题目内容
One of the major reasons the reef is so fascinating to scientists and tourists is its infinite variety. They come in various shapes and sizes, ranging from more than a few thousand meters in area to over one hundred and twenty square kilometers. Some of the very outer reefs are up to expose themselves while others remain fully submerged. The beauty of the reefs can only be truly appreciated from an aerial view.
About two thousand eight hundred species of fish are known to live in the reef region. It could take many years for scientists to come up with a complete list of all the plants and animals found on any one reef. Many species are still to be identified and named, showing a staggering diversity of life.
Coral reefs start out small and grow about half an inch a year. If undisturbed by man, however, they can grow to be quite big. The Great Barrier Reef off the northeast coast of Australia is one good example! Reefs grow best in sunny, shallow, clear water. They rarely grow deeper than forty meters and they prefer salt water. The appropriate temperatures and salinities are most often found in the tropics.
Coral reefs are important because they provide protection and shelter for many different species of fish. Without coral reefs, these fish are left homeless with nowhere to live or to have their babies. Not only do these fish increase the diversity of our world but also reef fish and mollusks feed between thirty and forty million people every year. They also make beautiful pets and the money made by catching and selling these animals provides many people with an income to feed their families.
Coral are also very important in controlling how much carbon dioxide is in the ocean. Without coral, the amount of carbon dioxide in the water would rise drastically and that would affect all living things on Earth.
Lastly, coral reefs are very important because they protect the coasts from strong currents and waves by slowing down the water before it gets to the shore. That is why they are called barrier reefs. They provide a barrier between the ocean and the shore.
1. The vehicles one must take to be able to see the full extent of the reefs might be _______________________.
2. From the passage, write the phrase that means that there are a great variety of plants and animals in the ocean. ____________________________
3. Why do you think reefs require clear and shallow water to grow?
They require clear and shallow water so that __________________________.
4. Explain why the coral reefs are also called barrier reefs.
______________________________________________________________________________.
1.an aeroplane or helicopter
2.The phrase is “showing a staggering diversity of life”
3.sunlight will be able to reach them
4.Because they provide a barrier between the ocean and the shore.
名校课堂系列答案