Coral Reefs: Underwater Cities of Life
Coral Reefs: Underwater Cities of Life
Imagine a bustling city, full of vibrant colors, unique shapes, and a diverse population. Now, picture this city underwater. This is a coral reef! Coral reefs are some of the most fascinating and important ecosystems on our planet. They are often called the "rainforests of the sea" because of the incredible variety of life they support.
What are Corals?
Many people think corals are plants or rocks, but they are actually animals! They are tiny, soft-bodied organisms called polyps. These polyps live in colonies, and over long periods, they secrete a hard, calcium carbonate skeleton. This skeleton forms the structure of the reef. There are two main types of corals: hard corals and soft corals. Hard corals are the reef builders, creating the rigid framework that supports the entire ecosystem. Soft corals, on the other hand, are flexible and often resemble plants or fans, adding to the reef's beautiful, swaying landscape.
A Unique Ecosystem
- Zooxanthellae:
- Algae that live within coral tissues and provide food through photosynthesis.
- Coral Bleaching:
- The process where corals expel zooxanthellae due to stress, causing them to turn white.
- Ocean Acidification:
- The decrease in the pH of the ocean, caused by the uptake of carbon dioxide from the atmosphere.
- polyps:
- Tiny, soft-bodied invertebrate sea animals that live together in colonies to build coral reefs.
- biodiversity:
- The wide variety of different plant and animal species living within a specific habitat or ecosystem.
- symbiotic:
- Describing a close, interdependent relationship between two different living organisms that usually benefits both.
- photosynthesis:
- The biological process by which green plants and algae use sunlight to produce food energy from carbon dioxide and water.
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Preview questions from this passageShowHide
- 1What is a coral reef often called, and why?
- 2What are coral polyps, and what do they secrete?
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About this informational passage for Middle School
“Coral Reefs: Underwater Cities of Life” is a informational reading passage about Coral Reefs, written for Middle School. It takes about 3 minutes to read (499 words) and comes with an interactive quiz and a printable worksheet with comprehension questions and an answer key.