Musculoskeletal and Integumentary Systems Quiz 1 (p 1-5)

Joint Types and Functionality

• Synchondrosis joints allow bone growth while providing stability and limited mobility.
• Plantar flexion occurs when the foot and toes are bent toward the ground.
• The proximal radioulnar joint rotates the radius medially, allowing it to uncross from the ulna.
• Biaxial joints enable motion in two planes around two axes.
• Ball-and-socket joints feature a ball-like convex surface fitting into a concave socket, allowing for extensive movement.
• Intercarpal joints, found between the two rows of carpal bones in the wrist, are classified as plane joints.

Joint Movement and Stability

• A triaxial joint possesses three degrees of freedom, allowing for movement in all directions.
• The hip joint is responsible for flexion and extension in the sagittal plane, as well as abduction and adduction in the frontal plane.
• The first sternocostal joint is classified as a synovial joint.
• The atlantoaxial joint allows shaking of the head to indicate "no."

Joint Structure and Connectivity

• Syndesmosis joints are directly connected by interosseous connective tissue.
• Diarthrodial joints, or synovial joints, permit the most movement.
• Sutural joints are unique to the skull and provide minimal movement.
• A serrate joint occurs where two bones have overlapping beveled edges.
• The gomphosis joint resembles a peg in a hole, such as a tooth in the mandible.
• Symphyses joints are joined by fibrocartilage in disks or plates.

Joint Capsule and Vascularization

• The outer layer of the joint capsule is poorly innervated but highly vascularized.
• The inner synovial membrane layer is richly innervated but poorly vascularized.

Human Anatomy and Muscle Physiology

• An adult human body contains 206 bones.
• The contraction phase follows the latent phase during a muscle twitch.
• Not all classified joints include synarthroses, diarthroses, and amphiarthroses.
• Isometric contraction occurs when the muscle length remains constant during contraction.
• Troponin binds to calcium ions, initiating muscle contraction.

Muscle Fiber Types and Energy Sources

• Type I muscle fibers are high in oxygen supply and have a slow contraction speed.
• The length-tension relationship describes how muscle tension changes with muscle length.
• Creatine phosphate is not a source of energy for muscle contraction.
• Gravity or friction does not classify as a force involved in the mechanical lever system of the body.
• Parallel muscle fiber arrangement features fibers aligned parallel to the muscle's long axis.
• A motor unit comprises a motor neuron and all muscle fibers it innervates.
• Factors influencing muscle strength exclude variables such as muscle length and contraction velocity.