Ch. 6 Skeletal System: Bone Tissue and Functions

Long Bone

Examples include humerus and femur.

Flat Bone

Thin, flattened bone shape.

Short Bone

Cube-shaped bones, like carpals.

Sesamoid Bone

Bone embedded within a tendon.

Irregular Bone

Complex shapes, like vertebrae.

Articular Cartilage

Covers bone ends, reduces friction.

Spongy Bone

Lightweight bone with holes, contains marrow.

Compact Bone

Dense bone providing strength and support.

Diaphysis

Shaft of a long bone.

Epiphysis

Ends of long bones, contains spongy bone.

Metaphysis

Region between epiphysis and diaphysis.

Red Bone Marrow

Site of blood cell production.

Yellow Bone Marrow

Stores triglycerides, found in medullary cavity.

Endosteum

Lines the medullary cavity of bones.

Periosteum

Outer membrane covering bones.

Hematopoiesis

Blood cell production in red marrow.

Cranial Cavity

Houses the brain.

Thoracic Cavity

Contains lungs and heart.

Pelvic Cavity

Contains reproductive organs.

Vertebral Cavity

Houses the spinal cord.

Hyaline Cartilage

Minimal fibers, ideal for joints.

Fibrocartilage

Dense, strong cartilage for cushioning.

Elastic Cartilage

Contains elastin fibers for flexibility.

Articular Cartilage Function

Reduces friction at joint surfaces.

Vertebral Cartilage Function

Absorbs impact between vertebrae.

Bone Remodeling

Continuous process of bone formation and resorption.

Skeletal System Functions

Supports, protects, and stores minerals.

Bone Tissue Composition

Highly vascularized with mineralized matrix.

Epiphysial Plate

Growth region in long bones during adolescence.

Periosteum

Dense tissue covering bone, aids growth and repair.

Medullary Cavity

Hollow space in long bones containing yellow marrow.

Endosteum

Membrane lining medullary cavity, contains osteoblasts and osteoclasts.

Perichondrium

Connective tissue surrounding cartilage, supports growth.

Chondrocytes

Cells responsible for forming cartilage.

Osteoblast

Bone-forming cell derived from osteogenic cells.

Osteocyte

Mature osteoblast that maintains bone tissue.

Osteogenic Cell

Stem cell that differentiates into bone cells.

Osteoclast

Cell that breaks down bone tissue, derived from WBCs.

Hematopoietic Stem Cells

Stem cells that produce blood cells.

Yellow Bone Marrow

Fat storage tissue in medullary cavity.

Red Bone Marrow

Site of blood cell production (hematopoiesis).

Collagen

Protein providing flexibility and tensile strength to bone.

Hydroxyapatite

Mineral salts providing hardness to bone structure.

Calcium Phosphate

Major inorganic component of bone mineral.

Epiphyseal Line

Remnant of growth plate in adult bones.

Osteon

Structural unit of compact bone, contains Haversian systems.

Lacunae

Small spaces housing osteocytes in bone matrix.

Canaliculi

Channels connecting lacunae, allowing nutrient exchange.

Circumferential Lamellae

Rings of bone matrix surrounding outer bone.

Concentric Lamellae

Rings of calcified matrix within osteons.

Interstitial Lamellae

Remnants of older osteons between current osteons.

Vascularization

Blood supply through central canals in osteons.

Volkmann's Canals

Perforating canals connecting blood vessels to outer bone.

Bone Composition

Bone consists of 25% water, 25% proteins, 50% minerals.

Bone Remodeling

Process of bone resorption and formation.

Fracture Repair

Process involving periosteum and osteoblast activity.

Growth Plate Function

Site of active cell division for bone elongation.

Spongy Bone

Majority of epiphyses in long bones.

Compact Bone

Superficial bone along longitudinal length.

Ossification

Process of forming new bone.

Embryogenesis

Bone formation in an embryo.

Adolescent Growth

Growth of bones until adulthood.

Bone Remodeling

Continual process of bone renewal.

Fracture Repair

Restoration of bone after injury.

Intra-membranous Ossification

Produces spongy bone directly.

Endochondral Ossification

Cartilage replaced by bone.

Osteoblasts

Cells that secrete bone matrix.

Calcification

Recruitment of calcium and phosphates.

Periosteum

Membrane formed around bone surface.

Chondroblasts

Stem cells forming cartilage.

Chondrocytes

Cartilage cells that secrete fibers.

Primary Ossification Site

Location where spongy bone first forms.

Medullary Cavity

Hollow space within diaphysis.

Secondary Ossification Centers

Regions where bone replaces cartilage.

Articular Cartilage

Covers surface of epiphyses.

Epiphyseal Growth Plate

Responsible for longitudinal bone growth.

Lateral Bone Growth

Thickening of bones.

Longitudinal Bone Growth

Increase in bone length.

Human Growth Hormone

Stimulates bone and muscle growth.

Pituitary Gland

Secretes hormones regulating growth.

Hormonal Regulation

Control of bone growth by hormones.

Bone Growth Completion

Usually by ages 18-21.

Puberty Impact

Accelerates adolescent bone growth.

Gender Differences in Growth

Variations in growth patterns between sexes.

Collagen Fibers

Protein fibers providing structure to bones.

Mesenchymal Stem Cells

Develop into various cell types during growth.

Human Growth Hormone (hGH)

Stimulates growth of bone and muscle.

Side Effects of hGH

Can lead to fractures and muscle atrophy.

Growth Spurt

Rapid increase in height during puberty.

Estrogen

Promotes widening of female pelvis.

Testosterone

Contributes to male growth during puberty.

Epiphyseal Plates

Growth areas that close after puberty.

Osteoclasts

Cells that break down bone tissue.

Osteoblasts

Cells responsible for bone formation.

Acromegaly

Abnormal thickening of bones from excess tissue.

Osteoporosis

Condition of weakened bones due to calcium loss.

Rickets

Bone disease due to vitamin D deficiency.

Osteomalacia

Softening of bones due to mineral deficiency.

Calcium and Phosphorus

Essential minerals for bone growth and remodeling.

Vitamin A

Stimulates osteoblast activity for bone formation.