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what do guard cells do? | Yahoo Answers

appeared in the Ediacaran, and Cambrian Period skeletons became a key aspect of the coming arms race between predator and prey. appeared in which about was transferred to the animal that ate it. Unlike the internal skeletons that characterized fish, amphibians, reptiles, birds, and mammals, the first skeletons were external. Hard shells protected from predation, and the bigger the animal, the more likely it would survive (but a bigger animal also meant a bigger energy windfall if it could be eaten). But size presented immense challenges. Similar to how complex cells needed to , increasing size presented numerous problems to early complex life. How could a large organism supply energy and other nutrients to its cells? Remove waste? Move? Life solved the problems by making structures and organs from specialized cells. By the Cambrian Period’s end, animals had developed skeletons, gills, muscles, brains, circulatory systems, digestive and eliminative systems, nervous systems, respiratory systems, and internal organs which included eyes, livers, kidneys, etc.

One of the paired epidermal cells that control the opening and closing of a stoma in plant tissue.

At this juncture, I will ask my readers to perform an exercise that I first saw described by Peak Oil advocate , which is to lay aside data and graphs and just think about how energy makes everything in our daily lives possible. Think about your food, water, mode of transportation, and materials that comprise your home and possessions, and think of the role that energy played in providing them. Think about the energy that you use each day in powering your home and in your transportation, even if it is just walking. Then imagine running out of energy. When you flipped on a light switch, nothing happened. When you turned on the tap, no water came out. Your refrigerator stopped working, food deliveries to your community ceased, and no electricity, oil, gas, coal, or even wind or water power was available. Everything in your life would come to a sudden halt. When people have tried to demote energy below spirituality, social relations, or even made it irrelevant to economics, my question is for them to see what they can forego the longest: prayer/meditation, social interaction, sex, or energy. The fossil fuels burned to power industrial civilization provide several hundred energy slaves for each American and no less than hundreds per person in every industrialized nation. All that those energy-leveraged humans do is direct the energy, like holding the reins of a gigantic beast that each person rides each day. Airline pilots half-joke that they begin their workday by strapping jet airliners to their waists. Without that energy to direct in the myriad ways that industrialized humans use it, modern civilization would come to an abrupt end.

10/05/2010 · what do guard cells do

In very real terms, economic production relies on work performed, and the is what economic work is rooted in. Moving an automobile or airplane requires work. Moving water requires work, as does running a household appliance or computer. Electricity can power a machine or a light. Energy consumption work to be performed, and that is why . Neoclassical economists, with their supply and demand curves and other social/monetary constructs generally disregard that relationship, as they abandoned the real world for social theories, which is why . Those all-too-rare economists challenging neoclassical economics from a scientific perspective focus on energy above all else, and the labor and technological capital ( capital, not the accounting claim on it that capitalists have) that use that energy to turn material resources into useful products and services. They focus on the real economy and actual human benefit, in what I call the anthropocentric economy.

Above all else, the Industrial Revolution rode on the energy of hydrocarbon fuels. A very strong American, hauling water, can perform about one kilowatt-hour of work in a 10-hour day, and a typical American about half that. An electric pump could do the same work for less than 1/2000th of the worker’s wage cost. Not only could the Industrial Revolution’s energy technologies work far more cheaply than humans could, they could perform feats far beyond what muscle power could achieve. A slave-borne palanquin never attained a speed of 100 KPH, nor could it fly or travel to the moon. The energy of fossil fuels allowed for previously unimaginable feats of strength and speed, and materials and machines were created that would have such as plastics and electronic equipment. The relationship between energy use and economic output, measured in (“GDP”), is nearly linear, and . The is a typical example, as shown below. The near-linear relationship is primarily due to energy-driven machines performing work; market prices reflect the work used in the production of goods and services. (Source: Wikimedia Commons)

Does guard cell assist photosynthesis;

In 2003, when I began studying , the , and they articulated the difficulties that I had with mainstream economics since . A textbook published in 2011 by an economist and ecologist analyzed the disconnection between economists and the real world, and the way that economic schools have ignored energy was, in the opinion of the authors, their most grievous error. I do not take overarching conspiracy theories very seriously, as they do not adequately explain how most people act. People blindly and uncaringly performing their jobs are how most of the FE suppression that I survived was inflicted. Structural features, , explain most activity. However, that did not mean that those at the top did not know what they were doing, or even those further down the command chain, and my life’s turning point was when a public official . Organized suppression is , in my experience. Those doing most of the dirty work really do not know whose interests they serve or , and most do not even care much as long as it pays well, which was .

Going back to the beginnings of the to how the to the , what Marx called separating the workers from the means of production had to be performed first so that the ownership class could form. With the workers put in their place, then the “owners” could create instruments of ownership and trade them. Thus began stock markets. Similar to how , when stock markets formed, owners became divorced from operations. In corporate America, for instance, there are theoretical governance mechanisms such as boards of directors and company officers that answer to the shareholders, but the relationship is often more theoretical than actual, and “cooking the books” to make management look good and inflate the stock price is as old as corporations. Dealing with that aspect of corporations is largely what I do to make a living. I have lived through several major financial scandals in my career, and they .

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Photosynthesis/ATP/cellular respiration Flashcards | …

Although Enlightenment philosophers acknowledged their debt to Newton (the world’s most towering intellectual of his time and one of history’s greatest scientists and mathematicians), he saw nothing improper with the slave trade and in 1720. When machines began reproducing human labor, the abolition of slavery also began, as it made unskilled labor uneconomical. Slavery, particularly the genocidal forms inflicted by Europe, were viable only for situations in which little professional skill was needed. Slavery worked best in mine and plantation work that used illiterate and often-expendable people. What became the USA was unique in the European age of slavery, in that tobacco operations, unlike sugar plantations, had more seasonal labor demands. Moreover, the environment of southeast North America was conducive to long-lived and fertile slaves, so that they could reproduce. Consequently, what became the USA was a , with its large slave population largely bred, not captured. People born into slavery are easier to keep enslaved than those born free, but they had to be kept illiterate and at low skill levels, or else they might desire freedom and obtain it. Late in the American era of slavery, some slaves were taught to read, but generally only one book, which justified slavery: the Bible. All the way to , apologists for slavery used Biblical passages to justify it. Many also justified antebellum slavery with economic arguments, stating that people took better care of something they owned rather than something they rented.

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No historian has argued that England had a grand plan of industrialization, but the Epochal Event was the culmination of several trends. Although the science of energy had yet to be invented, the obvious advantages of watermills, windmills, and sailing ships were not lost on people, and the control of arable land, forests, low-energy transportation lanes, workforces, and markets was always the road to riches from onward. People knew what they were doing, even if they had little or no long-term perspective.

How does photosynthesis help maintain homeostasis

By 1300, Earth was cooling down, High Middle Ages Europe was largely deforested, and nearly all arable land was under the plow. Europe had reached the Malthusian limit of its means of preindustrial production. The 1300s were a century of unending calamity for Europe, beginning with famines in 1304, 1305, and 1310, and a that lasted three years. Famines visited Europe at least once a generation in the 1300s. In 1337, England and France . Those events were only a hint at what lied ahead. Plagues and famines tend to be conjoined: weakened bodies are susceptible to disease. The Black Death pandemic probably originated in war-torn and famine-plagued China . In 1346, it reached Europe. By 1350, and . War, famine, and epidemics were so prevalent in the 1300s that the became an art form in the 1400s and 1500s, after the . Europe became a hell on Earth. But the work that watermills performed was not subject to famine and disease, and the work of millions of “energy slaves” surely helped hold Europe together. Labor was in such shortage after the catastrophes that .

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