36. 03. 01 Всэ заочное 24. 01. 2022 I. Прочтите текст и ответьте на вопросы
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36.03.01 ВСЭ /заочное/ 24.01.2022 I. Прочтите текст и ответьте на вопросы: Text 1 Ecosystem Ecosystem - the complex of living organisms, their physical environment, and all their interrelationships in a particular unit of space. The principles underlying the study of ecosystems are based on the view that all the elements of a life-supporting environment of any size, whether natural or man-made, are parts of an integral network in which each element interacts directly or indirectly with all others and affects the function of the whole. All ecosystems are contained within the largest of them, the ecosphere, which encompasses the entire physical Earth (geosphere) and all of its biological components (biosphere). An ecosystem can be categorized into its abiotic constituents, including minerals, climate, soil, water, sunlight, and all other nonliving elements, and its biotic constituents, consisting of all its living members. Linking these constituents together are two major forces: the flow of energy through the ecosystem, and the cycling of nutrients within the ecosystem. The fundamental source of energy in almost all ecosystems is radiant energy from the sun. The energy of sunlight is used by the ecosystem's autotrophic, or self-sustaining, organisms. Consisting largely of green vegetation, these organisms are capable of photosynthesis - i.e., they can use the energy of sunlight to convert carbon dioxide and water into simple, energy-rich carbohydrates. The autotrophs use the energy stored within the simple carbohydrates to produce the more complex organic compounds, such as proteins, lipids, and starches, that maintain the organisms' life processes. The autotrophic segment of the ecosystem is commonly referred to as the producer level. Organic matter generated by autotrophs directly or indirectly sustains heterotrophic organisms. Heterotrophs are the consumers of the ecosystem; they cannot make their own food. They use, rearrange, and ultimately decompose the complex organic materials built up by the autotrophs. All animals and fungi are heterotrophs, as are most bacteria and many other microorganisms. Together, the autotrophs and heterotrophs form various trophic (feeding) levels in the ecosystem: the producer level, composed of those organisms that make their own food; the primary-consumer level, composed of those organisms that feed on producers; the secondary-consumer level, composed of those organisms that feed on primary consumers; and so on. The movement of organic matter and energy from the producer level through various consumer levels makes up a food chain. For example, a typical food chain in a grassland might be grass (producer) → mouse (primary consumer) → snake (secondary consumer) → hawk (tertiary consumer). Actually, in many cases the food chains of the ecosystem overlap and interconnect, forming what ecologists call a food web. The final link in all food chains is made up of decomposers, those heterotrophs that break down dead organisms and organic wastes. A food chain in which the primary consumer feeds on living plants is called a grazing pathway; that in which the primary consumer feeds on dead plant matter is known as a detritus pathway. Both pathways are important in accounting for the energy budget of the ecosystem. As energy moves through the ecosystem, much of it is lost at each trophic level. For example, only about 10 percent of the energy stored in grass is incorporated into the body of a mouse that eats the grass. The remaining 90 percent is stored in compounds that cannot be broken down by the mouse or is lost as heat during the mouse's metabolic processes. Energy losses of similar magnitude occur at every level of the food chain; consequently, few food chains extend beyond five members (from producer through decomposer), because the energy available at higher trophic levels is too small to support further consumers. The flow of energy through the ecosystem drives the movement of nutrients within the ecosystem. Nutrients are chemical elements and compounds necessary to living organisms. Unlike energy, which is continuously lost from the ecosystem, nutrients are cycled through the ecosystem, oscillating between the biotic and abiotic components in what are called biogeochemical cycles. Major biogeochemical cycles include the water cycle, carbon cycle, oxygen cycle, nitrogen cycle, phosphorus cycle, sulfur cycle, and calcium cycle. Decomposers play a key role in many of these cycles, returning nutrients to the soil, water, or air, where they can again be used by the biotic constituents of the ecosystem. The orderly replacement of one ecosystem by another is a