1.
Seed
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A seed is an embryonic plant enclosed in a protective outer covering. The formation of the seed is part of the process of reproduction in seed plants, Seeds are the product of the ripened ovule, after fertilization by pollen and some growth within the mother plant. The embryo is developed from the zygote and the coat from the integuments of the ovule. Seed plants now dominate biological niches on land, from forests to both in hot and cold climates. The term seed also has a meaning that antedates the above—anything that can be sown, e. g. seed potatoes. In the case of sunflower and corn seeds, what is sown is the seed enclosed in a shell or husk, many structures commonly referred to as seeds are actually dry fruits. Plants producing berries are called baccate, sunflower seeds are sometimes sold commercially while still enclosed within the hard wall of the fruit, which must be split open to reach the seed. Different groups of plants have other modifications, the stone fruits have a hardened fruit layer fused to. Nuts are the one-seeded, hard-shelled fruit of plants with an indehiscent seed. Seeds are produced in several related groups of plants, and their manner of production distinguishes the angiosperms from the gymnosperms, angiosperm seeds are produced in a hard or fleshy structure called a fruit that encloses the seeds, hence the name. Some fruits have layers of hard and fleshy material. In gymnosperms, no special structure develops to enclose the seeds, however, the seeds do become covered by the cone scales as they develop in some species of conifer. Seed production in natural plant populations varies widely from year-to-year in response to weather variables, insects and diseases, over a 20-year period, for example, forests composed of loblolly pine and shortleaf pine produced from 0 to nearly 5 million sound pine seeds per hectare. Over this period, there were six bumper, five poor, and nine good seed crops, right after fertilization, the zygote is mostly inactive, but the primary endosperm divides rapidly to form the endosperm tissue. This tissue becomes the food the young plant will consume until the roots have developed after germination, after fertilization the ovules develop into the seeds. The ovule consists of a number of components, The funicle or seed stalk which attaches the ovule to the placenta and hence ovary or fruit wall, the nucellus, the remnant of the megasporangium and main region of the ovule where the megagametophyte develops. The micropyle, a pore or opening in the apex of the integument of the ovule where the pollen tube usually enters during the process of fertilization. The chalaza, the base of the ovule opposite the micropyle, the shape of the ovules as they develop often affects the final shape of the seeds
2.
Tuber
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Tubers are enlarged structures in some plant species used as storage organs for nutrients. They are used for the plants perennation, to energy and nutrients for regrowth during the next growing season. Stem tubers form from thickened rhizomes or stolons, common plant species with stem tubers include potato and yam. Some sources also treat modified lateral roots under the definition, these are encountered in sweet potato, cassava, the term originates from Latin tuber, meaning lump, bump, swelling. Some sources define the term tuber to mean only structures derived from stems, a stem tuber forms from thickened rhizomes or stolons. The top sides of the tuber produce shoots that grow into stems and leaves. They tend to form at the sides of the parent plant and are most often located near the soil surface, the underground stem tuber is normally a short-lived storage and regenerative organ developing from a shoot that branches off a mature plant. The offsprings or new tubers are attached to a parent tuber or form at the end of a hypogeogenous rhizome, some plants also form smaller tubers and/or tubercules which act like seeds, producing small plants that resemble seedlings. Stem tubers generally start off as enlargements of the section of a seedling. Tuberous begonia, yams, and Cyclamen are commonly grown stem tubers, mignonette vine produces aerial stem tubers on 12-to-25-foot-tall vines, the tubers fall to the ground and grow. Enlarged stolons thicken to develop into storage organs, the tuber has all the parts of a normal stem, including nodes and internodes. The nodes are the eyes and each has a leaf scar, the nodes or eyes are arranged around the tuber in a spiral fashion beginning on the end opposite the attachment point to the stolon. The terminal bud is produced at the farthest point away from the stolon attachment, internally, a tuber is filled with starch stored in enlarged parenchyma like cells. The inside of a tuber has the cell structures of any stem, including a pith, vascular zones. The tuber is produced in one growing season and used to perennate the plant, as the main shoot develops from the tuber, the base of the shoot close to the tuber produces adventitious roots and lateral buds on the shoot. The shoot also produces stolons that are long etiolated stems, the stolon elongates during long days with the presence of high auxins levels that prevent root growth off of the stolon. Before new tuber formation begins, the stolon must be a certain age, the enzyme lipoxygenase makes a hormone, jasmonic acid, which is involved in the control of potato tuber development. The stolons are easily recognized when potato plants are grown from seeds, as the plants grow, stolons are produced around the soil surface from the nodes
3.
