Decomposition and putrefaction of the body due to bacterial action takes place.

The bacteria ever present in the alimentary canal make their way from this into the dead tissue.
Certain of these bacteria produce gas which accumulates in the tissues and the body often swells enormously.

A greenish discoloration appears, which is due to the union of the products of decomposition with the iron in the blood; this is more prominent over the abdomen and appears in lines along the course of the veins.

The rapidity with which decomposition takes place varies, and is dependent upon many factors, such as the surrounding temperature, the nutrition of the body at the time of death, the cause of death.

It is usually not difficult to recognize that a body is dead.