...bird is hunted by a hawk. A food chain clearly shows this pathway of food consumption. You could probably think of another food chain for a forest ecosystem. In fact, many different food chains exist in ecosystems. Although there are many different kinds of food chains, each food chain follows the same general pattern. A link in a food chain is called a trophic, or feeding level. The trophic levels are numbered as the first, second, third, and fourth levels, starting with the producers. Each of the trophic levels is occupied by a certain kind of organism. Producers are always in the first trophic level since they do not feed on another organism. Consumers occupy the rest of the trophic levels. The second trophic level is the first consumer in the food chain and is called a primary consumer. Primary consumers eat plants and are therefore herbivores or omnivores. The next consumer in the food chain is the secondary consumer. The secondary consumer is in the third trophic level. Since the secondary consumer feeds on another animal, it is a carnivore or an omnivore. Similarly, the tertiary consumer occupies the fourth trophic level, and is a carnivore. The last link in a food chain...
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...1.4.6 Energy Flow Worksheet What is an ecosystem? An ecosystem is a _________________________________________ with ___________________ and their __________________________ within _____________________, e.g. woodland, etc. Energy Flow Ecosystems are unable to function unless there is a constant ________________________________ _____________________. Where does this energy come from? __________________ The Sun The sun is the _________________________________________________ for our planet. Energy Flow is the _________________________________________________ from one organism to the next in an ecosystem due to ________________, e.g. along a food chain Feeding allows _____________________________________________________ in an ecosystem. Energy flow in the ecosystem Food Chain Is a flow diagram that begins with a _______________ and shows how _____________________ is passed through a series of ______________________________________. Each organism feeds on the one before it. A food chain ends when there is _____________________________________________________. An example of a food chain: __________ ( ____________ ( ______ A Grazing food chain is one where the __________________________________ e.g. ________________ ( grasshoppers ( frogs ( hawks ...
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...chain can be thought of as a transfer of food from trophic level to trophic level (fig. 49.1). Food chains rarely are unbranched since several different primary consumers may feed on the same plant species and a primary consumer may eat several species of plants. The feeding relationships are usually woven into elaborate food webs within an ecosystem. Ecological Pyramids 1. A pyramid of productivity has trophic levels stacked in blocks proportional in size to the energy acquired from the level below. Food chains are usually bottom heavy since only 10% of energy is transferred. 2. A biomass pyramid has each tier symbolising the total dry weight of all organisms in an ecosystem's levels at any given time. Biomass represents chemical energy stored in the organic matter of a trophic level. Most narrow sharply from producers at the base to top-level carnivores at the top. Some aquatic systems are inverted since producers can have high turnover rates. They grow rapidly but are consumed rapidly, leaving little standing biomass. Biomass of top-level carnivores is usually small compared to the total biomass of producers and lower-level consumers. Food chains are limited to 3-5 links due to the multiplicative loss of energy. This also limits the biomass of top-level carnivores that can be supported. Only about 1/1000 of the chemical energy fixed by photosynthesis flows through a food web to a tertiary consumer, only 3 -5 trophic levels can be supported since biomass at the apex...
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...Week 3 ILab Joy Major Exercise 1: A biomass pyramid is a diagram that shows the flow of energy through each trophic level of a food chain by quantifying the amount of biomass present at each trophic level. As a general rule, 90% of the energy is lost as you move through each trophic level. The levels move as follows: primary producers to primary consumers/herbivores to secondary consumers (predators) to tertiary consumers (top of the food chain). For example, in an eastern deciduous forest, if the primary producers (i.e., deciduous trees, shrubs, and grasses) produce 10,000 kilocuries per square meter a year then the kilocalories available at the primary consumer level (i.e., bugs, deer, rabbits, small birds) will be 1,000 kilocalories; followed by 100 at the secondary consumer level (i.e., foxes, owls, skunks, large birds) and 10 at the tertiary consumer level (i.e., bears). An example of this flow of energy can be found below. Exercise 2: Mount St. Helens has revealed some important factors that influence how an ecosystem can recover from such a cataclysmic eruption. One mudflow had cut through a forest, so it was surrounded by existing vegetation and recovered relatively quickly. The seasonal timing was a key factor because spring was late in coming to Mount St. Helens that year, and so there were still drifts of snow covering the understory of many sections of the forest, protecting the plant and animal species buried beneath them. The snowmelt also protected...