Phaseolus vulgaris
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Phaseolus vulgaris, the common bean, is a herbaceous annual plant grown worldwide for its edible dry seed or unripe fruit. Raw or undercooked beans contain the toxin phytohaemagglutinin and its leaf is also occasionally used as a vegetable and the straw as fodder. The common bean is a variable species that has a long history of cultivation. All wild members of the species have a habit, but many cultivars are classified as bush beans or pole beans. These include the bean, the navy bean, the pinto bean. The other major types of commercially grown bean are the runner bean, Beans are grown in every continent except Antarctica. Brazil and India are the largest producers of dry beans, while China produces, by far, worldwide,23 million tonnes of dry common beans and 17.1 million tonnes of green beans were grown in 2010. Along with squash and maize, beans are one of the Three Sisters central to indigenous North American agriculture, the common bean is a highly variable species with a long history. Bush varieties form erect bushes 20–60 cm tall, while pole or running varieties form vines 2–3 m long, all varieties bear alternate, green or purple leaves, which are divided into three oval, smooth-edged leaflets, each 6–15 cm long and 3–11 cm wide. The white, pink, or purple flowers are about 1 cm long and these may be green, yellow, black, or purple in color, each containing 4–6 beans. The beans are smooth, plump, kidney-shaped, up to 1.5 cm long, range widely in color, and are often mottled in two or more colors. Similar to other beans, the bean is high in starch, protein, and dietary fiber, and is an excellent source of iron, potassium, selenium, molybdenum, thiamine, vitamin B6. Dry beans will keep indefinitely if stored in a cool, dry place, dried beans are almost always cooked by boiling, often after being soaked in water for several hours. While the soaking is not strictly necessary, it shortens cooking time, in addition, soaking beans removes 5 to 10% of the gas-producing sugars that can cause flatulence for some people. The methods include simple overnight soaking and the power soak method in which beans are boiled for three minutes and then set aside for 2–4 hours, before cooking, the soaking water is drained off and discarded. Dry common beans take longer to cook than most pulses, cooking times vary from one to four hours, in Mexico, Central America, and South America, the traditional spice used with beans is epazote, which is also said to aid digestion. In East Asia, a type of seaweed, kombu, is added to beans as they cook for the same purpose, salt, sugar, and acidic foods such as tomatoes may harden uncooked beans, resulting in seasoned beans at the expense of slightly longer cooking times. Dry beans may also be cooked and canned as refried beans, or whole with water, salt
4.
