sentence2_structure: the muscular and skeletal organs<>are known as<>the musculoskeletal system
sentence1: The systems included in the study are the integumentary, skeletal, digestive, circulatory, respiratory, urinogenital, nervous, muscular and endocrine systems as well as sense organs.
sentence2: Together, the muscular and skeletal organs are known as the musculoskeletal system.
question: Together, the muscular and skeletal organs are known as what?