The document summarizes the human body systems including stimuli and responses, the nervous system, skeletal system, and musculature. It describes how stimuli can originate internally or externally and be received by receptors, with responses being muscular or glandular. It outlines the central and peripheral nervous systems, including neurons, and how voluntary and involuntary movements are controlled. Finally, it provides an overview of the skeletal system including different bone groups, joints, and muscles in the head, trunk, and limbs.