process known as ecosystem development, or ecological succession. Succession occurs when a sterile area, such as barren rock or a lava flow, is first colonized by living things or when an existing ecosystem is disrupted, as when a forest is destroyed by a fire. The succession of ecosystems generally occurs in two phases. The early, or growth, phase is characterized by ecosystems that have few species and short food chains. These ecosystems are relatively unstable but highly productive, in the sense that they build up organic matter faster than they break it down. The ecosystems of the later, or mature, phase are more complex, more diversified, and more stable. The final, or climax, ecosystem is characterized by a great diversity of species, complex food webs, and high stability. The major energy flow has shifted from production to maintenance. 1. How does energy flow through communities? Energy flows through the ecosystem through different levels, starting with the process of photosynthesis. The process ends when the carnivores die and get decomposed, thereby becoming food for plants and starting the cycle again. 2. What is a trophic level? Trophic level is a feeding level in the ecosystem. 3. How do nutrients move within ecosystems? Nutrients are cycled through the ecosystem, oscillating between the biotic and abiotic components in what are called biogeochemical cycles. Decomposers play a key role in many of these cycles, returning nutrients to the soil, water, or air, where they can again be used by the biotic constituents of the ecosystem. 4. What trophic levels do you know? I know the following trophic levels: the producer level, composed of those organisms that make their own food; the primary-consumer level, composed of those organisms that feed on producers; the secondary-consumer level, composed of those organisms that feed on primary consumers. 5. Give your own example of a food chain. grass (producer) → deer (primary consumer) → tiger(secondary consumer) 6. Explain the phases of ecological succession. The succession of ecosystems generally occurs in two phases. The early, or growth, phase is characterized by ecosystems that have few species and short food chains. These ecosystems are relatively unstable but highly productive. The ecosystems of the later, or mature, phase are more complex, more diversified, and more stable. II. Give definitions to the following concepts from the text 1. Ecosystem is the complex of living organisms, their physical environment, and all their interrelationships in a particular unit of space Abiotic constituents are nonliving elements including minerals, climate, soil, water, sunlight, and all other Biotic constituents are all living members of the ecosystem Autotrophs are primary producers, organisms that produce complex organic compounds Heterotrophs are the consumers of the ecosystem; they cannot make their own food Trophic level is a feeding level in the ecosystem Food chain is the movement of organic matter and energy from the producer level through various consumer levels Decomposers are heterotrophs that break down dead organisms and organic wastes. Grazing pathway is a food chain in which the primary consumer feeds on living plants Detritus pathway is a food chain in which the primary consumer feeds on dead plant matter Nutrients are chemical elements and compounds necessary to living organisms Ecological succession is a process of the orderly replacement of one ecosystem by another III. Read the Text 2. Make a summary of it. Text 2 A Balanced Diet More and more people today are taking greater responsibility for their own health. We now recognize that we can influence our health by making an improvement in lifestyle – a better diet, more exercise and reduced stress. Our health and general wellbeing is very much determined by what we eat. Unfortunately, we can’t see the results of a bad diet immediately. Few people realize how closely their health is linked to what they eat and how often they eat. You should learn how to balance your food intake. By matching your diet to your lifestyle and developing better eating habits you can keep yourself in the best health. The body needs many different nutrients. These are various substances necessary to provide energy and the materials for growth, bodybuilding, and body maintenance. Not all foods contain all nutrients. So it is not just the quantity of food eaten that is important, but also the variety. People who have enough food available may still become ill because they are eating too much of one kind of food and not enough of another. To stay healthy, we need to eat a balanced diet. This means a diet containing the right proportions of the main nutrients: carbo19 hydrates, proteins, fats, fibre, minerals, vitamins, and