Outline the three mechanisms by which corals obtain their nutrition

Question

What will be an ideal response?

Answer 1

The corals have three known mechanisms to obtain nutrition: filter-feeding, glucose from symbiotic zooxanthella, and harvesting bacteria biomass. Not all the corals utilize all three methods but rely on the modes in various combinations. Filter-feeding supplies only about 5-10% of their nutritional needs; the balance is derived from their symbiotic relationships with the dinoflagellates and bacteria. The bacteria are able to utilize dissolved organic matter (DOM) obtained from the water and coral. The corals also can absorb DOM and suspended organic matter directly across the body surface. Finally, mesenteric filaments can be extruded from the mouth and used to absorb and digest food particles outside the body.