Final answer:
According to Egyptian myth, the heart was left out of the Canopic jars so it could be weighed during the judgment in the afterlife.
Step-by-step explanation:
The Canopic jars were used in ancient Egypt to store the organs of the deceased during the mummification process. The four Canopic jars represented the four sons of the god Horus and each jar was associated with a specific organ.
The organ that was left out of the Canopic jars and not preserved was the heart. In Egyptian belief, it was believed that the heart was the center of a person's being and contained their emotions and intellect. Instead of being preserved, the heart was left in the body during mummification and later weighed against the feather of Ma'at during the judgment in the afterlife.
Learn more about Egyptian myth and mummification