Question: list the structures of the nephron where filtration occurs
[{'answer': 'endothelial cells', 'provenance': [{'wikipedia_id': '215248', 'title': 'Nephron', 'start_paragraph_id': 1, 'start_character': 545, 'end_paragraph_id': 1, 'end_character': 562, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'between the foot processes of the podocytes of the lining of the capsule'}, {'answer': 'the endothelial cells of the capillary wall'}, {'provenance': [{'wikipedia_id': '215248', 'title': 'Nephron', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 1384, 'bleu_score': 0.9911697618108691, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 3824541097077396600}, 'section': 'Section::::Abstract.'}]}]