the shoots would remove the toxic compounds off site to be burned or composted to recover the metal for industrial uses. After several years of cultivation and harvest, the site would be restored at a cost much lower than the price of excavation and reburial, the standard practice for remediation of contaminated soils. For examples, in field trials, the plant alpine pennycress removed zinc and cadmium from soils near a zinc smelter, and Indian mustard, native to Pakistan and India, has been effective in reducing levels of selenium salts by 50 percent in contaminated soils.
Paragraph1: Research has shown that certain minerals are required by plants for normal growth and development. The soil is the source of these minerals, which are absorbed by the plant with the water from the soil. Even nitrogen, which is a gas in its elemental state, in normally absorbed from the soil as nitrate ions. Some soils are notoriously[in a way that is famous for something bad:] deficient[not having enough of:] in micro nutrients and are therefore unable to support most plant life. So-called serpentine soils, for example, are deficient in calcium, and only plants able to tolerate low levels of this mineral can survive. In modern agriculture, mineral depletion of soils is a major concern, since harvesting crops interrupts the recycling of nutrients back to the soil.
1. According to Paragraph1, what is true of plants that can grow in serpentine soil?2
¡ They absorb micronutrients unusually well.[no]
¡ They require far less calcium than most plants do.[yes]
¡ They are able to absorb nitrogen in its elemental state.[but lack of certain element]
¡ They are typically crops raised for food.[no,not mentioned]
Paragraph2: Mineral deficiencies can often be detected[to notice something that is partly hidden or not clear, or to discover something, especially using a special method] by specific symptoms such as chlorosis (loss of chlorophyll[the green substance in plants, that allows them to use the energy from the sun] resulting in yellow or white leaf issue), necrosis (isolated dead patches[a small area that is different in some way from the area that surrounds it:]), anthocyanin formation (development of deep red pigmentation[the natural colour of something, usually a living thing] of leaves or stem), stunted[prevented from growing or developing to the usual size:] growth, and development of woody tissue in an herbaceous[(of plants) soft and not woody] plant. Soils are most commonly deficient in nitrogen and phosphorus. Nitrogen-deficient plants exhibit many of the symptoms just described. Leaves develop chlorosis; stems are short and slender[ thin and delicate, often in a way that is attractive:], and anthocyanin discoloration occurs on stems, petioles[], and lower leaf surfaces. Phosphorus-deficient plants are often stunted, with leaves turning a characteristic dark green, often with the accumulation of anthocyanin. Typically, older leaves are affected first as the phosphorus is mobilized to young growing tissue. Iron deficiency is characterized by chlorosis between veins[a tube that carries blood to the heart from the other parts of the body] in young leaves.
[deficiency can be seen,n: ;p:older;i:young]2. The word exhibit in the passage is closest in meaning to2
¡ fight off
¡ show
¡ cause
¡ spread
3. According to Paragraph2, which of the following symptoms occurs in phosphorus-deficient plants but not in plants deficient in nitrogen or iron?2
¡ Chlorosis on leaves[n]
¡ Change in leaf pigmentation to a dark shade of green[p]
¡ Short, stunted appearance of stems[n]
¡ Reddish pigmentation on the leaves or stem[n]
4. According to Paragraph2, a symptom of iron deficiency is the presence in young leaves of2
¡ Deep red discoloration between the veins.
¡ White or yellow tissue between the veins.
¡ Dead spots between the veins.
¡ Characteristic dark green veins.
Paragraph3: Much of the research on nutrient deficiencies is based on growing plants hydroponically[he method of growing plants in water to which special chemicals are added, rather than growing them in earth], that is, in soilless liquid nutrient solutions. This technique allows researchers to create solutions that selectively omit certain nutrients and then observe the resulting effects on the plants. Hydroponics has applications beyond basic research, since it facilitates the growing of greenhouse vegetables during winter. Acroponics, a technique in which plants are suspended and the roots misted[a light rain or a collection of very small drops of water in the air that is like a fog:] with a nutrient solution, is another method for growing plants without soil.
[hydroponically:experiment technology vs acroponics:suspend]5. The word facilitates in the passage is closest in meaning to3
¡ slows down
¡ affects
¡ makes easier
¡ focuses on
6. According to Paragraph3, what is the advantage of hydroponics for research on nutrient deficiencies in plants?1
Translate “This technique allows researchers to create solutions that selectively omit certain nutrients and then observe the resulting effects on the plants.”
