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plant

(Encyclopedia)plant, any organism of the plant kingdom, as opposed to one of the animal kingdom or of the kingdoms Fungi, Protista, or Monera in the five-kingdom system of classification. (A more recent system, sug...

Nägeli, Karl Wilhelm von

(Encyclopedia)Nägeli or Naegeli, Karl Wilhelm von both: kärl vĭlˈhĕlm fən nāˈgəlē [key], 1817–91, Swiss botanist. He was professor at the Univ. of Munich from 1858 and was noted especially for his work ...

viroid

(Encyclopedia)viroid, microscopic infectious agent, much smaller than a virus, that infects higher plants such as potatoes, tomatoes, chrysanthemums, and cucumbers, causing stunted or distorted growth and sometimes...

isogamy

(Encyclopedia)isogamy īsŏgˈəmē [key], in biology, a condition in which the sexual cells, or gametes, are of the same form and size and are usually indistinguishable from each other. Many algae and some fungi h...

Brown, Michael Stuart

(Encyclopedia)Brown, Michael Stuart, 1941–, American molecular geneticist, b. New York City, M.D. Univ. of Pennsylvania, 1966. He worked (1968–71) as a researcher at the National Institutes of Health before goi...

Weissman, Drew

(Encyclopedia)Weissman, Drew 1959–, b. Lexington, Mass., American Immunologist, studied at Brandeis University (B.A., M.A., 1981) and Boston University (M.D, Ph.D.,...

bacteriophage

(Encyclopedia)bacteriophage băktērˈēəfājˌ [key], virus that infects bacteria and sometimes destroys them by lysis, or dissolution of the cell. Bacteriophages, or phages, have a head composed of protein, an i...

cellular telephone

(Encyclopedia)cellular telephone or cellular radio, telecommunications system in which a portable or mobile radio transmitter and receiver, or “cellphone,” is linked via microwave radio frequencies to base tran...

anchor

(Encyclopedia)anchor, device cast overboard to secure a ship, boat, or other floating object by means of weight, friction, or hooks called flukes. In ancient times an anchor was often merely a large stone, a bag or...

Varna

(Encyclopedia)Varna värˈnä [key], city (1993 pop. 307,200), E Bulgaria, on the Black Sea. It is a major port and an industrial center. Manufactures include ships and boats, chemicals, electrical equipment, and t...