Ricinus
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Ricinus communis, the castorbean or castor-oil-plant, is a species of perennial flowering plant in the spurge family, Euphorbiaceae. It is the species in the monotypic genus, Ricinus. The evolution of castor and its relation to other species are currently being studied using modern genetic tools and it reproduces with a mixed pollination system which favors selfing by geitonogamy but at the same time can be an out-crosser by anemophily or entomophily. Its seed is the bean, which, despite its name, is not a true bean. Castor is indigenous to the southeastern Mediterranean Basin, Eastern Africa, and India, castor seed is the source of castor oil, which has a wide variety of uses. The seeds contain between 40% and 60% oil that is rich in triglycerides, mainly ricinolein, the seed also contains ricin, a water-soluble toxin, which is also present in lower concentrations throughout the plant. An unrelated plant species, Fatsia japonica, is similar in appearance, Ricinus communis can vary greatly in its growth habit and appearance. The variability has been increased by breeders who have selected a range of cultivars for leaf and flower colours and it is a fast-growing, suckering shrub that can reach the size of a small tree, but it is not cold hardy. The glossy leaves are 15–45 centimetres long, long-stalked, alternate and palmate with 5–12 deep lobes with toothed segments. In some varieties they start off dark purple or bronze when young, gradually changing to a dark green, sometimes with a reddish tinge. Plants with the leaves can be found growing next to those with green leaves. The stems also vary in pigmentation, the fruit capsules of some varieties are more showy than the flowers. The flowers are borne in terminal inflorescences of green or, in some varieties, shades of red. The fruit is a spiny, greenish capsule containing large, oval, shiny, bean-like, castor seeds have a warty appendage called the caruncle, which is a type of elaiosome. The caruncle promotes the dispersal of the seed by ants, the name Ricinus is a Latin word for tick, the seed is so named because it has markings and a bump at the end that resemble certain ticks. The common name castor oil probably comes from its use as a replacement for castoreum and it has another common name, palm of Christ, or Palma Christi, that derives from castor oils reputed ability to heal wounds and cure ailments. Castor oil has many uses in medicine and other applications, an alcoholic extract of the leaf was shown, in lab rats, to protect the liver from damage from certain poisons. Methanolic extracts of the leaves of Ricinus communis were used in testing against eight pathogenic bacteria in rats
5.
Wheat
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Wheat is a cereal grain, originally from the Levant region but now cultivated worldwide. In 2016, world production of wheat was 749 million tonnes, making it the second most-produced cereal after maize, since 1960, world production of wheat and other grain crops has tripled and is expected to grow further through the middle of the 21st Century. This grain is grown on land area than any other commercial food. World trade in wheat is greater than for all other crops combined, globally, wheat is the leading source of vegetal protein in human food, having a protein content of about 13%, which is relatively high compared to other major cereals and staple foods. The archaeological record suggests that wheat was first cultivated in the regions of the Fertile Crescent around 9600 BCE. In a small part of the population, gluten – the major part of wheat protein – can trigger coeliac disease, non-coeliac gluten sensitivity, gluten ataxia. Cultivation and repeated harvesting and sowing of the grains of wild grasses led to the creation of domestic strains, in domesticated wheat, grains are larger, and the seeds remain attached to the ear by a toughened rachis during harvesting. In wild strains, a more fragile rachis allows the ear to easily shatter, as the traits that improve wheat as a food source also involve the loss of the plants natural seed dispersal mechanisms, highly domesticated strains of wheat cannot survive in the wild. Cultivation of wheat began to spread beyond the Fertile Crescent after about 8000 BCE, jared Diamond traces the spread of cultivated emmer wheat starting in the Fertile Crescent sometime before 8800 BCE. Archaeological analysis of wild emmer indicates that it was first cultivated in the southern Levant with finds dating back as far as 9600 BCE, Genetic analysis of wild einkorn wheat suggests that it was first grown in the Karacadag Mountains in southeastern Turkey. Dated archeological remains of wheat in settlement sites near this region, including those at Abu Hureyra in Syria. With the anomalous exception of two grains from Iraq ed-Dubb, the earliest carbon-14 date for einkorn wheat remains at Abu Hureyra is 7800 to 7500 years BCE. Remains of harvested emmer from several sites near the Karacadag Range have been dated to between 8600 and 8400 BCE, that is, in the Neolithic period and these remains were dated by Willem van Zeist and his assistant Johanna Bakker-Heeres to 8800 BCE. They also concluded that the settlers of Tell Aswad did not develop this form of emmer themselves, the cultivation of emmer reached Greece, Cyprus and India by 6500 BCE, Egypt shortly after 6000 BCE, and Germany and Spain by 5000 BCE. The early Egyptians were developers of bread and the use of the oven, by 3000 BCE, wheat had reached the British Isles and Scandinavia. A millennium later it reached China, the oldest evidence for hexaploid wheat has been confirmed through DNA analysis of wheat seeds, dating to around 6400-6200 BCE, recovered from Çatalhöyük. The first identifiable bread wheat with sufficient gluten for yeasted breads has been identified using DNA analysis in samples from a dating to approximately 1350 BCE at Assiros in Macedonia. From Asia, wheat continued to spread throughout Europe, in the British Isles, wheat straw was used for roofing in the Bronze Age, and was in common use until the late 19th century
6.
