Which reason best explains why dead specimens must be used with transmission electron microscopes? electrons pass over the specimen. the lights that are used are harmful to the specimens. specimens are placed in a vacuum. the image that is produced is two dimensional.

The answer is: Specimens are placed in a vacuum.

An electronic microscope is used for visualization of biological samples, which must be prepared before visualization. Vacuum is present inside the electronic microscope. It is very important and without it, electrons will hit air particles instead of the specimen. Water, abundant in the specimens, will, thus, evaporate and the specimen will anyhow be dead.

Ifound this information on google “yes. they have a mouth and brain at one end and an anus at the opposite end. what characteristics distinguish an annelid from other worms? annelids have segmented bodies and a coelem which is a tube filled with fluid and contains most of the organs.“ i hope it you