The diaphragm is a large, dome-shaped striated muscle with a non-muscular part, attaching to the lower six ribs, the xiphoid process, and vertebrae L1-L2.

“it's a dome-shaped muscle it's a striated muscle but it has kind of a a non-muscular part as well but i think what most people don't appreciate is how big it is right yeah and how i can't even remember it's been you know back when i was you know in school i had to know every attachment of it but it um do you recall how far it attaches down and up on the on both the the ribs and the vertebral bodies yeah so the diaphragm just think of it like a big parachute or a big sheath of muscle that separates the abdominal cavity from the the heart and lungs the attachments it has attachments on the lower six ribs on the back of the xiphoid process which is a little bone at the end of the sternum and then also attachments on uh l1 l2 uh vertebra so that's right around the thoracic lumbar junction”