Chapter 8 - A &P

Support

Support

Provides a rigid framework that maintains body shape.

Protection

Bones encase and protect vital organs.

Movement

Serves as levers for muscles; occurs when muscles contract and pull on bones.

Mineral Storage

Primarily stores calcium and phosphorus for muscle contractions, nerve function, and blood clotting.

Hematopoiesis

Blood cell formation occurring in red bone marrow.

Long Bones

Cylindrical bones found in limbs, e.g., femur and humerus.

Short Bones

Bones providing stability with little movement, e.g., carpals.

Flat Bones

Thin bones that protect organs and serve as muscle attachment points, e.g., skull and ribs.

Irregular Bones

Complex-shaped bones for specific functions, e.g., vertebrae.

Sesamoid Bones

Small, round bones embedded in tendons, e.g., patella.

Diaphysis

The shaft of long bones, composed of compact bone for strength.

Medullary Cavity

Contains yellow marrow, primarily composed of fat cells.

Epiphyses

Ends of long bones containing spongy bone with red marrow.

Periosteum

Dense fibrous membrane covering the surface of bones.

Endosteum

Thin membrane lining the medullary cavity.

Osteocytes

Mature bone cells that maintain bone tissue.

Osteoblasts

Bone-building cells that secrete the bone matrix.

Osteoclasts

Bone-resorbing cells that break down bone tissue.

Compact Bone

Dense outer layer of bones containing osteons for strength.

Spongy Bone

Lightweight bone found in epiphyses that helps reduce overall bone weight.

Cartilage

Flexible tissue at joints that provides cushioning.

Endochondral Ossification

Most bones form from cartilage models replaced by bone tissue.

Intramembranous Ossification

Flat bones form directly from connective tissue.

Epiphyseal Plate

Cartilage layer allowing for longitudinal bone growth.

Joint Types

Synarthroses (immovable), Amphiarthroses (slightly movable), Diarthroses (freely movable).

Synarthroses

Immovable joints, such as sutures between skull bones.

Amphiarthroses

Slightly movable joints connected by cartilage.

Diarthroses

Freely movable joints categorized by movement type.

Ball-and-Socket Joint

Allows for multi-directional movement, e.g., shoulder and hip.

Hinge Joint

Allows movement in one plane, e.g., elbow and knee.

Pivot Joint

Allows rotational movement, e.g., between neck vertebrae.

Joint Capsule

Encases the joint and is lined with synovial membrane.

Synovial Fluid

Lubricates the joint to reduce friction.

Osteosarcoma

Most common and aggressive bone cancer, often found in distal femur.

Chondrosarcoma

Cancer of cartilage usually affecting pelvic bones.

Osteoporosis

Condition characterized by reduced bone density leading to fragility.

Rickets

Vitamin D deficiency causing softening of bones in children.

Osteomalacia

Vitamin D deficiency causing softening of bones in adults.

Paget Disease

Excessive abnormal bone remodeling resulting in weakened bones.

Osteogenesis Imperfecta

Genetic disorder causing brittle bones due to defective collagen.

Osteomyelitis

Infection of bone tissue often caused by bacteria.

Open Fracture

Bone pierces the skin and may require surgery.

Closed Fracture

Bone is broken but does not break the skin.

Complete Fracture

Bone is broken into two or more parts.

Incomplete Fracture

Bone cracks but does not break all the way through.

Transverse Fracture

Fracture across the bone's shaft.

Linear Fracture

Fracture along the length of the bone.

Oblique Fracture

Fracture at an angle to the bone.

Osteoarthritis

Degenerative joint disease where cartilage deteriorates.

Dislocation

Bones are forced out of alignment at a joint.

Sprain

Injury to ligaments around a joint.

Rheumatoid Arthritis

Autoimmune condition causing joint inflammation.

Gouty Arthritis

Accurate acid crystals accumulate in joints, causing inflammation.

Infectious Arthritis

Joint infection caused by bacteria or viruses.

Axial Skeleton

Comprises the skull, vertebral column, and thoracic cage.

Appendicular Skeleton

Includes upper and lower limbs and their girdles.

Pectoral Girdle

Connects upper limbs to the axial skeleton, composed of scapula and clavicle.

Pelvic Girdle

Composed of coxal bones, connecting the lower limbs to the axial skeleton.

Male Skeleton

Generally larger and denser with a narrow pelvis.

Female Skeleton

Wider pelvis with a larger pelvic inlet for childbirth.

Bone Maturation

Bones reach maximum density around age 25.

Bone Density Decrease

Gradual loss begins after age 50 influenced by various factors.

Environmental Factors

Diet, physical activity, and stress affecting bone health.

Osteocytes

Mature bone cells located in small spaces called lacunae.

Matrix

Flexible, gel-like substance of cartilage with collagen fibers.

Avascular Nature

Lack of blood vessels in cartilage leads to slower healing.

Bone Development

Continual renewal and adaptation involving osteoblasts and osteoclasts.

Chondrocytes

Cartilage cells located in lacunae.

Diploe

Spongy bone layer within flat bones providing shock absorption.

Trabeculae

Bony framework that provides strength to cancellous bone.

Microscopic Structure of Bone

Includes both spongy and compact bone with distinct features.

Osteon

Cylindrical unit of compact bone containing central canal.

Central Canal

Contains blood vessels and nerves in osteons.

Lacunae

Small spaces that house osteocytes within bone.

Canaliculi

Channels connecting lacunae for nutrient transport.

Fibrous Membrane

Dense membrane covering surfaces of bones.

Long Bone Growth

Occurs at the epiphyseal plate until adulthood.

Osteoblast Activity

Secretion of organic components of bone matrix.

Osteoclast Activity

Resorption and remodeling of bone tissue.

Primary Ossification Center

Area where bone begins to replace cartilage during development.

Secondary Ossification Center

Additional area of ossification occurring in epiphyses.

Newborn Skeleton Characteristics

Not fully ossified; flexible and allows for growth.

Skull Function

Protects the brain and provides facial structure.

Vertebral Column Composition

Made up of 33 vertebrae divided into several regions.

Thoracic Cage Purpose

Protects heart and lungs with ribs and sternum.

Coxal Bones

Bones forming the pelvic girdle connecting lower limbs.

Muscle Attachment Points

Flat bones provide sturdy sites for muscle anchorage.

Nutrient Supply to Bones

Nourishment provided by blood vessels and periosteum.

Joint Types Classification

Categorized based on structure and movement capabilities.

Injury Healing Process

Bones and joints repair differently based on structure.

Bone Healing Time

Varies depending on severity and location of fracture.

Risk Factors for Osteoporosis

Include aging, hormonal changes, and lifestyle factors.

Primary Function of Joints

Facilitate movement by connecting bones.

Joint Stability Factors

Muscle strength and ligaments contribute to joint stability.

Articular Cartilage Role

Covers joint surfaces to reduce friction.

Synovial Membrane Function

Secretes synovial fluid for lubrication.

Joint Degeneration

May lead to arthritis and impaired movement.

Bone Fracture Types

Classified based on the manner of bone breakage.

Chondrocyte Function

Maintain cartilage structure and integrity.

Function of Trabecular Bone

Provides structural support while minimizing weight.