Question: where does electron transport system occur in mitochondria
[{'answer': 'At the mitochondrial inner membrane', 'provenance': [{'wikipedia_id': '92236', 'title': 'Electron transport chain', 'start_paragraph_id': 9, 'start_character': 147, 'end_paragraph_id': 9, 'end_character': 182, 'bleu_score': 1.0, 'section': 'Section::::In mitochondria.\n'}]}, {'provenance': [{'wikipedia_id': '92236', 'title': 'Electron transport chain', 'start_paragraph_id': 9, 'start_character': 0, 'end_paragraph_id': 9, 'end_character': 1085, 'bleu_score': 0.9877670085238551, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 16198783968260884350}, 'section': 'Section::::In mitochondria.\n'}]}]