Skeletal System: Functions, Bone Classifications, Anatomy, and Disorders

What is one function of the skeletal system related to support?

Provides framework for the body and supports soft tissues.

What does the skeletal system protect?

Vital organs, such as the brain, heart, lungs, and spinal cord.

How does the skeletal system facilitate movement?

Osteons and joints act as levers; muscles attach to bones allowing locomotion.

What is stored in the skeletal system to maintain homeostasis?

Minerals, especially calcium and phosphorus.

What process occurs in red bone marrow?

Blood cell production (hematopoiesis), generating red blood cells, white blood cells, and platelets.

What is the function of yellow bone marrow?

Stores fats in adipose tissue.

How do osteoblasts influence metabolism?

They release osteocalcin, which affects glucose metabolism and fat storage.

What are the four classifications of bones?

Long, short, flat, and irregular bones.

What is a characteristic of long bones?

They are longer than they are wide and have a diaphysis and epiphyses.

Name an example of a short bone.

Carpals (wrist) or tarsals (ankle).

What do flat bones typically protect?

They often protect organs and provide broad surfaces for muscle attachment.

What are irregular bones?

Bones with complex shapes that do not fit other categories, such as vertebrae.

What is the function of the epiphysis in a long bone?

Expanded ends that articulate with other bones.

What reduces friction at joint surfaces in long bones?

Articular cartilage, which is hyaline cartilage.

What is the epiphyseal plate?

A cartilage growth plate in children that becomes the epiphyseal line after growth ends.

What is contained in the medullary cavity of a long bone?

Yellow marrow in adults and red marrow in certain bones of children.

What type of bone provides strength and surrounds the cavity in long bones?

Compact bone.

What is the periosteum?

A dense connective tissue sheath covering the outer surface of bones.

What type of bone is lighter yet strong, containing spaces filled with marrow?

Spongy (trabecular) bone.

What is hydroxyapatite?

Inorganic component of bone matrix that gives hardness and rigidity.

What do collagen fibers in bone matrix provide?

Tensile strength and flexibility.

What are osteoblasts responsible for?

Building bone and synthesizing organic components of the matrix.

Where are osteocytes located?

Embedded in lacunae within the bone matrix.

What is the function of osteoclasts?

To break down bone (resorption) to release minerals and remodel bone.

What is the structure of an osteon?

Composed of lamellae, with a Haversian canal containing blood vessels and nerves.

What does the axial skeleton consist of?

Skull, hyoid bone, auditory ossicles, vertebral column, and thoracic cage.

Name a component of the appendicular skeleton.

Pectoral girdles or limbs such as humerus and femur.

What is a simple (closed) fracture?

A bone crack or break that does not penetrate the skin.

What is a compound (open) fracture?

A break that penetrates the skin, increasing infection risk.

What type of fracture breaks the bone into several small fragments?

Comminuted fracture.

What characterizes a greenstick fracture?

An incomplete break common in children where one side is bent and the other is broken.

What is a pathological fracture?

A fracture due to weakened bone from conditions like osteoporosis.

What is osteoporosis?

A condition characterized by reduced bone mass and tissue deterioration, leading to increased fracture risk.

What are some risk factors for osteoporosis?

Aging, postmenopausal status, low body weight, inactivity, calcium/vitamin D deficiency.

What are symptoms of osteoporosis?

Fragile bones, fractures with minimal trauma, back pain, and height loss.

What can help prevent/manage osteoporosis?

Adequate calcium/vitamin D, weight-bearing exercise, medications, and fall prevention.

What is scoliosis?

An abnormal lateral curvature of the spine, sometimes with vertebral rotation.

What are common symptoms of scoliosis?

Uneven shoulders/hips and rib prominence.

What management options exist for scoliosis?

Observation for mild cases, bracing, or surgery for severe cases.

What is osteoarthritis?

A degenerative joint disease marked by the breakdown of articular cartilage.

What are symptoms of osteoarthritis?

Joint pain, stiffness, reduced range of motion, and swelling.

What management strategies exist for osteoarthritis?

Pain relief, physical therapy, weight management, and sometimes joint replacement.