Sym­bio­sis and Sus­tain­abil­ity in Corals by An­to­nia Dar­ragh — One-on-one re­la­tion­ships are fre­quent in coral reefs. Most corals house pho­to­syn­thetic al­gae, for ex­am­ple, in sym­bi­otic re­la­tion­ships that al­low for in­ti­mate and cyclic ex­change of sus­tain­ing com­pounds in a nu­tri­ent-poor en­vi­ron­ment. The coral ben­e­fits from the prod­ucts of the algae's pho­to­syn­the­sis, such as sug­ars, while the al­gae...