Question: which type of gland secretes its product directly into the bloodstream
[{'answer': 'endocrine glands', 'provenance': [{'wikipedia_id': '72672', 'title': 'Exocrine gland', 'start_paragraph_id': 1, 'start_character': 297, 'end_paragraph_id': 1, 'end_character': 313, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '72672', 'title': 'Exocrine gland', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 659, 'bleu_score': 0.979896933041101, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 3229105237283310136}, 'section': 'Section::::Abstract.'}]}]