Which postmortem change is caused by gravity pooling of blood?

• A. Algor mortis
• B. Livor mortis
• C. Rigor mortis
• D. Putrefaction

Answer: (B)

Gravity pooling of blood after death is livor mortis, also known as lividity or postmortem hypostasis. Once circulation stops, blood settles by gravity to the lowest parts of the body, producing a distinctive, often purplish discoloration in those dependent areas. This pattern begins within minutes to a few hours and becomes fixed as the vascular system no longer circulates. The fixation is useful because if the body is moved after this process has begun, the new dependent areas may show the discoloration pattern corresponding to the new position, helping investigators infer whether the body was moved after death.

In contrast, algor mortis is the cooling of the body to ambient temperature; rigor mortis is the stiffening of muscles due to ATP depletion; and putrefaction is the decomposition process driven by bacteria.