¡ It allows researchers to control what nutrients a plant receives.[yes]
¡ It allows researchers to observe the growth of a large number of plants simultaneously.[no]
¡ It is possible to directly observe the roots of plants.[parts]
¡ It is unnecessary to keep misting plants with nutrient solutions.[mix another technology]
7. The word suspended in the passage is closest in meaning to4
¡ grown
¡ protected
¡ spread out
¡ hung
Paragraph5: Scientists have known for some time that certain plants, called hyper[having too much of a quality:] accumulators, can concentrate minerals at levels a hundredfold or greater than normal. A survey of known hyper accumulators identified that 75 percent of them amassed[to get a large amount of something, especially money or information, by collecting it over a long period:] nickel, cobalt, copper, zinc, manganese, lead, and cadmium are other minerals of choice. Hyper accumulators run the entire range of the plant world. They may be herbs , shrubs , or trees . Many members of the mustard[a thick yellow or brown sauce that tastes spicy and is eaten cold in small amounts, especially with meat] family, spurge family, legume[a plant that has its seeds in a pod, such as the bean or pea] family, and grass family are top hyper accumulators. Many are found in tropical and subtropical areas of the world, where accumulation of high concentrations of metals may afford some protection against plant-eating insects and microbial pathogens.
[Hyper accumulators:various minerals and kinds of plants.]8. Why does the author mention herbs , shrubs , and trees ?[Hyper accumulators run the entire range of the plant world.]4
¡ To provide examples of plant types that cannot tolerate high levels of harmful minerals.[no]
¡ To show why so many plants are hyper accumulators.[no]
¡ To help explain why hyper accumulators can be found in so many different places.[no,not to explain]
¡ To emphasize that hyper accumulators occur in a wide range of plant types.[yes]
9. The word afford in the passage is closest in meaning to1
¡ offer
¡ prevent
¡ increase
¡ remove
Paragraph 6: Only recently have investigators considered using these plants to clean up soil and waste sites that have been contaminated by toxic levels of heavy metals – an environmentally friendly approach known as phytoremediation. This scenario[ a description of possible actions or events in the future: ] begins with the planting of hyper accumulating species in the target area, such as an abandoned[ left in a particular place or condition, usually forever: ] mine or an irrigation pond contaminated by runoff. Toxic minerals would first be absorbed by roots but later relocated to the stem and leaves. A harvest[the time of year when crops are cut and collected from the fields, or the activity of cutting and collecting them, or the crops that are cut and collected:] of the shoots[the first part of a plant to appear above the ground as it develops from a seed, or any new growth on an already existing plant:] would remove the toxic compounds off site to be burned or composted to recover the metal for industrial uses. After several years of cultivation and harvest, the site would be restored at a cost much lower than the price of excavation[the act of removing earth that is covering very old objects buried in the ground in order to discover things about the past:] and reburial[the act of putting a dead body into the ground, or the ceremony connected with this:], the standard practice for remediation[the process of improving or correcting a situation:] of contaminated soils. For examples, in field trials, the plant alpine pennycress removed zinc and cadmium from soils near a zinc smelter, and Indian mustard , native to Pakistan and India, has been effective in reducing levels of selenium salts by 50 percent in contaminated soils.
[use plant to clean up the soil,planting,absorbing,relocate,cheaper]10. Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information.3
¡ Before considering phytoremediation, hyper accumulating species of plants local to the target area must be identified.[no,not to identify]
¡ The investigation begins with an evaluation of toxic sites in the target area to determine the extent of contamination.[no,not make evaluation]
¡ The first step in phytoremediation is the planting of hyper accumulating plants in the area to be cleaned up.[yes]
¡ Mines and irrigation ponds can be kept from becoming contaminated by planting hyper accumulating species in targeted areas.[no,lack of mines]
11. It can be inferred from Paragraph6 that compared with standard practices for remediation of contaminated soils, phytoremediation4
¡ does not allow for the use of the removed minerals for industrial purposes.
¡ can be faster to implement[no,not mentioned the fast]
¡ is equally friendly to the environment[yes,but not used to be compared]
¡ is less suitable for soils that need to be used within a short period of time.[refer to “After several years of cultivation and harvest,”]
12. Why does the author mention Indian mustard ?2
¡ To warn about possible risks involved in phytoremediation[no,not risk]
¡ To help illustrate the potential of phytoremediation[yes]
¡ To show that hyper accumulating plants grow in many regions of the world[no]
¡ To explain how zinc contamination can be reduced.[no,not to explain]
Paragraph5: Scientists have known for some time that certain plants, called hyper accumulators, can concentrate minerals at levels a hundredfold or greater than normal. ■ A survey of known hyper accumulators identified that 75 percent of them amassed nickel, cobalt, copper, zinc, manganese, lead, and cadmium are other minerals of choice. ■Hyper accumulators run the entire range of the plant world. ■ They may be herbs, shrubs, or trees. ■ Many members of the mustard family, spurge family, legume family, and grass family are top hyper accumulators. Many are found in tropical and subtropical areas of the world, where accumulation of high concentrations of metals may afford some protection against plant-eating insects and microbial pathogens.
