title: Muscularis submucosae ani and its development.
mesh_terms: D000328:Adult; D001003:Anal Canal / Q000033:anatomy & histology / Q000196:embryology / Q000254:growth & development*; D002648:Child; D002675:Child, Preschool; D003094:Collagen / Q000032:analysis; D004547:Elastic Tissue / Q000033:anatomy & histology; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007413:Intestinal Mucosa / Q000033:anatomy & histology*; D024510:Muscle Development; D009132:Muscles / Q000196:embryology; D012007:Rectum / Q000033:anatomy & histology
chemical_list: D003094:Collagen