Glossary: Allergy vocabulary

Allergy

al·ler·gy Pronunciation (lr-j)
n. pl. al·ler·gies
1. An abnormally high sensitivity to certain substances, such as pollens, foods, or microorganisms. Common indications of allergy may include sneezing, itching, and skin rashes.
2. Informal An adverse sentiment; antipathy: an allergy to cocktail parties.

An allergy can refer to several kinds of immune reactions including Type I hypersensitivity in which a person's body is hypersensitised and develops IgE type antibodies to typical proteins. When a person is hypersensitised, these substances are known as allergens. The word allergy derives from the Greek words allos meaning "other" and ergon meaning "work". Type I hypersensitivity is characterised by excessive activation of mast cells and basophils by immunoglobulin E resulting in a systemic inflammatory response that can result in symptoms as benign as a runny nose, to life-threatening anaphylactic shock and death.

Asteraceae

One of the largest plant families is the composite (also known as the daisy or sunflower family, Compositae or Asteraceae). There are almost 20,000 species contained within this family. The majority of these species are herbs but there are also some shrubs, trees and vines. The family includes many edible sala plants (e.g., lettuce, endive, chicory and artichoke), cultivated species such as the marigolds, daisies, sunflowers and chrysanthenums as well as many common weeds and wildflowers. It is primarily the latter, for example ragweed and mugwort , which are involved in pollen-induced seasonal allergies

Cat Allergy

One of the most common animal allergies. It is caused by a tiny protein particle, the Fel d 1 allergen, which is found in the cat's skin flakes and saliva.

Ragweed

Ragweed (Ambrosia) refers to the group of aproximately 15 species of weed plants, belonging to the Compositae family. Most ragweed species are native to North America, althought they are also found in Eastern Europe and the French Rhône valley. The ragweeds are annuals characterised by their rough, hairy stems and mostly lobed or divided leaves. The ragweed flowers are greenish and inconspicuously concealed in small heads on the leaves. The ragweed species, whose copious pollen is the main cause of seasonal allergic rhinitis (hayfever) in eastern and middle North America, are the common ragweed ( A. artemisiifolia ) and the great, or giant, ragweed ( A. trifida ). The common ragweed grows to about 1m (3.5 feet), is common all across North America and is also commonly refered to as Roman wormwood, hogweed, hogbrake or bitterweed. The giant ragweed, meanwhile, can reach anywhere up to 5 m (17 feet) in height and is native from Quebec to British Columbia in Canada and southward to Florida, Arkansas, and California in the USA. Due to the fact that ragweeds are annuals, they can be eradicated by being simply mowed before they release their pollen in late Summer.