【正确答案】 Technologically, chemical and biological weapons are almost entirely different. Chemical weapons are highly toxic poisonous, manufactured substances that can be disseminated as vapors, aerosols, or liquids. Biological weapons, on the other hand, are living, disease-causing microorganisms or toxins which, in their most effective form, are disseminated as aerosols that are inhaled. Chemical weapons require a dissemination system, such as a sprayer or explosive device. Once released against an unprotected population, chemical weapons tend to function quickly and can produce noticeable symptoms within an affected group in a matter of seconds or minutes. Most chemical weapons have a distinctive odor and can be seen in the atmosphere. Exposure to a chemical warfare agent is not necessarily fatal, since the effects of chemical weapons depend on a wide range of factors , including dose, the length of time a person is exposed, the level of protection a person has, and whether medical treatment is available.