fluids. Many foods are a mixture of these basic nutrients. A balanced diet also contains enough energy (in the form of food) to power the chemical reactions of living. The three main sources of energy are carbohydrates, protein, and fat. Carbohydrates – are a good source of energy for our bodies. Good sources of carbohydrates are: whole grain, fresh fruits and vegetables, white bread, white rice, sweetened fruit drinks, sweets and desserts. Protein foods help to build strong muscles and bones. Foods that are good sources of protein include: meat and poultry without the extra fat or skin, fish, low-fat cheese, and eggs, dried peas or beans, kidney, white, soy products and nuts. Too much fat can make you gain weight. Choose fats that keep your heart healthy: small portions of salad dressing, low-fat mayonnaise and margarine, nuts, olives, and vegetable oil. Your height, weight, age, and activity will affect how much food you need to eat each day to stay at a healthy weight. Everyone is different. It’s best to spread your food out over the day. Being active and eating smaller amounts of food can help you be healthy. Summary The text under review is named “Balanced diet”. It consists of 7 paragraphs. The text mainly deals with the problem of balanced diet. At the beginning of the text the author draws our attention to the fact that more and more people today are taking greater responsibility for their own health. At the end of the second paragraph the author states that not all foods contain all nutrients. In the third paragraph the author gives us a detailed description of the main nutrients that every balanced diet should contain. The author makes it clear that the three main sources of energy are carbohydrates, protein, and fat and explains what products can help to keep our hearts healthy. At the end of the text the author mentions that all people are different but being active and eating smaller amounts of food is a good advice for everyone. IV. Переведите предложения на русский язык: 1. Man and animals breathe in oxygen and breathe out carbon dioxide. 2. “Ecosystem” means organisms living in a particular environment, such as a forest or a coral reef, and the physical parts of the environment that affect them. 3. Today, forests occupy around a third of Earth's land area, represent over 60% of the leaf area of land plants, and contain 70% of the carbon present in living things. They are home to more than half the world's terrestrial species. 4. Wood and paper consumption, primarily in industrialized countries, is one of the primary factors driving global deforestation. 5. Deforestation is a major contributor to the habitat loss that continues to threaten endangered species across the planet. 6. Today, there are only three great forests left on Earth: the Amazon Forest of Brazil, and the boreal forests in Russia and Canada. 7. All of Earth's oxygen is produced by photosynthesis, the process plants use to combine water and carbon dioxide to create glucose (their own food) and oxygen. 8. Polar ecosystems are home to an array of plants and animals that survive in some of the most extreme conditions in the world. Перевод: 1. Человек и животные вдыхают кислород и выдыхают углекислый газ. 2. "Экосистема" подразумевает организмы, живущие в определенной среде, такой как лес или коралловый риф, и физические части среды, которые влияют на них. 3. Сегодня леса занимают около трети суши Земли, на них приходится более 60% площади листьев наземных растений, и в них содержится 70% углерода, присутствующего в живых организмах. Они являются домом для более чем половины наземных видов животных. 4. Потребление древесины и бумаги, главным образом в промышленно развитых странах, является одним из основных факторов глобального обезлесения. 5. Обезлесение является основным фактором потери среды обитания, которая продолжает угрожать исчезающим видам на всей планете. 6. Сегодня на Земле осталось только три великих леса: бразильская Амазонка и бореальные леса в России и Канаде. 7. Весь кислород на Земле производится путем фотосинтеза - процесса, с помощью которого растения соединяют воду и углекислый газ для получения глюкозы (собственной пищи) и кислорода. 