Functions and Structure of the Skeletal System

Functions of the skeletal system

Support, protection, movement, storage, blood cell formation, and hormone production.

Function of red bone marrow

Hematopoiesis (blood cell formation).

Stored in yellow bone marrow

Fat (energy storage).

Tissues found in bone

Connective (osseous, cartilage), nervous, epithelial (in blood vessels), muscle (skeletal muscle tissue).

Bones in the axial skeleton

Skull, vertebral column, and rib cage.

Function of the axial skeleton

Protects vital organs.

Bones in the appendicular skeleton

Limbs and girdles (pectoral and pelvic).

Function of the appendicular skeleton

Facilitates movement and flexibility.

Bones of the upper limb

Humerus, radius, ulna, carpals, metacarpals, phalanges.

Bones of the lower limb

Femur, tibia, fibula, tarsals, metatarsals, phalanges.

Difference between pectoral and pelvic girdles

Pectoral: clavicle & scapula; allows mobility. Pelvic: ilium, ischium, pubis; supports weight and protects organs.

Difference between male and female pelves

Female: wider, shallower, pubic arch >90°, larger inlet/outlet. Male: narrower, deeper, pubic arch <90°.

Parts of a long bone

Diaphysis, epiphysis, epiphyseal plate, articular cartilage, periosteum, endosteum, marrow cavity.

Function of the periosteum

Outer covering that contains nerves and blood vessels.

Four bone classifications

Long (e.g., femur), short (carpals), flat (ribs), irregular (vertebrae).

Types of bone formation

Intramembranous and endochondral ossification.

Bone remodeling

The process of bone renewal involving osteoblasts and osteoclasts.

Steps in bone fracture repair

1. Hematoma formation 2. Fibrocartilage callus 3. Bony callus 4. Bone remodeling.

Components of treating fractures

Reduction and immobilization.

Regions of the vertebral column

Cervical, thoracic, lumbar, sacral, coccygeal.

Types of ribs

True: attach directly to sternum. False: connect via cartilage. Floating: do not connect to sternum.

Structural classification of joints

Fibrous, cartilaginous, synovial.

Functional classification of joints

Synarthroses (immovable), amphiarthroses (slightly movable), diarthroses (freely movable).

Relationship between joint mobility and stability

More mobility = less stability and vice versa.

Types of synovial joints

Plane, hinge, pivot, condylar, saddle, ball-and-socket.

Movements allowed by a ball-and-socket joint

Flexion/extension, abduction/adduction, rotation, circumduction.

Definition of flexion

Decreasing the angle of a joint.

Definition of extension

Increasing the angle of a joint.

Definition of hyperextension

Extending beyond anatomical position.

Definition of abduction

Moving a limb away from the body's midline.

Definition of adduction

Moving a limb toward the body's midline.

Definition of circumduction

A circular movement that combines flexion, extension, abduction, and adduction.

Definition of rotation

Turning a bone around its own axis.

How bones create movement

Muscles pull on bones via tendons acting as levers at joints.

Types of muscle contractions

Isometric and isotonic.

Definition of origin and insertion

Origin: muscle attachment to a stationary bone. Insertion: attachment to the movable bone.