Rye
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Rye is a grass grown extensively as a grain, a cover crop and a forage crop. It is a member of the tribe and is closely related to barley. Rye grain is used for flour, rye bread, rye beer, crisp bread, some whiskeys, some vodkas and it can also be eaten whole, either as boiled rye berries or by being rolled, similar to rolled oats. Rye is a grain and should not be confused with ryegrass, which is used for lawns, pasture. Rye is one of a number of species grow wild in central and eastern Turkey. It is possible that rye traveled west from Turkey as an admixture in wheat. Since the Middle Ages people have cultivated rye widely in Central and it serves as the main bread cereal in most areas east of the French-German border and north of Hungary. In Southern Europe, it was cultivated on marginal lands, claims of much earlier cultivation of rye, at the Epipalaeolithic site of Tell Abu Hureyra in the Euphrates valley of northern Syria remain controversial. Critics point to inconsistencies in the dates, and identifications based solely on grain. Winter rye is any breed of rye planted in the fall to provide cover for the winter. It grows during warmer days of the winter when sunlight temporarily warms the plant above freezing and it is sometimes used in winter gardens and is a common nurse crop. Rye is grown primarily in Eastern, Central and Northern Europe, the main rye belt stretches from northern Germany through Poland, Ukraine, Belarus, Lithuania and Latvia into central and northern Russia. Rye is also grown in North America, in South America, in Oceania, in Turkey, in Kazakhstan, production levels of rye have fallen in most of the producing nations, as of 2012. For instance, production of rye in Russia fell from 13.9 million metric tons in 1992 to 2.1 t in 2012, most rye is consumed locally or exported only to neighboring countries, rather than being shipped worldwide. Rye is highly susceptible to the ergot fungus, consumption of ergot-infected rye by humans and animals results in a serious medical condition known as ergotism. Ergotism can cause physical and mental harm, including convulsions, miscarriage, necrosis of digits, hallucinations. Historically, damp northern countries that have depended on rye as a staple crop were subject to epidemics of this condition. There have been occurrence of ergotism with periods where there were incidents of people persecuted for being witches
7.
Oat
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The oat, sometimes called the common oat, is a species of cereal grain grown for its seed, which is known by the same name. While oats are suitable for consumption as oatmeal and rolled oats. The wild ancestor of Avena sativa and the related minor crop. Genetic evidence shows the forms of A. sterilis grew in the Fertile Crescent of the Near East. Domesticated oats appear relatively late, and far from the Near East, oats, like rye, are usually considered a secondary crop, i. e. derived from a weed of the primary cereal domesticates wheat and barley. As these cereals spread westwards into cooler, wetter areas, this may have favored the oat weed component, oats are best grown in temperate regions. Oats are a plant, and can be planted either in autumn or in the spring. Oats have numerous uses in foods, most commonly, they are rolled or crushed into oatmeal, oatmeal is chiefly eaten as porridge, but may also be used in a variety of baked goods, such as oatcakes, oatmeal cookies and oat bread. Oats are also an ingredient in many cold cereals, in particular muesli, historical attitudes towards oats have varied. Oat bread was first manufactured in Britain, where the first oat bread factory was established in 1899, in Scotland, they were, and still are, held in high esteem, as a mainstay of the national diet. In Scotland, a dish was made by soaking the husks from oats for a week, so the fine, floury part of the meal remained as sediment to be strained off, boiled and eaten. Oats are also used there as a thickener in soups. Oats are also used as feed for horses when extra carbohydrates. The oat hull may be crushed for the horse to easily digest the grain. They may be given alone or as part of a food pellet. Cattle are also fed oats, either whole or ground into a coarse flour using a mill, burr mill. Winter oats may be grown as a groundcover and ploughed under in the spring as a green fertilizer. They also can be used for pasture, they can be grazed a while, then allowed to head out for grain production, Oat straw is prized by cattle and horse producers as bedding, due to its soft, relatively dust-free, and absorbent nature
8.
