Bone Function, Development, and Growth: Support, Protection, and Hematopoiesis

What are the primary functions of bones?

Support and protection, body movement, blood cell formation, and storage of inorganic salts.

How do bones support the body?

Bones support the body's weight through structures like the legs, pelvis, and vertebrae.

What bones protect the brain and eyes?

The skull protects the brain and eyes.

What is hematopoiesis?

Hematopoiesis is the formation of blood cells, primarily occurring in the liver, spleen, and bone marrow.

Where is bone marrow found?

Bone marrow is found in the medullary cavities of long bones, in the spaces of spongy bone, and in the osteonic canals of compact bone.

What types of blood cells are produced in bone marrow?

Red blood cells (erythrocytes), white blood cells (leukocytes), and blood platelets (thrombocytes).

What is the role of yellow marrow?

Yellow marrow replaces red marrow with age and stores fat.

What minerals are stored in the bone matrix?

The bone matrix stores calcium salts, primarily calcium phosphate, along with lesser amounts of other minerals.

What are intramembranous bones?

Intramembranous bones are flat bones of the skull formed by osteoblasts depositing a bony matrix between connective tissue sheets.

What happens to osteoblasts after bone formation?

Osteoblasts turn into osteocytes, which maintain the bone and reside in lacunae.

What are fontanels?

Fontanels are the 'soft spots' in an infant's skull that allow for movement through the birth canal.

What are endochondral bones?

Endochondral bones are most bones in the body formed from a model of hyaline cartilage that is replaced by bone.

What is the role of osteoclasts in bone?

Osteoclasts resorb (erode) bone, contributing to bone remodeling.

How does exercise affect bone growth?

Exercise pulls on bones, causing them to thicken and strengthen.

What factors affect bone growth?

Nutrition (e.g., vitamin D), hormonal secretion (growth and sex hormones), and exercise.

What is the epiphyseal disk?

The epiphyseal disk, or growth plate, is responsible for the lengthening of bones during growth.

How often is calcium exchanged in an adult skeleton?

3% to 5% of calcium is exchanged per year in an adult skeleton.

What is the function of articular cartilage?

Articular cartilage cushions the joints and remains on the ends of bones.