8. Полярные экосистемы являются домом для множества растений и животных, которые выживают в одних из самых экстремальных условий в мире. V. Make a written translation of the text. TUMORS OF THE SKIN AND SOFT TISSUES Cutaneous tumors are the most frequently diagnosed neoplastic disorders in domestic animals, in part because they can be identified easily and in part because the constant exposure of the skin to the external environment predisposes this organ to neoplastic transformation. Chemical carcinogens, ionizing radiation, and viruses all have been implicated, but hormonal and genetic factors may also play a role in development of cutaneous neoplasms. The skin is a complex structure composed of various epithelial (epidermis, adnexa), mesenchymal (fibrous connective tissues, blood vessels, adipose tissue), and neural and neuroectodermal tissues (peripheral nerve, Merkel cells, melanocytes), all with the potential of developing distinctive tumors. Because cutaneous tumors are so diverse, their classification is difficult and often controversial. There is also controversy regarding the criteria used to define whether a lesion that arises in the skin or soft tissues is neoplastic and, if so, whether it is benign or malignant. To avoid confusion, the following terms are used in this discussion: A hamartoma(nevus) is a localized developmental defect associated with enlargement of one or more elements of the skin. A sebaceous hamartoma, for example, refers to a localized region of the skin where sebaceous glands are extremely prominent and sometimes malformed. Although by strict definition, hamartomas are present at birth, they may occasionally take a long time to reach a size when they are clinically apparent and may not be diagnosed until an animal is mature. To confuse matters further, some lesions with clinical and histologic features of congenital hamartomas may develop in adult animals. Such “acquired” hamartomas are difficult to separate from benign epithelial and mesenchymal neoplasms. In human medical literature and some veterinary texts, the term “nevus” is used synonymously with hamartoma. A benign neoplasm is localized, noninfiltrative, and because it is surrounded by a capsule, easily excisable. A neoplasm of intermediate malignancy is locally infiltrative and difficult to excise but does not metastasize. A malignant neoplasm is infiltrative with metastatic potential. Although cutaneous neoplasms characteristically are nodular or papular, they also can occur as localized or generalized alopecic plaques, erythematous and pigmented patches and plaques, wheals, or nonhealing ulcers. The variability in clinical presentation can make distinguishing a neoplasm from an inflammatory disease difficult; furthermore, distinguishing a benign tumor from a malignant tumor is even more subjective because sarcomas or carcinomas early in their development may palpate as discrete, encapsulated masses. To establish a definitive diagnosis, histopathology is generally required. Cytologic evaluation can also be useful and, for some neoplasms (eg, round cell tumors), can rival or even surpass the value of histologic examination. Therapy depends largely on the type of tumor, its location and size, and signalment of the animal. For benign neoplasms associated with neither ulceration nor clinical dysfunction, no therapy may be the most prudent option, especially in aged dogs. For more aggressive neoplastic diseases or benign tumors that inhibit normal function or are cosmetically unpleasant, there are several therapeutic options. For most, surgical intervention with complete excision provides the best chance of a cure at least cost and often with the fewest side effects. Lumpectomy is adequate for benign lesions, but if a malignancy is suspected, the lesion should be removed with wide (3 cm) surgical margins. For tumors that cannot be completely excised, partial removal or debulking may prolong the life of the animal and increase the effectiveness of radiation or chemotherapy. Cryosurgery is also an option, although it is more effective for benign, superficial lesions than for malignant cutaneous neoplasms. Radiation therapy is of most value for infiltrative neoplasms that are not surgically resectable, or when surgical intervention would cause unacceptable physical impairment. Chemotherapy can be used either as a primary method for treatment of malignant neoplasms or as an adjunct to surgery or radiotherapy. In the skin, it is most commonly used to treat round cell tumors (eg, lymphosarcomas, mast cell tumors, transmissible venereal tumors, etc) or solid tumors that cannot be excised completely. Although generally palliative, long remissions may sometimes be obtained. Other forms of therapy include hyperthermia, laser therapy, photodynamic therapy, antiangiogenic therapy, gene therapy, and immunotherapy. ОПУХОЛИ КОЖИ И МЯГКИХ ТКАНЕЙ Опухоли кожи являются наиболее часто диагностируемыми неопластическими заболеваниями у домашних животных, отчасти потому, что их легко выявить, и отчасти потому, что постоянное воздействие внешней среды на кожу предрасполагает этот орган к неопластической трансформации. В развитии кожных новообразований участвуют химические канцерогены, ионизирующее излучение и вирусы, но гормональные и генетические факторы также могут играть определенную роль. Кожа представляет собой сложную структуру, состоящую