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...Biology – Module 1 – A Local Ecosystem The distribution, diversity and numbers of plants and animals found in ecosystems are determined by biotic and abiotic factors. Compare the abiotic characteristics of aquatic and terrestrial environments. An aquatic environment is one that consists in water. The abiotic characteristics of an aquatic environment include: Buoyancy – This refers to the upward pressure (or thrust) that is applied on the organism by its medium. Buoyancy is determined by the density of the medium and determines the floating ability of an organism. Water provides sufficient buoyancy for many organisms, e.g., the jellyfish. If a jellyfish is taken out of water and placed on land it will disintegrate by spreading apart. Thus, the water provides enough buoyancy (pressure) in order to keep the shape of the jellyfish. Pressure – This is the downward force that is applied on an organism by its medium. In water, the pressure is dependent on the depth. Organisms that live at the bottom of the ocean experience the effects of extreme pressure and they must have specific adaptations that enable them to survive in such harsh environments. Temperature Variations – Usually in an aquatic environment there are minimal temperature variations to that compared with terrestrial environments. The temperature variations also depend on the size of the body of water; a large body of water will experience much less temperature variations than a smaller body...
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...products, food energy and organic compounds are transferred from the plants to the animals. Food Chains and Food Webs In the living world, every form of life is food for another. Food chains and webs show how food and energy are passed between species. Food Chain A food chain is a food pathway that links different species in a community. In a food chain, energy and nutrients are passed from one organism to another. Food Chains rarely contain more than six species because amount of energy passed on diminishes at each stage, or trophic level. The longest chains usually involve aquatic animals. In a food chain, an animal passes on only about 10 percent of the energy it receives. The rest is used up in maintaining its body, or in movement, or it escapes as heat. The amount of available energy decreases at every trophic level, and each level supports fewer individuals than the one before. This results in a pyramid of numbers with many organisms at the bottom and few at the top. Food Web A community of...
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...at a rate proportional to its size. Life history strategy The position a population of organisms occupies on the continuum between producing a large number of “inexpensive” offspring and a small number of “expensive” offspring. Logistic growth A model of population growth in which growth slows as the population approaches the carrying capacity of its habitat. Niche The total set of biotic and abiotic resources a species uses within a community. Population A group of individuals of a single species that occupies a given area. Producer An organism that makes organic molecules from inorganic materials and energy. Symbiosis A situation in which individuals of two species live in close association with one another. Trophic level One of the feeding levels in a food chain, including producers, primary consumers, secondary consumers, tertiary consumers, and so forth. Review Questions 21.1 Organisms and Their Environment 1. What is ecology? 2. Does an organism’s environment include only nonliving components? yes 3. What is the difference between a community and an ecosystem? The difference between a community and an ecosystem is one (community) is an area where organisms live and the other...
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...WEEK 8 Discuss the similarities and differences between the Mesopotamian ziggurat and the Egyptian pyramid both in style and function. Man has a tendency to build large monumental things, not only today, but also during our ancient past. The Sumerians and the Egyptians are two cultures, from our past, that have accomplished these feats. The Sumerian ziggurats and Egyptian pyramids have some similarities and differences. The ziggurats and the pyramids have some similarities. They are both examples of the massive structures that were built in support of their cultural or religious beliefs. They were both built with a great deal of manpower with no use of any big machinery that we are familiar with today. Their society's leaders commissioned in building these massive structures were: the king of the Sumerian civilization for the ziggurats and the pharaoh of the Egyptian civilization for the pyramids. Their similarities pretty much ends here. At a closer look, the ziggurats and the pyramid had many differences. The pharaohs, in preparation for his death, built the pyramids as place for his tomb and his priced possessions and servers (to ensure that his needs are met in the afterlife) and also for his queen. It is said that the pharaoh ruled in the authority of the God and that the pyramid would help him ascend to the Gods. The Sumerian king had the ziggurats built for use as a place for worship, like a temple, for the Sumerian society. One story also suggest that...
