Final answer:
The gastrointestinal tract is the portal of entry for pathogens contained in ingested substances.
Step-by-step explanation:
The statement is true. The gastrointestinal tract is indeed the portal of entry for pathogens contained in ingested substances. The GI tract consists of the mouth, pharynx, esophagus, stomach, small intestine, and large intestine. When we ingest food or drink, any pathogens present in those substances can enter our body through this route. For example, if food is contaminated with bacteria like Salmonella or E. coli, these pathogens can enter the GI tract and cause infections.