trichocyst

Description:

The body of the trichocyst is composed of a core and a cortex which have slightly different electron diffracting properties, thus the cortex is darker since it scatters more electrons. An electron transparent zone surrounds the cortex and separates the trichocyst membrane from the body. The trichocyst tip is composed of a central spike covered by a sheath. The spike is nail-shaped with its head resting on the trichocyst body. The trichocyst membrane completely surrounds both trichocyst body and sheath. (Details of trichocyst fine structure were recorded by Bannister, J. Cell Sci. 11:899-929, 1972.) EM taken on 4/6/78 by R. Allen with Hitachi HU11A TEM. Neg. 14,750X. Bar = 0.5 micron. This image is available in Richard Allen's collection.