Which gland produces sebum to lubricate the skin and hair?

A. Osteoclast:Osteoclasts resorb (break down) bone matrix during remodeling rather than forming new bone.
B. Osteoblast:Osteoblasts synthesize osteoid and initiate its mineralization, producing new bone tissue during growth and repair.
C. Osteocyte:Osteocytes are mature bone cells embedded in matrix that maintain bone tissue and act as mechanosensors rather than actively forming new bone.
D. Chondrocyte:Chondrocytes produce and maintain cartilage matrix and are not the primary cells responsible for bone formation.

A. Medullary cavity:The medullary cavity is the hollow central space within the diaphysis that contains bone marrow; it is not where bone lengthening takes place.
B. Epiphyseal plate:The epiphyseal plate (growth plate) is the area of hyaline cartilage between the diaphysis and epiphysis where new bone is produced, leading to longitudinal bone growth during development.
C. Periosteum:The periosteum is a dense connective tissue layer covering the outer surface of bones and contributes to bone thickness and repair rather than length.
D. Articular cartilage:Articular cartilage covers the ends of bones in joints to provide a smooth surface for movement but is not involved in bone growth.