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flower

(Encyclopedia)CE5 Longitudinal cross section of a flower at the time of fertilization, showing a pollen grain and a pollen tube. flower, name for the specialized part of a plant containing the reproductive orga...

blood bank

(Encyclopedia)blood bank, site or mobile unit for collecting, processing, typing, and storing whole blood, blood plasma and other blood constituents. Most hospitals maintain their own blood reserves, and the Americ...

hemolysis

(Encyclopedia)hemolysis hĭmŏlˈĭsĭs [key], destruction of red blood cells in the bloodstream. Although new red blood cells, or erythrocytes, are continuously created and old ones destroyed, an excessive rate of...

neoplasm

(Encyclopedia)neoplasm or tumor, tissue composed of cells that grow in an abnormal way. Normal tissue is growth-limited, i.e., cell reproduction is equal to cell death. Feedback controls limit cell division after a...

blood count

(Encyclopedia)blood count, method for determining the number of red (erythrocytes) and white (leukocytes) blood cells in a certain volume of blood. This test can be used as a preliminary step in diagnosing some dis...

pancreas

(Encyclopedia)pancreas pănˈkrēəs [key], glandular organ that secretes digestive enzymes and hormones. In humans, the pancreas is a yellowish organ about 7 in. (17.8 cm) long and 1.5 in. (3.8 cm) wide. It lies b...

respiration

(Encyclopedia)CE5 Respiratory system respiration, process by which an organism exchanges gases with its environment. The term now refers to the overall process by which oxygen is abstracted from air and is tran...

inflammation

(Encyclopedia)inflammation, reaction of the body to injury or to infectious, allergic, or chemical irritation. The symptoms are redness, swelling, heat, and pain resulting from dilation of the blood vessels in the ...

Allison, James Patrick

(Encyclopedia)Allison, James Patrick, 1948–, American immunologist, b. Alice, Tex., Ph.D. Univ. of Texas, Austin, 1973. Allison was a researcher at the Univ. of Texas System Cancer Center in Houston from 1977 to ...

Gram's stain

(Encyclopedia)Gram's stain, laboratory staining technique that distinguishes between two groups of bacteria by the identification of differences in the structure of their cell walls. The Gram stain, named after its...