Rice
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Rice is the seed of the grass species Oryza sativa or Oryza glaberrima. As a cereal grain, it is the most widely consumed staple food for a part of the worlds human population. It is the agricultural commodity with the third-highest worldwide production, after sugarcane and maize, wild rice, from which the crop was developed, may have its native range in Australia. Chinese legends attribute the domestication of rice to Shennong, the emperor of China. Genetic evidence has shown that rice originates from a single domestication 8, previously, archaeological evidence had suggested that rice was domesticated in the Yangtze River valley region in China. From East Asia, rice was spread to Southeast and South Asia, Rice was introduced to Europe through Western Asia, and to the Americas through European colonization. There are many varieties of rice and culinary preferences tend to vary regionally, in some areas such as the Far East or Spain, there is a preference for softer and stickier varieties. Rice, a monocot, is grown as an annual plant, although in tropical areas it can survive as a perennial. The rice plant can grow to 1–1.8 m tall, occasionally more depending on the variety and it has long, slender leaves 50–100 cm long and 2–2.5 cm broad. The small wind-pollinated flowers are produced in a branched arching to pendulous inflorescence 30–50 cm long, the edible seed is a grain 5–12 mm long and 2–3 mm thick. Rice cultivation is well-suited to countries and regions with low costs and high rainfall, as it is labor-intensive to cultivate. However, rice can be grown practically anywhere, even on a hill or mountain area with the use of water-controlling terrace systems. Although its parent species are native to Asia and certain parts of Africa, centuries of trade, the traditional method for cultivating rice is flooding the fields while, or after, setting the young seedlings. The name wild rice is used for species of the genera Zizania and Porteresia. The Greek word is the source of all European words, the origin of the Greek word is unclear. It is sometimes held to be from the Tamil word அரிசி, however, Krishnamurti disagrees with the notion that Old Tamil arici is the source of the Greek term, and proposes that it was borrowed from descendants of Proto-Dravidian *wariñci instead. The varieties of rice are typically classified as long-, medium-, the grains of long-grain rice tend to remain intact after cooking, medium-grain rice becomes more sticky. Medium-grain rice is used for dishes, for risotto in Italy
9.
Maize
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Maize, also known as corn, is a large grain plant first domesticated by indigenous peoples in Mexico about 10,000 years ago. The six major types of corn are dent corn, flint corn, pod corn, popcorn, flour corn, the leafy stalk of the plant produces separate pollen and ovuliferous inflorescences or ears, which are fruits, yielding kernels or seeds. Maize kernels are used in cooking as a starch. Most historians believe maize was domesticated in the Tehuacan Valley of Mexico, recent research modified this view somewhat, scholars now indicate the adjacent Balsas River Valley of south-central Mexico as the center of domestication. The Olmec and Mayans cultivated maize in numerous varieties throughout Mesoamerica, cooked and its believed that beginning about 2500 BC, the crop spread through much of the Americas. The region developed a network based on surplus and varieties of maize crops. Nevertheless, recent data indicates that the spread of maize took place even earlier, according to Piperno, A large corpus of data indicates that it was dispersed into lower Central America by 7600 BP and had moved into the inter-Andean valleys of Colombia between 7000 and 6000 BP. Since then, even earlier dates have been published, the study also demonstrated that the oldest surviving maize types are those of the Mexican highlands. Later, maize spread from this region over the Americas along two major paths and this is consistent with a model based on the archaeological record suggesting that maize diversified in the highlands of Mexico before spreading to the lowlands. Before they were domesticated, maize plants only grew small,25 millimetres long corn cobs, Maize is the most widely grown grain crop throughout the Americas, with 