22.What is the primary function of the periosteum? A. Cushioning joints B. Covering articular surfaces C. Nourishing bones D. Producing red blood cells E. Storing fat 23. The term "cranial"is synonymous with which directional term? A. Inferior B. Superior C Anterior D. Posterior E. Lateral 24.Which bone type is characterized by its ability to reduce friction and protect tendons? A. Long Bones B. Short Bones C. Flat Bones D. Irregular Bones E. Sesamoid Bones 25. The thoracic cavity is separated from the abdominopelvic cavity by which structure? A. Peritoneum B. Pleura C. Diaphragm D Rib Cage E. Mediastinum 26.Which movement involves turning the palm of the hand downward? A. Supination B Pronation C. Rotation D. Circumduction E. Protraction 27. What is the primary function of osteoclasts in bone remodeling? A. Bone formation B. Bone resorption C. Calcium storage D. Hematopoiesis E development

## Step 1<br />The primary function of the periosteum is to nourish the bone. It is a membrane that covers the outer surface of all bones, except for the joints of long bones. The periosteum consists of an outer fibrous layer and an inner osteogenic layer. The osteogenic layer contains osteoblasts and osteoclasts, which are involved in bone formation and resorption, respectively. Therefore, the correct answer is C. Nourishing bones.<br /><br />## Step 2<br />The term "cranial" refers to the skull or cranium, which houses the brain. The term "cranial" is synonymous with the directional term "superior," which means "toward the head" or "above." Therefore, the correct answer is B. Superior.<br /><br />## Step 3<br />Sesamoid bones are characterized by their ability to reduce friction and protect tendons. The most well-known sesamoid bone is the patella (kneecap). These bones are typically small, round, and embedded in tendons. Therefore, the correct answer is E. Sesamoid Bones.<br /><br />## Step 4<br />The thoracic cavity is separated from the abdominopelvic cavity by the diaphragm. The diaphragm is a dome-shaped muscle that plays a crucial role in respiration. When it contracts, it flattens, allowing the lungs to expand and fill with air. Therefore, the correct answer is C. Diaphragm.<br /><br />## Step 5<br />Turning the palm of the hand downward is called pronation. In anatomical terms, pronation is the rotation of the hand and forearm so that the palm faces backward or downward. Therefore, the correct answer is B. Pronation.<br /><br />## Step 6<br />Osteoclasts are involved in bone remodeling, and their primary function is bone resorption. They break down the bone tissue, which is essential for the maintenance, repair, and remodeling of bones. Therefore, the correct answer is B. Bone resorption.