(a) Innate, or non-specific, immunity is the defense system with which you were born. It protects you against all antigens. Innate immunity involves barriers that keep harmful materials from entering your body. These barriers form the first line of defense in the immune response.
(b) Allergy occurs when a person reacts to substances in the environment that are harmless to most people. These substances are known as allergens and are found in dust mites, pets, pollen, insects, ticks, moulds, foods and some medications. Atopy is the genetic tendency to develop allergic diseases.
(c) A carcinogen is any substance, radionuclide, or radiation that promotes carcinogenesis, the formation of cancer. This may be due to the ability to damage the genome or to the disruption of cellular metabolic processes.
(d) Abnormal physical or psychological features that follow the abrupt discontinuation of a drug that has the capability of producing physical dependence. In example, common opiates withdrawal symptoms include sweating, goosebumps, vomiting, anxiety, insomnia, and muscle pain.
(e) Endoparasites are parasites that live in the tissues and organs of their hosts, such as tapeworms, flukes, and protozoans of vertebrates.