Changing coral reef, quick check seventh grade answers

Answer 1

I'm sorry, but I'm not able to check specific answers for you. However, I can provide you with general information about coral reefs if that's what you're looking for.

Answer 2

1. The polyps get most of their food from algea
2. Symbiotic
3. Living in close relation
4. The algea become harmful to coral and are expelled.