In which body part is rigor mortis often first noticed?

• A. Hands
• B. Feet
• C. Jaw
• D. Stomach

Answer: (C)

Rigor mortis is a postmortem change that typically begins to develop in the smaller muscles before it progresses to larger muscle groups. The jaw is one of the areas where rigor mortis is most often first observed due to its smaller musculature. The muscles responsible for the mandible's movement are relatively small compared to those in the extremities, making them more susceptible to the onset of rigor mortis. This phenomenon occurs as the body’s ATP (adenosine triphosphate) supplies are depleted after death, preventing muscle relaxation and causing stiffness.

While rigor mortis can eventually affect multiple parts of the body, it is meaningful to note that the observations regarding the jaw offer valuable information in determining the timing of death. The presence of rigor mortis in the jaw can help professionals in the field understand not only the physiological changes that follow death but also assist in forensic investigations.