#alveolar_bed  lung tissue densely packed with alveoli
  supertype:  anatomical_structure__structure__complex_body_part__bodily_structure__body_structure  a particular complex anatomical structure; "he has good bone structure"
  part of:  lung  either of two saclike respiratory organs in the chest of vertebrates; serves to remove carbon dioxide and provide oxygen to the blood
     part of:  lower_respiratory_tract__lowerrespiratorytract  the bronchi and lungs

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