из различных эпителиальных (эпидермис, аднекса), мезенхимальных (волокнистые соединительные ткани, кровеносные сосуды, жировая ткань), нервных и нейроэктодермальных тканей (периферический нерв, клетки Меркеля, меланоциты), все из которых способны к развитию характерных опухолей. Поскольку опухоли кожи настолько разнообразны, их классификация трудна и часто противоречива. Также существуют разногласия относительно критериев, используемых для определения того, является ли поражение, возникающее в коже или мягких тканях, неопластическим и, если да, то доброкачественным или злокачественным. Чтобы избежать путаницы, в данном обсуждении используются следующие термины: Гамартома (невус) - это локализованный дефект развития, связанный с увеличением одного или нескольких элементов кожи. Например, гамартома сальных желез относится к локализованному участку кожи, где сальные железы чрезвычайно выражены и иногда деформированы. Хотя, по строгому определению, гамартомы присутствуют при рождении, иногда они могут долгое время не достигать размеров, когда они становятся клинически очевидными, и их могут не диагностировать, пока животное не станет взрослым. Чтобы еще больше запутать ситуацию, некоторые поражения с клиническими и гистологическими признаками врожденных гамартом могут развиваться у взрослых животных. Такие "приобретенные" гамартомы трудно отделить от доброкачественных эпителиальных и мезенхимальных новообразований. В медицинской литературе для обычных людей и в некоторых ветеринарных текстах термин "невус" используется как синоним гамартомы. Доброкачественное новообразование локализовано, неинфильтративно и, поскольку окружено капсулой, легко иссекается. Новообразование промежуточной степени злокачественности имеет местную инфильтрацию и трудно поддается иссечению, но не метастазирует. Злокачественное новообразование является инфильтративным с метастатическим потенциалом. Хотя кожные новообразования обычно имеют узелковый или папулезный характер, они также могут проявляться в виде локализованных или генерализованных алопециевых бляшек, эритематозных и пигментированных пятен и бляшек, сыпей или незаживающих язв. Вариабельность клинических проявлений может затруднить отличить новообразование от воспалительного заболевания; кроме того, отличить доброкачественную опухоль от злокачественной еще более сложно, поскольку саркомы или карциномы на ранних стадиях развития могут пальпироваться как дискретные, инкапсулированные образования. Для установления точного диагноза обычно требуется гистопатологическое исследование. Цитологическая оценка также может быть полезной и для некоторых новообразований (например, круглоклеточных опухолей) может соперничать или даже превосходить ценность гистологического исследования. Терапия во многом зависит от типа опухоли, ее расположения и размера, а также от сигнальности животного. При доброкачественных новообразованиях, не сопровождающихся ни изъязвлением, ни клинической дисфункцией, отсутствие терапии может быть наиболее разумным вариантом, особенно у пожилых собак. При более агрессивных неопластических заболеваниях или доброкачественных опухолях, которые препятствуют нормальной функции или косметически неприятны, существует несколько вариантов терапии. В большинстве случаев хирургическое вмешательство с полным иссечением дает наилучшие шансы на излечение при минимальных затратах и часто с наименьшими побочными эффектами. При доброкачественных поражениях достаточно люмпэктомии, но если есть подозрение на злокачественную опухоль, поражение должно быть удалено с широкими (3 см) хирургическими полями. Для опухолей, которые не могут быть полностью удалены, частичное удаление или деструктуризация может продлить жизнь животного и повысить эффективность лучевой или химиотерапии. Криохирургия также является одним из вариантов, хотя она более эффективна при доброкачественных, поверхностных поражениях, чем при злокачественных кожных новообразованиях. Лучевая терапия наиболее эффективна при инфильтративных новообразованиях, не поддающихся хирургической резекции, или когда хирургическое вмешательство может привести к неприемлемым физическим нарушениям. Химиотерапия может использоваться либо как основной метод лечения злокачественных новообразований, либо как дополнение к хирургическому вмешательству или лучевой терапии. На коже она чаще всего используется для лечения круглоклеточных опухолей (например, лимфосаркомы, опухоли тучных клеток, трансмиссивных венерических опухолей и т.д.) или крупных опухолей, которые невозможно полностью иссечь. Несмотря на то, что эта терапия обычно носит паллиативный характер, иногда удается добиться длительной ремиссии. Другие формы терапии включают гипертермию, лазерную терапию, фотодинамическую терапию, антиангиогенную терапию, генную терапию и иммунотерапию. |