Final answer:
Rebound tenderness and guarding are two peritoneal signs in the abdomen exam.
Step-by-step explanation:
Two 'peritoneal signs' in the abdomen exam are rebound tenderness and guarding.
Rebound tenderness is a sign of peritonitis, which is inflammation of the peritoneum. It is characterized by pain that increases when pressure is released.
Guarding refers to the involuntary contraction of the abdominal muscles in response to pain or inflammation. It is a protective mechanism to minimize movement and further injury to the abdomen.