The nervous system communicates through electrical impulses and the communication is very fast. It works in a relay fashion, from point to point comparable to the way the old telephones systems used to work.
The endocrine system communicates by chemical signals via the bloodstream. Hormones are secreted into the blood and extra cellular fluids, then transported to target cells, which must bear a receptor to be able to bind to a specific hormone, and respond.
Hormones are chemical messengers secreted into blood or extracellular fluid that affect the function of other cells.
Endocrine communication is not quite as fast as the nervous system communication
Coastal Ocean!
Explanation: It’s important to remember that although the ocean produces at least 50 percent of the oxygen on Earth, roughly the same amount is consumed by marine life. Like animals on land, marine animals use oxygen to breathe, and both plants and animals use oxygen for cellular respiration. Oxygen is also consumed when dead plants and animals decay in the ocean.
This is particularly problematic when algal blooms die and the decomposition process uses oxygen faster than it can be replenished. This can create areas of extremely low oxygen concentrations, or hypoxia. These areas are often called dead zones, because the oxygen levels are too low to support most marine life.
NOAA’s National Centers for Coastal Ocean Science conducts extensive research and forecasting on algal blooms and hypoxia to lessen the harm done to the ocean ecosystem and human environment.