361 million metric tons grown in the United States in 2014. Approximately 40% of the crop—130 million tons—is used for corn ethanol, genetically modified maize made up 85% of the maize planted in the United States in 2009. After the arrival of Europeans in 1492, Spanish settlers consumed maize and explorers and traders carried it back to Europe, Spanish settlers far preferred wheat bread to maize, cassava, or potatoes. Maize flour could not be substituted for wheat for bread, since in Christian belief only wheat could undergo transubstantiation. At another level, Spaniards worried that by eating indigenous foods, which they did not consider nutritious, that not only would they weaken, despite these worries, Spaniards did consume maize and archeological evidence from Florida sites indicate they cultivated it as well. Maize spread to the rest of the world because of its ability to grow in diverse climates and it was cultivated in Spain just a few decades after Columbuss voyages and then spread to Italy, West Africa and elsewhere. The word maize derives from the Spanish form of the indigenous Taíno word for the plant and it is known by other names around the world. The word corn outside North America, Australia, and New Zealand refers to any cereal crop, in the United States, Canada, Australia, and New Zealand, corn primarily means maize, this usage started as a shortening of Indian corn. Indian corn primarily means maize, but can more specifically to multicolored flint corn used for decoration
10.
Barley
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Barley, a member of the grass family, is a major cereal grain grown in temperate climates globally. It was one of the first cultivated grains, particularly in Eurasia as early as 10,000 years ago, Barley has been used as animal fodder, as a source of fermentable material for beer and certain distilled beverages, and as a component of various health foods. It is used in soups and stews, and in barley bread of various cultures, Barley grains are commonly made into malt in a traditional and ancient method of preparation. In 2014, barley was ranked fourth among grains in quantity produced behind corn, rice, the Old English word for barley was bære, which traces back to Proto-Indo-European and is cognate to the Latin word farina flour. The direct ancestor of modern English barley in Old English was the derived adjective bærlic, the first citation of the form bærlic in the Oxford English Dictionary dates to around 966 CE, in the compound word bærlic-croft. The underived word bære survives in the north of Scotland as bere, the word barn, which originally meant barley-house, is also rooted in these words. Barley is a member of the grass family and it is a self-pollinating, diploid species with 14 chromosomes. The wild ancestor of domesticated barley, Hordeum vulgare subsp, spontaneum, is abundant in grasslands and woodlands throughout the Fertile Crescent area of Western Asia and northeast Africa, and is abundant in disturbed habitats, roadsides and orchards. Outside this region, the barley is less common and is usually found in disturbed habitats. However, in a study of genome-wide diversity markers, Tibet was found to be a center of domestication of cultivated barley. Wild barley has a spike, upon maturity, the spikelets separate. Domesticated barley has nonshattering spikes, making it easier to harvest the mature ears. The nonshattering condition is caused by a mutation in one of two linked genes known as Bt1 and Bt2, many cultivars possess both mutations. The nonshattering condition is recessive, so varieties of barley that exhibit this condition are homozygous for the mutant allele, spikelets are arranged in triplets which alternate along the rachis. In wild barley, only the central spikelet is fertile, while the two are reduced. This condition is retained in certain cultivars known as two-row barleys, a pair of mutations result in fertile lateral spikelets to produce six-row barleys. Recent genetic studies have revealed that a mutation in one gene, two-row barley has a lower protein content than six-row barley, thus a more fermentable sugar content. High-protein barley is best suited for animal feed, Malting barley is usually lower protein which shows more uniform germination, needs shorter steeping, and has less protein in the extract that can make beer cloudy
11.
