Question: where are tight junctions found in the human body
[{'answer': 'vertebrates', 'provenance': [{'wikipedia_id': '2022381', 'title': 'Tight junction', 'start_paragraph_id': 1, 'start_character': 407, 'end_paragraph_id': 1, 'end_character': 418, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]