A coral reef is a complex [ecosystem] of calcium carbonate shells that are home to microbes, algae, invertebrates, and fishes, and its high productivity helps provide great species richness.
Answer:
Orbit or Orbitals, they orbit around the sun counter-clockwise
Fun Fact:
If you looked at the solar system from the bottom the planets would move clockwise.
D) Hypotonic
Aka when skin cells swell from excess water