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...Harvard Management Communication Letter A Newsletter from Harvard Business School Publishing Tools, Techniques, and Ideas for the Articulate Executive Article Reprint No. C0504C The Best Memo You’ll Ever Write by Holly Weeks This document is authorized for use by Ethan Beldengreen-Karas, from 8/30/2012 to 12/1/2012, in the course: BUS 365: Communication and Professional Development - Epstein/Graves (Fall 2012), Emory University. Any unauthorized use or reproduction of this document is strictly prohibited. For a complete list of Harvard Business School Publishing newsletters: http://newsletters.harvardbusinessonline.org For reprint and subscription information for Harvard Management Communication Letter: Call 800-988-0866 or 617-783-7500 http://hmcl.harvardbusinessonline.org For customized and quantity orders of reprints: Call 617-783-7626 Fax 617-783-7658 For permission to copy or republish: Call 12/1/2012, in the This document is authorized for use by Ethan Beldengreen-Karas, from 8/30/2012 to 617-783-7587 course: BUS 365: Communication and Professional Development - Epstein/Graves (Fall 2012), Emory University. Any unauthorized use or reproduction of this document is strictly prohibited. Writing The Best Memo You’ll Ever Write Every memo—or report or e-mail—is important in today’s business environment. If you keep in mind that readers are content driven, time pressed, and decision focused, you can write right—every time. by...
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...1. In this assignment we will evaluate settings for events with common characteristics between the periods of ancient civilizations, Paleolithic, and Neolithic to Egyptian civilization. What we are looking for are changes in these cultures, if any, how and why did the change occur and what may have triggered them. As a civilization progresses and evolves they bring with them common characteristics from their predecessors. Some of these characteristics are government, economy, food and supplies, social equality, and religion. The Paleolithic were among the first to inhabit the regions of Western Europe stretching to Egypt. They were also the first to adapt to the land, hunt and gathered, and also experimented with art, textures, and colors. The Paleolithic didn’t have a form of government more of a tribe family which were ruled by the male and differed from city to city. They also didn’t have an economic system or a way to trade goods. However they were among the many to learn how to evolve their weapons into more effective ways to hunt. The Neolithic civilization carried these same common characteristics, but evolved it and organized it a lot better. There form of government was evolved into a chief and council system. Hunting and gathering was also in existence but were evolved to farming and creating surpluses. Art was also apparent more so in sculptures, textures, and more discovered materials. Also a barter system was established where one could trade their precious items...
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...without the help of machinery. The main reason for this question was because each pyramid was composed of millions of limestone blocks each weighing 25 to 80 tons each and was located on the west side of the Nile. Experts have also talked a lot about the methods by which each block was raised into position. It was theory that wooden and bronze levers were used to move the blocks, a system of ramps, terrestrials or just millions of workers. There was also debate on how did they get these huge stones from the quarries into the middle of the desert. Some archaeologists believed that they used large boats, traveling the Nile or just simply rolled and drug them. I believe the theory of a million of workers is possible but whether they dragged, lifted or even rolled each stone into place is not.The Greeks believed slaves was used, but modern Egyptologists accept that it was thousands of skilled workers. Verner posited that the labor was organized into a hierarchy, consisting of two gangs of 100,000 men, divided into five groups of 20,000 men each, which may have been further divided according to the skills of the workers. So through research I believe these men may have used a system of ramps. Most archaeologists agreed that a system of ramps must have been used to drag the millions of blocks into their positions in the various pyramids. There are traces of these ramps around some of the older pyramids to suggest that at least five different systems of ramp might have been used. The...
