Which marine ecosystem has the greatest biodiversity? a. coral reef b. mangrove swamp c. open ocean d. salt marsh?

Hector is back from his morning run and is feeling light-headed because his energy is depleted which food item will provide him with a quick source of carbohydrates

Isolated volcanic peaks on the ocean floor are

Which kind of worm has a closed circulatory system? a planarian b fluke c pinworm d an earthworm