2015-10-13
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Ex. 42. Fill the gaps with the words from the list below. Be ready to interpret the text.
Community, tundra biomes, biomes, forest biomes, freshwater biomes, marine biomes, grassland biomes, desert biomes
All the living things together in an ecosystem form a …. For example, a forest community may contain trees, shrubs, wildflowers, squirrels, birds, bats, insects, mushrooms, bacteria, and much more. The different types of communities found on Earth are called …. Six major types of biomes exist:
✓ … include ponds, rivers, streams, lakes, and wetlands. Only about 3 percent of the Earth’s surface is made up of freshwater, but freshwater biomes are home to many different species, including plants, algae, fish, and insects.
✓ … contain saltwater and include the oceans, coral reefs, and estuaries. They cover 75 percent of the Earth’s surface and are very important to the planet’s oxygen and food supply — more than half the photosynthesis that occurs on Earth occurs in the ocean.
✓ … receive minimal amounts of rainfall and cover approximately 20 percent of the Earth’s surface. Plants and animals that live in deserts have special adaptations, such as the ability to store water or only grow during the rainy season, to help them survive in the low-water environment. Some familiar desert inhabitants are cacti, reptiles, birds, camels, rabbits, and dingoes.
✓ … contain many trees or other woody vegetation; cover about 30 percent of the Earth’s surface; and are home to many different plants and animals, including trees, skunks, squirrels, wolves, bears, birds, and wildcats. They’re important for global carbon balance because they pull carbon dioxide out of the atmosphere through the process of photosynthesis.
✓ … are dominated by grasses, but they’re also home to many other species, such as birds, zebras, giraffes, lions, buffaloes, termites, and hyenas. Grasslands cover about 30 percent of the Earth’s surface and are typically flat, have few trees, and possess rich soil. Because of these features, people converted many natural grasslands for agricultural purposes.
✓ … are very cold and have very little liquid water. Tundras cover about 15 percent of the planet’s surface and are found at the poles of the Earth as well as at high elevations. Arctic tundras are home to organisms such as arctic foxes, caribou, and polar bears, whereas mountain tundras are home to mountain goats, elk, and birds. In both types of tundra, nutrients are typically scarce, and the growing seasons are quite short.
Ex. 43. Translate the following text into your native language. Find the synonyms for the words in italics among the terms from the list below.
Autotrophs, herbivores, carnivores, carnivores
One of the most fundamental ways that organisms interact with each other is eating each other. In fact, all the various organisms in an ecosystem can be divided into four categories called trophic levels based on how they get their food:
✓ Producers make their own food. Plants, algae, and green bacteria are all producers that use energy from the Sun to combine carbon dioxide and water and form carbohydrates via photosynthesis.
✓ Primary consumers eat producers. Because producers are mainly plants, primary consumers are also called plant-eating animals.
✓ Secondary consumers eat primary consumers. Because primary consumers are animals, secondary consumers are also called meat-eating animals.
✓ Tertiary consumers eat secondary consumers, so they’re also considered meat-eating animals.
Organisms in the different trophic levels are linked together in a food chain, a sequence of organisms in a community in which each organism feeds on the one below it in the chain. Figure 6 shows a depiction of a simple food chain.
