Untreated waste must be carried on board until it can be properly empty at a pump out station or IN AN APPROVED SEWAGE TREATMENT WORKS. On Ohio waters, it is a law that no vessel should discharge untreated waste into the waters. Such wastes should be drained into reservoirs that can be carried or pumped ashore for disposal.<span />
DDT is biologically magnified and concentrated as it moves through the food web. This increase in concentration is due to Metabolism of DDT which excretes more slowly than the nutrients which moves from one trophic level to next. so DDT accumulates in the body especially in the Fats.
The structure of DNA is double helix which looks like twisted ladder. The sides of the DNA molecule, the rails of the ladder are composed of alternate phosphate and sugar molecules.