Final answer:
The organ that outpockets from the cecum is the appendix.
Step-by-step explanation:
The organ that is a worm-like sac that outpockets from the cecum is called the appendix. It is a winding tube that attaches to the cecum, which is the first part of the large intestine. Although the appendix is generally considered vestigial, recent studies suggest that it may serve as a bacterial reservoir during diarrheal illness.