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...* In the Lake Michigan food web, is it possible to identify the most important producer? Why or why not? It is not possible to identify the most important producer. There are multiple consumers which are consumed by several different primary consumers. The image was blurry so it was difficult to determine what everything was in the food web. * What would happen if there was a change in the population size for any one of the producers (either an increase or a decrease)? How could these changes impact other producers and organisms on other trophic levels? If there were an increase in population in any one of the producers, they would begin to dominate the other producers and therefore would increase the number of consumers which feed on the producer. If there were a decrease in one of the producers then there may be a decrease in consumers that are reliant on the producer for food or the consumer could choose a different producer. If the consumer chose a different producer for food, the result would be a depletion of this producer. It could end up like a snowball effect by one affecting the other. * Provide at least two types of impacts that humans could have on this food web. Burning of coal can cause air pollution which can cause acid rain and change the ecosystem of the lake. http://www.ucsusa.org/clean_energy/coalvswind/c02b.html Dumping of toxins into the lake which could disrupt producers and have an effect on producers. * Read the description of the sea...
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...larvae are eaten by mice d) there are “bumper years” of lyme disease e) ticks like to feed on human blood Answer: a 5) The Environmental Science textbook outlines the relatively simple food chain that exists in hot springs such as in Yellowstone National Park, including the following organisms: (A) herbivorous flies (B) carnivorous flies (C) decomposers (D) photosynthetic bacteria What would be the correct order of these organisms from lowest trophic level to highest trophic level: a) C, A, B, D b) B, A, D, C c) D, A, B, C d) B, A, C, D e) C, D, A, B Answer: c 6) Which of the following is an example of three different species on three different trophic levels, listed from lowest level to highest: a) shrubs, trees, giraffes b) humans, cows, grass c) sharks, herbivorous fish, carnivorous fish d) moss, reindeer, wolves e) dirt, corn, humans Answer: d 7) The most basic processes in an ecosystem are: a) photosynthesis and respiration b) transport and storage of food c) trophic chains and storage of food d) flow of energy and cycling of chemical elements e) waste decomposition and cycling of energy...
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...Food web A food web (or food cycle) is the natural interconnection of food chains and generally a graphical representation (usually an image) of what-eats-what in an ecological community. Another name for food web is a consumer-resource system. Ecologists can broadly lump all life forms into one of two categories called trophic levels: 1) the autotrophs, and 2) the heterotrophs. To maintain their bodies, grow, develop, and to reproduce, autotrophs produce organic matter from inorganic substances, including both minerals and gases such as carbon dioxide. These chemical reactions require energy, which mainly comes from the sun and largely by photosynthesis, although a very small amount comes from hydrothermal vents and hot springs. A gradient exists between trophic levels running from complete autotrophs that obtain their sole source of carbon from the atmosphere, to mixotrophs (such as carnivorous plants) that are autotrophic organisms that partially obtain organic matter from sources other than the atmosphere, and complete heterotrophs that must feed to obtain organic matter. The linkages in a food web illustrate the feeding pathways, such as where heterotrophs obtain organic matter by feeding on autotrophs and other heterotrophs. The food web is a simplified illustration of the various methods of feeding that links an ecosystem into a unified system of exchange. There are different kinds of feeding relations that can be roughly divided into herbivory, carnivory, scavenging and...
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...throughout an ecosystem. Each and every one of the overlapping, and organized food chains in the same ecosystem create a food web. "A food web is a graphical description of feeding relationships among species in an ecological community, that is, of who eats whom"( J. Duffy, 2013 ). Trophic levels consist of a group of organisms in the food webs. Also, this trophic levels are divided into three levels and this levels are decomposers, consumers, and producers. The first trophic level is known as Producers. Also, they create their food and they don't turn to other organism, and they also called autotrophs. Normally autotrophs create food using a process known as photosynthesis, and that create a nutrient known as glucose, and these consist of water , carbon dioxide, and sunlight. There are different types of autotroph but plants are the most known type. One larger plant that's known as seaweed is a autotroph. Also, tiny organisms living in the deep-sea called Phytoplankton, are also autotrophs. There are various bacteria that are autotrophs. Example, in a lively volcanoes exist bacteria and they use sulfur to put together its own food. This procedure is known as chemosynthesis. The following trophic levels consist of organism that consume producers. This animals or creatures are known as consumers. Main consumers are known to be herbivores. Herbivores consume plant life, seaweed, and others producers. Deer, cows, and even elephants are herbivores living in a ecosystem of grassland...
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