There are different materials of raw water, but also the raw water comes from ponds,rivers, and oceans but they might be good sometimes, and gas not been treated and has bacteria or mold buy that is not good.
Answer:
Exocytosis
Explanation:
Exocytosis is a type of active transport in which the cell membrane fuses with secretory vesicles and expels their content (water-soluble molecules, hormones, neurotransmitters, etc.) into the extracellular space. Exocytosis can be regulated or constitutive. Regulated exocytosis occurs in response of a specific signal while constitutive exocytosis secretes molecules without the need of a signal. Ca2+ is an external signal that triggers regulated exocytosis which is particularly important in neuron synapses.