Question: where is the blood first filtered in a nephron
[{'answer': 'glomerulus', 'provenance': [{'wikipedia_id': '215248', 'title': 'Nephron', 'start_paragraph_id': 1, 'start_character': 244, 'end_paragraph_id': 1, 'end_character': 254, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '215248', 'title': 'Nephron', 'start_paragraph_id': 3, 'start_character': 0, 'end_paragraph_id': 3, 'end_character': 1717, 'bleu_score': 0.9920790520013891, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 5523346245189875752}, 'section': 'Section::::Abstract.'}]}]