• Audience
    Primary school
  • Learning stage
    Stage 2, Stage 3, Stage 4
  • Learning area
    Climate change, Science
  • Type
    Learning resources

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Corals are invertebrates that live in the ocean, and are relatives of anemones and jellyfish. They form colonies that are made up of identical 'polyps', which can create a hard skeleton to attach to. Polyps are cylinder-shaped animals that connect to the skeleton at their base and have a circle of tentacles at their mouth opening. Polyps can create large skeletons which in turn make up the ecosystems called coral reefs.

While some corals can catch and eat fish or plankton, most corals get their energy from the zooxanthellae that live inside their tissues. Zooxanthellae can photosynthesize (just like plants), converting sunlight into energy! They also give coral their bright and beautiful colours.

But what causes corals to lose their colour, get sick and die in the process called 'coral bleaching'? Watch Zara's video below to find out.




About the video

Big Problem: Coral Bleaching is an entertaining investigation into one of the most widespread issues affecting coral reefs. Inspired by her passion for the ocean, Zara sets out to educate viewers on some of the main causes of coral bleaching, the scientific process behind it and ways that everyone can work together to help minimise the issue.



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