Which bone classification includes the femur and humerus?

A. Skeletal muscle: Skeletal muscle is attached to bones and controlled voluntarily through the somatic nervous system. It enables walking, lifting, posture, and other conscious movements.

B. Cardiac muscle: Found only in the heart; it is involuntary and controlled by autonomic and intrinsic conduction systems.

C. Smooth muscle: Involuntary muscle found in the GI tract, blood vessels, and bronchi. It controls peristalsis, vasoconstriction, and other automatic functions.

D. Nervous tissue: Not a type of muscle. It transmits electrical impulses and is not responsible for movement.

A. Irregular bone; blood cell production:Irregular bones have complex shapes (e.g., vertebrae, facial bones). While they do contain marrow for blood cell production, the bones of the leg are not classified as irregular.

B. Flat bone; mineral storage:Flat bones (e.g., sternum, skull, ribs) protect internal organs and provide attachment points for muscles. They are not the primary classification for limb bones.

C. Long bone; support and leverage:The bones of the legs (femur, tibia, fibula) are classified as long bones because they are longer than they are wide. Their structure (a long shaft with expanded ends) is mechanically engineered to support body weight and act as levers to facilitate movement when muscles contract.

D. Short bone; protection:Short bones are roughly cube-shaped (e.g., carpals in the wrist, tarsals in the ankle). Their primary function is stability and some motion, rather than the leverage provided by long bones.