Question: what did the electron microscope allow scientists to see
[{'answer': 'the ultrastructure', 'provenance': [{'wikipedia_id': '9730', 'title': 'Electron microscope', 'start_paragraph_id': 3, 'start_character': 45, 'end_paragraph_id': 3, 'end_character': 63, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '9730', 'title': 'Electron microscope', 'start_paragraph_id': 3, 'start_character': 0, 'end_paragraph_id': 3, 'end_character': 422, 'bleu_score': 0.9468812661363221, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 3101231574011129063}, 'section': 'Section::::Abstract.'}]}]