Division of joints fibrous in nature permitting no movement is

Correct Answer: D

Rationale: Joints that are fibrous and immovable are classified as synarthroses, such as skull sutures, where dense connective tissue binds bones tightly, ensuring stability with no motion. Tendons connect muscles to bones, and tibia is a bone neither are joint types. Ligaments link bones, and femur is a bone, but this pairing doesn't define a joint category. Diarthrosis refers to freely movable synovial joints, like the knee, opposite to the question's intent. Synarthroses accurately describe fibrous, fixed joints, critical for structures requiring rigidity, like the cranium, distinguishing them from movable or cartilaginous joints in anatomical classification.

Correct Answer: C

Rationale: Hypertrophy is muscle size increase from training, as resistance stress thickens fibers via protein synthesis, enhancing strength and mass, like in weightlifting. Atrophy is size loss from inactivity, opposite to training's goal. Fatigue is temporary exhaustion, not size change. Hyperplasia, fiber number increase, is rare in humans, unlike hypertrophy's fiber growth. This adaptation reflects muscle's response to mechanical overload, distinct from shrinkage, energy depletion, or theoretical cell addition, central to exercise-induced development.

Correct Answer: D

Rationale: The sternocleidomastoid, from sternum and clavicle to mastoid, rotates and tilts the head side to side, as in looking over the shoulder. Arm abduction is deltoid's role. Breathing involves diaphragm and intercostals, not this neck muscle. Shoulder shrugging is trapezius. Its head-turning action distinguishes it, vital for neck mobility, unlike arm, respiratory, or shoulder functions.

Correct Answer: D

Rationale: Biceps brachii flexes the elbow, bending the forearm toward the arm, while triceps brachii extends it, straightening it. Abduction and adduction involve lateral movement, not their primary elbow focus. Flexion-extension defines their antagonistic pair, distinct from side motions, key for arm bending and straightening.

Correct Answer: D

Rationale: Muscular dystrophy encompasses genetic disorders like Duchenne, progressively weakening muscles via protein defects, leading to loss of function. Sprains are ligament injuries. Fibromyalgia is pain without degeneration. Tendonitis inflames tendons. Muscular dystrophy's degenerative nature distinguishes it, impacting muscle integrity over time.