Words with special meanings in articles

Grade 8 Reading Worksheet - Challenge Me

Circle the best answer.

1. Read this first

   The Reef and Its Partners (article)

   [1] Coral reefs cover less than one percent of the ocean floor, yet they shelter roughly a quarter of all marine species, a share far out of proportion to their size. [2] The reef itself is built by coral polyps, tiny animals that secrete hard cups of limestone around their soft bodies and live packed together in colonies. [3] Inside the tissue of each polyp lives a microscopic alga that photosynthesizes, and the two organisms exchange resources in a partnership known as symbiosis. [4] Corals that live in this partnership can thrive in clear tropical water where food is scarce. [5] The alga supplies sugars, while the polyp supplies shelter and the nutrients that the alga needs. [6] The algae also give coral most of its color.

   [7] When the water stays a degree or two above the usual summer temperature for several weeks, the stress breaks the partnership. [8] The polyps expel their algae, the tissue turns transparent, and the white limestone shows through, an event called bleaching. [9] A bleached coral is still alive, but it is starving, and it can recover if cooler water returns soon enough.

   [10] Biologists often call reefs the rainforests of the sea. [11] The phrase reflects the astonishing variety of life on a reef, from sponges and snails to sharks and turtles. [12] After a severe bleaching, the loss of a reef is felt well beyond the water. [13] Fishing families, tourism workers and coastal towns that depend on the shelter of reefs from storm waves all lose something.

2. 1.

   Ari hears a classmate guess that symbiosis means competition between two organisms. Which statement shows the guess is wrong?

   • The alga gives coral most of its color, which shows how the two are related.
   • Each partner supplies something the other needs, so they cooperate.
   • Algae are plants and polyps are animals, so they cannot compete.
   • Both partners need warm, clear water, so they compete for it.
3. 2.

   Bo tests the comparison rainforests of the sea. Which statement shows where it fits the article's facts?

   • Reefs shelter a large share of species while covering a tiny share of the ocean floor.
   • Reefs are mostly green and shaded by a tall canopy.
   • Reefs are built by tiny animals, while rainforests are built by plants.
   • Reefs are stressed when the water stays a degree or two above the usual summer temperature.
4. 3.

   Jun guesses that bleaching means cleaning with chemicals. Which statement shows the guess is wrong?

   • Coral cannot change color.
   • The polyps expel their algae, so color is lost without any cleaning agent.
   • Reefs cover less than one percent of the ocean floor, so cleaning is unlikely.
   • The coral turns white, which matches the result of cleaning with chemicals.
5. 4.

   Kira tests the same comparison again. Which statement shows where rainforests of the sea breaks down?

   • Reefs cover less than one percent of the ocean floor.
   • A reef is built by tiny animals, not by plants as a rainforest is.
   • Reefs hold a great variety of life, as rainforests do.
   • A reef recovers from damage quickly, as a rainforest does.
6. 5.

   Luz reads the list of fishing families, tourism workers and coastal towns at the end. What tone does the list create?

   • Hopeful, as if these groups will soon find other kinds of work.
   • Panic, as if disaster for the whole coast were certain.
   • Neutral, as if the list were just a count of jobs.
   • Concern for people as well as reefs, as the loss spreads.

7. A Slow River of Ice (article)

   [1] A glacier forms where more snow falls in winter than melts in summer, so layer upon layer piles up and compresses into dense ice. [2] Once the ice is thick enough, its own weight makes it creep downhill, and it flows like an extremely slow river. [3] The glacier does not move evenly, because the center flows faster than the edges, where friction with the valley wall holds it back. [4] Where the ice bends over a steep bump, the surface stretches and splits into deep cracks called crevasses. [5] Rocks that the glacier plucks from the valley floor are carried along inside the ice and dumped at its sides and front as a ridge of debris called a moraine.

   [6] At its lower end, the glacier's terminus is the point where the ice melts or breaks off into water. [7] When large blocks fall from a terminus that reaches the sea, the process is called calving. [8] A glacier is said to advance when its terminus moves downhill and to retreat when it moves uphill, though the ice itself keeps flowing forward. [9] Over the past century, most mountain glaciers around the world have retreated, according to repeated surveys of their termini.

   [10] Glaciologists sometimes call a glacier a bank account for water, in which snow is the deposit and melt is the withdrawal. [11] When the withdrawals exceed the deposits for many years, the balance shrinks, and the glacier thins even where its terminus holds still. [12] Surveys use satellites and stakes drilled into the ice to track the balance each year.

8. 6.

   Milo guesses that calving means giving birth. Which statement from the article shows the guess is wrong?

   • The glacier gives birth to icebergs, which matches the guess.
   • Sentence 7 says large blocks fall from a terminus that reaches the sea.
   • Sentence 9 says most mountain glaciers have retreated over the past century.
   • Glaciers are not alive, so they cannot have young.
9. 7.

   Noah tests the bank account comparison. Which statement shows where it fits the article?

   • Years of more melt than snow shrink the balance, like withdrawals beating deposits.
   • A glacier can refill its balance in one season, as an account can with a large deposit.
   • Surveys use satellites and stakes in the ice to track the balance each year.
   • A glacier flows downhill, but a bank account stays in one place.
10. 8.

    Pia reads that a glacier plucks rocks and dumps them at its sides and front. What tone do plucks and dumps give?

    • Threatening, as if the glacier were attacking the valley.
    • Active and forceful, as if the glacier were working on the land.
    • Plain and neutral, since the verbs are just technical terms.
    • Gentle and caring, as if the glacier were tending the rocks.
11. 9.

    Ren guesses that an advancing glacier flows faster than a retreating one. Which statement from the article shows the guess is wrong?

    • Sentence 2 says the ice flows like a slow river, so an advancing glacier flows faster.
    • Sentence 8 says the ice keeps flowing either way, so the words describe the terminus.
    • A glacier cannot move forward, so neither word describes flow.
    • Sentence 9 says most mountain glaciers have retreated, so retreating glaciers flow slowly.
12. 10.

    Zee reads that withdrawals exceed the deposits and the balance shrinks. What tone do these money terms give the last paragraph?

    • Urgent, as if the glacier would vanish this year.
    • Neutral, as if the passage had no point of view.
    • Measured, since the terms make a slow loss easy to follow.
    • Reassuring, as if shrinking were a normal and harmless matter.