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tea
(Encyclopedia)tea, tree or bush, its leaves, and the beverage made from these leaves. The plant (Camellia sinensis, Thea sinensis, or C. thea) is an evergreen related to the camellia and indigenous to Assam (India)...maté
(Encyclopedia)maté yĕrˈbä, –bə [key], or Paraguay tea, evergreen tree (Ilex paraguariensis) of the family Aquifoliaceae (holly family). From ancient times Native Americans and now millions of Argentines and ...beta-blocker
(Encyclopedia)beta-blocker or beta-adrenergic blocking agent bāˈtə ădˌrənûrˈjĭk [key], drug that reduces the symptoms connected with hypertension, cardiac arrhythmias, angina pectoris, migraine headaches, ...neurotransmitter
(Encyclopedia)neurotransmitter, chemical that transmits information across the junction (synapse) that separates one nerve cell (neuron) from another nerve cell or a muscle. Neurotransmitters are stored in the nerv...drug addiction and drug abuse
(Encyclopedia)drug addiction and drug abuse, chronic or habitual use of any chemical substance to alter states of body or mind for other than medically warranted purposes. Traditional definitions of addiction, with...arrhythmia
(Encyclopedia)arrhythmia ārĭᵺˈmēə [key], disturbance in the rate or rhythm of the heartbeat. Various arrhythmias can be symptoms of serious heart disorders; however, they are usually of no medical significan...nervous system
(Encyclopedia)CE5 Nerve cell CE5 Nervous system nervous system, network of specialized tissue that controls actions and reactions of the body and its adjustment to the environment. Virtually all members of ...marijuana
(Encyclopedia)marijuana or marihuana, drug obtained from the flowering tops, stems, and leaves of the hemp plant, Cannabis sativa (see hemp) or C. indica; the latter species can withstand colder climates. It is one...Browse by Subject
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