In most animals, the gut or digestive tract can be thought of as:

The gut or the digestive tract in most animals can be thought of as the tube that runs from the animal’s mouth to its anus. Hence, this tube transfers food to the organs of digestion. Moreover, this organ system takes in food, digests it to extract and absorb energy and nutrients and expels the remiaining waster as solid waste that is release from the body. 

other information encoded in your genes might distinguish you from the others in the group