The inactivation of an X chromosome. One of the two X chromosomes in every cell in a female is randomly inactivated early in embryonic development. Named after geneticist Mary Lyon.
A process by which material is rapidly frozen and dehydrated under high vacuum.
To freeze-dry. The material is rapidly frozen and dehydrated under high vacuum. The process is termed lyophilization.
A theory put forth by a Russian plant-breeder named Trofim Denisovich Lysenko [1898-1976] during the Lenin/Stalin years that served to stifle the progress of genetics in the Soviet Union. Lysenko rejected Mendelian genetics in favor of the doctrine of acquired characteristics, a form of Lamarckism. (According to the earlier doctrine of Lamarck, evolution occurs because […]
The theory of acquired characteristics put forth by Jean-Baptiste P.A. Lamarck (1744-1829), a French botanist, zoologist and biological philosopher. According to Lamarck, evolution occurs because organisms can inherit traits acquired by their ancestors. Giraffes can only survive by eating leaves high up on trees so they stretch their necks to reach the leaves and this […]
Destruction. Hemolysis is the destruction of red blood cells with the release of hemoglobin; bacteriolysis is the destruction of bacteria; etc. Lysis can also refer to the subsidence of one or more symptoms of an acute disease as, for example, the lysis of fever in pneumonia.