Locomotion and Movements

Impaction is a fracture in which the bones involved are driven into each other.

The ethmoid bone is a bone in the skull separating the nasal cavity from the brain. It is cubical in shape and is a lightweight bone.

The supraorbital foramen is a bony elongated path located above the orbit and under the forehead. It lies directly under the eyebrow.

This pelvis is a female pelvis with masculine features, including a wedge or heart shaped inlet caused by a prominent sacrum and a triangular anterior segment.

Sutural bones are very small bones located specifically within the sutural joints, between the cranial bones. These bones are also known as wormian bones, are the marker for some diseases and are important in the primary diagnosis of brittle bone disease.

Osteoporosis is the most common cause of pathological fracture. It generally involves failure of bone tissue formation or maintenance. Thus, bones appear translucent in an X-ray.

These muscles are more spindle shaped, with the muscle belly being wider than the origin and insertion. Prominent examples are Biceps Brachii and Psoas major.

The Ethmoid bone differs from the other bones in the cranium in that it is a spongy bone. It divides the nasal cavity from the brain.

Saddle joints allow bending motion in several directions without sliding. The carpal-metacarpal joint of the thumb is an example of saddle synovial joints.

Troponin is a complex of three regulatory proteins; troponin C, troponin I and troponin T,  and is integral to muscle contraction in skeletal muscles and cardiac muscles, but not in smooth muscles.

Pycnodysostosis is a lysosomal storage disease of the bone caused by a mutation in the gene that codes the enzyme cathepsin K.

Troponin binds to actin in thin myofilaments to hold the actin-tropomyosin complex in place. Because of it, myosin cannot bind actin in relaxed muscle.

This is the wrong statement. In the presence of high concentrations of Ca²⁺, the Ca²⁺ binds to troponin, changing its shape and so moving tropomyosin from the active site of the actin. The myosin filaments can now attach to the actin, forming a cross-bridge.

This skeletal muscle is anaerobic, glycolytic and white.  In small animals like rodents this is the major fast muscle type, explaining the pale colour of their flesh.

The capitate bone is the largest of the carpal bones in the human hand and occupies the center of the wrist.