Lesson 17.7: Science Connection

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Reef Relief

Since 1984, ten large ships have crashed into the delicate coral reefs that lie off the Florida Keys. Thanks to a new treaty, such crashes may never happen again.

Now, big ships have to steer clear of the coral reefs in a new, protected zone. If they don't, they could face a $100,000 fine.

Coral Cities

Coral reefs look like rocky plants, but they are more like huge underwater cities. The reefs are actually the skeletons of tiny animals called coral polyps. Coral polyps are closely related to sea anemones.

Coral polyps give off calcium carbonate, a mineral which hardens to form skeletons on the outside of their bodies. The skeletons protect their soft bodies.

Colonies of thousands of polyps live together. Over the years, as the polyps die, their skeletons pile up and form a coral reef. Tiny colorful plants and animals, such as lobsters, turtles, and fish, live in and around coral reefs where they find food and shelter.

Rain Forests of the Sea

Coral reefs are not only beautiful, but they are also very important to ocean life. Scientists have called coral reefs “rain forests of the sea” because, like rain forests, a great variety of creatures live in them.

Also like rain forests, coral reefs all over the world are being destroyed. Many different things are harming the reefs.

Pollution and changes in water temperature are killing coral polyps. Careless divers damage reefs by kicking them when they swim by. A single kick can take down the coral-reef equivalent of a whole apartment building!

Giant tanker ships can do even more damage. If a big ship runs into a reef, it can wipe out a reef altogether. Scientists and government officials hope the new treaty will help protect the reefs from at least this one danger.

Word Wise

Something that can be broken easily: Sara makes beautiful, but delicate, jewelry.

An agreement made between two or more governments: Many world leaders signed a treaty to reduce water pollution.

A chemical element that is found in substances such as milk, bones, and shells: Milk is a good source of calcium.

Place that is protected from danger: When a shark appeared, the fish took shelter in an underwater cave.

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Find words related to coral reefs hidden in the Web Word Find puzzle. Words may go up, down, across or on a slant.

Data Hunt

If you visit the National Aquarium in Baltimore, you can see brightly colored fish zoom out of hiding when it's feeding time in the “Atlantic Coral Reef” exhibit. Hundreds of tropical fish, like the spiny porcupine and the striped sergeant major, live in the artificial coral reef contained in a huge, 335,000-gallon tank.

You may use a calculator and a sheet of paper to answer these questions.

  1. The volume of 1 gallon of water is about 231 cubic inches. What is the volume of the 335,000-gallon tank in cubic inches?
  2. Suppose an aquarium tank is 20 feet high and 20 feet wide. If it holds 77,385,000 cubic inches of water, how long is the tank? (HINT: How many cubic inches are in 1 cubic foot?)