Primitive and Advanced Termite Species
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Paragraph 1：Termites are insects that collect vegetation, chew it up, and leave the chemical breakdown to other organisms. There are two strategies. The most primitive termites swallow the chewed vegetation and pass it to a fermentation chamber in their bodies. There, anaerobic bacteria break down the cellulose, an organic compound that forms about 33 percent of all plant matter. The termites are nourished by the ever-growing population of microorganisms in their guts that turn the grass, leaves, and twigs the insects ingest into glucose. Cattle do much the same thing: they allow bacteria to ferment the cellulose in an airtight rumen (digestive chamber), and then digest the bacteria.
1. According to paragraph 1, in what way are the most primitive termites like cattle？
O They have two ways of breaking down the cellulose in vegetation.
O They get no nutritional benefit from eating vegetation.
O Their digestive chambers are not airtight.
O They rely on bacteria to process the vegetation they ingest.
Paragraph 2：Termite evolution has several obvious trends, from primitive species, which live in small hidden colonies, to groups millions strong, the builders of enormous mounds that allow for heat and gas exchange. The less advanced groups digest microorganisms, which do the real work of breaking food down. The culture (colony) of cellulose digesters is passed along through a special exchange. Young termites feed on a special liquid secretion provided by adults, rich in the group’s digestive heritage. When reproductive termites, those destined to produce offspring, leave the nest, they carry in their stomachs the microorganisms essential for the digestive success of their offspring. Treat a colony of these termites with an antibiotic solution, and they will slowly starve to death.
2. The phrase special exchange in the passage refers to
O the transfer of cellulose digesters from one colony of termites to another
O the development of small colonies into much larger ones
O the transfer of liquid secretions from adult termites to young termites
O the departure of certain reproductive termites and the arrival of others
3. Why does the author include the statement “Treat a colony of these termites with an antibiotic solution, and they will slowly starve to death”?
O To suggest one reason why termites sometimes leave a colony
O To emphasize how dependent the termites are on bacteria
O To account for the elimination of certain termite lineages
O To help explain why termites protect essential microorganisms by carrying them in their stomachs
Paragraph 3：More advanced species have a different feeding strategy. The energy source is still cellulose, but it is digested outside the termite’s body. Not having to carry around large chambers of slowly fermenting cellulose solution makes these species more nimble and efficient. Foragers bring twigs and leaves back to special areas and chew them. They then transplant bits of fungus growing on other pieces of nearby vegetation onto the gnawed edges, where the fungi break down the cellulose. Fungi is the only kingdom of organisms able to digest cellulose in air, though they need warmth and humidity to do the job efficiently. This is just what the termites provide. Moreover, these social insects carefully tend the fungus-covered vegetation by treating it with antibiotics they secrete to keep bacterial growth to a minimum. When it is time for the fungus to reproduce, pieces are carried into the open to complete the life cycle. Some species of fungi are found only in termite mounds of a particular species; without their caretakers, these fungi would die. Needless to say, the termites eat the fungi; neither can live without the other. Reproductive termites even carry a chunk of fungi when they leave on mating flights.
4. According to paragraph 3, each of the following is true about the fungi found in termite nests EXCEPT:
O The fungi can digest cellulose in the presence of air.
O The fungi secrete antibiotics to keep bacterial growth to a minimum.
O The fungi reproduce in the open with the help of termites.
O The fungi need a warm, humid environment to function effectively.
Paragraph 4：The evolutionary trend in termites is to forsake excavated nests in soil or wood, like those of most ants, for carton nests constructed inside excavations or on trees. (When referring to termites, carton means, broadly, nesting material consisting of a mix of adhesive saliva or feces with earth or pulp, and even sand, to create cells, floors, walls, graceful arches, tiered roofs, chimney stacks, and buttressed towers up to twenty feet high.) Primitive termites do not store food; they live from hand to mouth, inside a rotting tree, for instance. Advanced termites have special carton areas for food they hold in reserve; these supplies consist of nonperishable material such as grass clippings, analogous to the hay and straw fed to cattle in the winter, and are kept in a dry carton loft. Primitive species need wet cellulose, such as damp wood; more advanced species can also process dry material.
5. Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information.
O In winter, when fresh grass is not available, termites must rely on nonperishable food sources such as hay and straw.
O Advanced termites store different foods in different chambers, reserving the least perishable material for winter.
O Advanced termites have special chambers where they store nonperishable food supplies.
O Advanced termites’ supplies of grass clippings are like hay and straw fed to cattle in winter.
6. Paragraph 4 suggests that for primitive termites, a major advantage of nesting inside a rotting tree is that a rotting tree
O is a very easy site to excavate
O provides a ready source of wet cellulose
O provides a lot of raw material for making carton
O helps preserve stored food
Paragraph 5：To expand their niche in this way, dry-diet termites require a source of water. In arid habitats, they excavate vertical tunnels down to the water table, as much as 150 feet below, which fan out at the base to increase the area of contact and thus maximize the rate of subsurface water accumulation. Finally, less advanced termites remain their entire lives in tunnels and cells excavated in or near wood. More complex species, on the other hand, search for food away from a central nest. To ensure that they can work in safety, they burrow shallowly through the earth or build mud-covered tunnels on the surface of the ground or trees and around the food they wish to harvest.
7. According to paragraph 5, which of the following is true about the vertical tunnels constructed by dry-diet termites？
O They allow water from the surface to accumulate underground.
O They are generally wider at the top than at the bottom.
O They provide extra space so that dry-diet termite populations can expand.
O They are constructed to provide direct access to water.
8. According to paragraph 5, why do termites build mud-covered tunnels on the surface of the ground？
O To make harvesting food less dangerous
O To create a safe place to live
O To avoid contact with surface water
O To avoid competition with species that create deep underground tunnels
Paragraph 1：Termites are insects that collect vegetation, chew it up, and leave the chemical breakdown to other organisms. ■There are two strategies. The most primitive termites swallow the chewed vegetation and pass it to a fermentation chamber in their bodies. ■There, anaerobic bacteria break down the cellulose, an organic compound that forms about 33 percent of all plant matter. ■The termites are nourished by the ever-growing population of microorganisms in their guts that turn the grass, leaves, and twigs the insects ingest into glucose. ■Cattle do much the same thing: they allow bacteria to ferment the cellulose in an airtight rumen (digestive chamber), and then digest the bacteria.
9. Look at the four squares that indicate where the following sentence could be added to the passage.
This remarkable adaptation, however, is not unique to termites.
Where would the sentence best fit Click on a square to add the sentence to the passage.
10. Directions: An introductory sentence for a brief summary of the passage is provided below. Complete the summary by selected THREE answer choices that express the most important ideas in the passage. Some sentences do not belong in the summary express ideas that are not presented in the passage or are minor ideas in the passage. This question is worth 2 points. Drag your choices to the spaces where they belong. To review the passage, click on View Text.
Primitive Termite Species
O
O
O
Advanced Termite Species
O
O
Answer Choices
O Grow fungi on chewed vegetation
O Do not chew vegetation
O Must remain close to or inside wood
O Are able to digest cellulose in air
O Can consume dry vegetation
O Take care of fungi that break down cellulose
O Have a body chamber specifically for breaking down cellulose
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