What best describes the function of the endoskeleton in vertebrates?

The function of the endoskeleton in vertebrates is best described as supporting surrounding soft tissues. The endoskeleton, which is made up of bones and cartilage, serves as a structural framework that maintains the body's shape and supports the weight of the organism. This support allows for organ protection, the attachment of muscles, and the overall structural integrity necessary for various physiological processes.

While the endoskeleton certainly plays a role in facilitating movement through muscle attachment, supporting soft tissues encompasses the broader context of providing structural support and maintaining overall body organization. This foundational role is critical for allowing vertebrates to withstand gravity and accommodate the forces exerted by muscles during movement, ultimately enabling a wide range of activities.

In terms of protecting against external damage, although the endoskeleton does provide some protective function for internal organs, such as the ribcage protecting the heart and lungs, its primary role is still more focused on structural support rather than direct protection. Additionally, metabolic energy generation is not a function of the endoskeleton; rather, energy metabolism occurs in many other systems within the body.