Definition. A fibroblast is a cell that manufactures and maintains connective tissue, the structural framework that supports the organs of all animals. Fibroblasts secrete fibrous proteins and ground substance, which together form the extracellular matrix that is the basis of connective tissue. fibroblast is a cell that manufactures and maintains connective tissue, the structural framework that supports the organs of all animals.
Therefore, there is very little chlorophyll in these tropical waters, keeping them clear. (As an aside, corals are symbioses where phytoplankton have evolved to survive in nutrient-poor tropical waters by living inside the bodies of the corals and obtaining nutrients directly from the waste products of the corals.
The other cause for turbidity is living organic material in the water; it is also an important reason that California water is less clear than Hawaiian or Bahamian waters. The waters off California typically have much more phytoplankton and chlorophyll, and therefore are more turbid, than in Hawaii or the Bahamas.