Anticline
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In structural geology, an anticline is a type of fold that is an arch-like shape and has its oldest beds at its core. A typical anticline is convex up in which the hinge or crest is the location where the curvature is greatest, anticlines can be recognized and differentiated from antiforms by a sequence of rock layers that become progressively older toward the center of the fold. Therefore, if age relationships between various rock strata are unknown, the term antiform should be used, the progressing age of the rock strata towards the core and uplifted center, are the trademark indications for evidence of anticlines on a geologic map. These formations occur because anticlinal ridges typically develop above thrust faults during crustal deformations, the uplifted core of the fold causes compression of strata that preferentially erodes to a deeper stratigraphic level relative to the topographically lower flanks. Motion along the fault including both shortening and extension of tectonic plates, usually also deforms strata near the fault and this can result in an asymmetrical or overturned fold. An antiform can be used to describe any fold that is convex up and it is the relative ages of the rock strata that separate anticlines from antiforms. The hinge of an anticline refers to the location where the curvature is greatest, the hinge is also the highest point on a stratum along the top of the fold. The culmination also refers to the highest point along any geologic structure, the limbs are the sides of the fold that display less curvature. The inflection point is the area on the limbs where the curvature changes direction, the axial surface is an imaginary plane connecting the hinge of each layer of rock stratum through the cross section of an anticline. If the axial surface is vertical and the angles on each side of the fold are equivalent, if the axial plane is tilted or offset then the anticline is asymmetrical. An anticline that is cylindrical has a well-defined axial surface, whereas non-cylindrical anticlines are too complex to have an axial plane. If the angle between the limbs is large, then the fold is a fold, but if the angle between the limbs is small, then the fold is a tight fold. If an anticline plunges, it will form Vs on a map view that point in the direction of plunge. A plunging anticline has a hinge that is not parallel to the earths surface, all anticlines and synclines have some degree of plunge. Periclinal folds are a type of anticlines that have a well-defined, folds in which the limbs dip toward the hinge and display a more U-like shape are called synclines. They usually flank the sides of anticlines and display opposite characteristics, a synclines oldest rock strata are in its outer limbs, the rocks become progressively younger toward its hinge. A monocline is a bend in the resulting in a local steepening in only one direction of dip. Monoclines have the shape of a carpet draped over a stairstep, an anticline that has been more deeply eroded in the center is called a breached or scalped anticline
12.
Germination
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Germination is the process by which a plant grows from a seed. The most common example of germination is the sprouting of a seedling from a seed of an angiosperm or gymnosperm, in addition, the growth of a sporeling from a spore, such as the spores of hyphae from fungal spores, is also germination. Thus, in a sense, germination can be thought of as anything expanding into greater being from a small existence or germ. The seed of a plant is a small package produced in a fruit or cone after the union of male and female reproductive cells. All fully developed seeds contain an embryo and, in most plant species some store of food reserves, some plants produce varying numbers of seeds that lack embryos, these are called empty seeds and never germinate. Dormant seeds are seeds that do not germinate because they are subject to external environmental conditions that prevent the initiation of metabolic processes. Under proper conditions, the seed begins to germinate and the embryonic tissues resume growth, Seed germination depends on both internal and external conditions. The most important external factors include right temperature, water, oxygen or air, various plants require different variables for successful seed germination. Often this depends on the seed variety and is closely linked to the ecological conditions of a plants natural habitat. For some seeds, their future germination response is affected by environmental conditions during seed formation, mature seeds are often extremely dry and need to take in significant amounts of water, relative to the dry weight of the seed, before cellular metabolism and growth can resume. Most seeds need enough water to moisten the seeds but not enough to soak them, the uptake of water by seeds is called imbibition, which leads to the swelling and the breaking of the seed coat. When seeds are formed, most plants store a reserve with the seed, such as starch, proteins. This food reserve provides nourishment to the growing embryo, when the seed imbibes water, hydrolytic enzymes are activated which break down these stored food resources into metabolically useful chemicals. Oxygen is required by the seed for metabolism. Oxygen is used in respiration, the main source of the seedlings energy until it grows leaves. Oxygen is a gas that is found in soil pore spaces, if a seed is buried too deeply within the soil or the soil is waterlogged. Temperature affects cellular metabolic and growth rates, Seeds from different species and even seeds from the same plant germinate over a wide range of temperatures. Seeds often have a range within which they will germinate
"Aleurone". New International Encyclopedia. 1905.
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