13. Look at the four squares [■] that indicate where the following sentence could be added to the passage.
Certain minerals are more likely to be accumulated in large quantities than others.[examples later]
Where could the sentence best fit?1
14. Directions: An introductory sentence for a brief summary of the passage is provided below. Complete the summary by selecting the THREE answer choices that express the most important ideas in the passage. Some answer choices do not belong in the summary because they express ideas that are not presented in the passage or are minor ideas in the passage. This question is worth 2 points.
Plants need to absorb certain minerals from the soil in adequate quantities for normal growth and development.
●1
●2
●3
Answer Choices
1. Some plants are able to accumulate extremely high levels of certain minerals and thus can be used to clean up soils contaminated with toxic levels of these minerals.[yes]
2. Though beneficial in lower levels, high levels of salts, other minerals, and heavy metals can be harmful to plants.[yes]
3. When plants do not absorb sufficient amounts of essential minerals, characteristic abnormalities result.[yes]
4. Because high concentrations of sodium chloride and other salts limit growth in most plants, much research has been done in an effort to develop salt-tolerant agricultural crops.[no,they develop the mine-tolerant plants]
5. Some plants can tolerate comparatively low levels of certain minerals, but such plants are of little use for recycling nutrients back into depleted soils.[no,not mention the low level]
6. Mineral deficiencies in many plants can be cured by misting their roots with a nutrient solution or by transferring the plants to a soilless nutrient solution.[a method to solve the soilless problem]
参考答案：
1.○2
2.○2
3.○2
4.○2
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矿物质和植物
研究表明，某些矿物质是植物正常生长发育所必需的。土壤是这些矿物质的来源，它们通过水分被植物从土壤中吸收。即使是元素状态为气体的氮，也通常作为硝酸根离子从土壤中被吸收。众所周知，一些土壤缺乏微量营养素，因此大多数植物不能生长。例如所谓的蛇纹岩土壤，由于缺乏钙，只有那些能忍受如此低水平的钙的植物才能够存活。在现代农业，土壤矿物质枯竭是一个大问题，因为收割庄稼切断了养分返回土壤的循环。
矿物质缺乏通常可由特定的症状检测出来，如褪绿（叶绿素损失导致黄叶或白叶的现象）、坏疽（孤立的坏死斑）、花青素的形成（形成深红色叶片和茎色素沉积）、发育不良，以及草本植物长木质组织。土壤最常缺乏的是氮和磷。氮缺乏植物表现出了刚才描述的许多症状：叶片黄化、茎短而细以及发生在茎、叶柄以及叶子下角质层的花青素变色。磷缺乏的植物往往发育不良，叶片变成特殊的深绿色，经常伴随着花青素的积累。由于磷流向新生的组织，通常较老的叶片首先受到影响。铁缺乏症的特点是嫩叶的叶脉之间萎黄。
大多数关于营养素缺乏症的研究都基于水培法，即在无土营养液中培养。这项技术允许研究人员创造缺乏某种营养素的溶液，然后观察对植物生长造成的影响。水培法的应用已经超越了基础研究，因为它促进了温室蔬菜在冬季的生长。气培法，一种把植物悬挂起来，将其根部浸入营养液，是另外一种无土栽培的方法。
虽然缺乏矿物质会抑制植物生长，但某些矿物质过量可能会有毒，同样也会抑制植物生长。含有高浓度的氯化钠和其他盐类的盐碱土壤抑制植物生长，于是研究继续集中开发耐盐农作物品种。着重研究重金属的毒性作用，如铅、镉、汞、铝；然而即使是铜和锌这样的必需元素，如果浓度过高也会产生毒性。虽然大多数植物无法在这种土壤生存，某些植物却能够忍耐如此高含量的矿物质。
科学家早前就了解到，某些所谓的富集植物能够比普通植物多集中一百倍甚至更多的矿物质。一项对已知富集植物的调查表明，它们中75%积聚了镍，而钴、铜、锌、锰、铅和镉则是其他选择性聚集的矿物质。富集植物广泛分布于整个植物界，它们可能是草本植物、灌木或树。芥属、大戟属、豆科和禾本科植物中的许多成员都是靠前的富集植物。许多富集植物被发现于热带和亚热带，金属可以为植物提供保护，对抗食草类昆虫和细菌病原体。
直到最近研究者才考虑用这些植物来清理已经被有毒重金属污染的土壤和废弃物物处理点——一种被称为植物修复的环境友好方法。这套方案首先从在目标区域种植超积累物种开始，如在废弃矿井和被径流污染的灌溉池塘。有毒矿物质首先被根吸收，随后被运送至茎和叶。收割下来的枝叶将被焚烧以移除有毒化合物或被制成混合肥料回收金属用于工业。经过几年的种植和收割，该污染点将被修复，而其造价远比修复污染土壤的标准做法——挖掘和填埋来得低。举例来说，在实地试验中，高山菥蓂从靠近一个锌冶炼厂的土壤中去除了锌和镉，原产自巴基斯坦和印度的印度芥菜可以将染土壤中硒的水平有效地降低50%。
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