topic 2 pt 1

• What are the primary functions of bones?

  Bones provide rigid support, protect underlying tissues, and store minerals.
• What type of support does cartilage provide?

  Cartilage provides semirigid support.
• What do tendons attach to bones?

  Tendons attach muscles to bones.
• What is the function of ligaments?

  Ligaments hold bones together.
• What are the main functions of the skeletal system?

  • Support
  • Protection
  • Assistance with movement
  • Mineral homeostasis
  • Blood cell production
  • Triglyceride storage
• What is hyaline cartilage?

  Hyaline cartilage is gelatinous, glossy cartilage with evenly distributed collagen fibers.
• Where is hyaline cartilage found?

  Hyaline cartilage is found in the rib cage, bronchi, and articulating surfaces of bones.
• What is fibrocartilage characterized by?

  Fibrocartilage has more collagen bundles than hyaline cartilage and is very tough.
• Where is fibrocartilage found?

  Fibrocartilage is found in the knee, temporo-mandibular joint, and inter-vertebral discs.
• What is elastic cartilage?

  Elastic cartilage has a matrix similar to hyaline but includes elastic fibers.
• Where is elastic cartilage found?

  Elastic cartilage is found in the external ear, epiglottis, and auditory tubes.
• What are the two types of cartilage growth?

  1. Appositional growth: Cartilage is added by chondroblasts to the outside, increasing width.
  2. Interstitial growth: Chondrocytes undergo mitosis within the matrix, increasing length.
• What is the composition of cartilage?

  • Matrix produced by chondroblasts
  • Dense network of collagen and elastic fibers
  • Chondrocytes in lacunae
  • Avascular and aneural
• What is the role of chondrocytes in cartilage?

  Chondrocytes are cartilage cells surrounded by the matrix.
• How does cartilage receive nutrients?

  Cartilage receives nutrients by diffusion from blood vessels in the perichondrium.
• What are the key features of cartilage?

  • Avascular (no blood vessels)
  • Aneural (no nerves)
  • Flexible connective tissue
  • Formed from cells in the perichondrium
• What are osteoblasts?

  Osteoblasts are bone-forming cells that produce the matrix.
• Where do osteoblasts originate?

  Osteoblasts originate in the periosteum.
• What is the function of osteocytes?

  Osteocytes are matrix maintenance cells located in lacunae.
• What are osteoclasts?

  Osteoclasts are bone-destroying cells that break down the matrix.
• Where do osteoclasts originate?

  Osteoclasts originate in red bone marrow.
• What are the components of bone matrix?

  • 35% organic: collagen fibers, proteoglycans
  • 65% inorganic: hydroxyapatite (CaPO4 crystals)
• What happens if collagen is removed from bone?

  If collagen is removed, bone becomes too brittle.
• What happens if minerals are removed from bone?

  If minerals are removed, bone becomes bendable.
• What is the process of bone matrix formation?

  • Formation through ossification or osteogenesis by osteoblasts
  • Collagen produced by Endoplasmic Reticulum and Golgi Apparatus
  • Hydroxyapatite stored in vesicles and released by exocytosis

  
• What are the two types of ossification?

  1. Endochondral ossification: Bone forms from a cartilage template.
  2. Intramembranous ossification: Bone forms from mesenchymal stem cells.
• What are the steps of endochondral ossification?

  1. Mesenchymal cells become osteochondral progenitor cells.
  2. Cells differentiate into chondroblasts forming a cartilage framework.
  3. Blood vessels invade, and osteochondral cells differentiate into osteoblasts.
  4. Osteoblasts deposit new bone matrix.
  5. Woven bone is remodeled.

  
• What are the steps of intramembranous ossification?

  1. Mesenchymal cells within connective tissue differentiate into osteoprogenitor cells.
  2. Osteoprogenitor cells differentiate into osteoblasts.
  3. Osteoblasts form a woven bone matrix.
• What are the differences between woven and lamellar bone?

  • Woven bone: immature, mechanically weak, collagen fibers randomly arranged.
  • Lamellar bone: mature, mechanically strong, collagen fibers parallel in each lamella.

  
• What are the two types of bone growth?

  1. Appositional growth: New bone added to the outside, making bones wider.
  2. Interstitial growth: Osteoblasts produce more matrix from the inside, making bones longer.

  
• What are the classifications of bones?

  • Long bones: e.g., femur, tibia
  • Short bones: e.g., carpals, tarsals
  • Flat bones: e.g., ribs, sternum, skull
  • Irregular bones: e.g., vertebrae, facial bones
• What are the key structures of long bones?

  • Diaphysis: Shaft, largely compact bone
  • Epiphysis: Enlarged end, largely spongy bone
  • Epiphyseal plate: Growth plate made of hyaline cartilage
  • Medullary cavity: Contains red marrow in children, yellow in adults

  
• What is the structure of short, flat, and irregular bones?

  • Sandwich of spongy bone between two layers of compact bone
  • No diaphysis or epiphysis in flat bones
• What happens to the epiphyseal plate as a bone ages?

  • The epiphyseal plate is replaced by bone, forming the epiphyseal line.
  • Growth in length stops when all cartilage cells become bone.
• What are the names and descriptions of key bone features?

  • Head: Enlarged end
  • Body: Main part of bone
  • Neck: Constriction between head and body
  • Margin: Edge
  • Angle: Bend
  • Ramus: Branch off body of bone
  • Crest: Prominent ridge
  • Foramen: Opening
  • Condyle: Smooth rounded articular surface
  • Facet: Small flattened articular surface
  • Fossa: Shallow depression
  • Meatus: Passageway
  • Fissure: Narrow slit

  
• What are the names and descriptions of bone projections?

  • Process: Prominent projection
  • Tubercle: Small rounded bump
  • Tuberosity: Knob, round projection
  • Trochanter: Tuberosities on proximal femur
  • Epicondyle: Near or above a condyle

  
• What are the suffixes used in the skeletal system?

  • -blast: create, build (e.g., osteoblast)
  • -clast: break down (e.g., osteoclast)
  • -cyte: cell (e.g., osteocyte)
• What are the prefixes used in the skeletal system?

  • acetabul: vinegar cup (e.g., acetabulum)
  • append: to hang something (e.g., appendicular skeleton)
  • chondro: cartilage (e.g., chondrocyte)
  • endo: within (e.g., endosteum)
  • lacun: pool (e.g., lacunae)
  • os: bone (e.g., os cox)
  • osteo: bone (e.g., osteoporosis)
  • peri: around (e.g., periosteum)