Skeletal System Flashcards
Hyaline cartilage
Most abundant
Support
Flexibility
Covers ends of bones
Connects ribs to sternum
Supports nose
In respiratory system
Fibrocartilage
Shock absorber
Some flexibility
Strong and compressible
Knees
Discs between vertebrae
Pubis
Major divisions
Axial skeleton
Appendicular skeleton
Functions
Support - against gravity
Protection - brain, spinal cord, organs
Movement - lever
Mineral storage - calcium phosphate
Hormone storage - growth factors
Blood cell formation - red bone marrow
Triglyceride storage - yellow bone marrow
Hormone production - osteocalcin
Long bones (classification)
Longer than wide
Elongated
Shaft plus two ends
E.g. femur, three bones in your fingers
Short bones (classification)
Roughly cubed
E.g. wrist and ankle
Sesamoid bones (type of short bone)
Form or embedded in a tendon
E.g. pisiform and patella.
Flat bone (classification)
Thin
Flattered
Usually curves
E.g. sternum, scapulae, ribs, cranial bones
Irregular bones (classification)
Complicated shaped
E.g. vertebrae, hip bones
Compact bone (gross anatomy)
Dense outer layer
Looks smooth and solid to the eye
Spongy bone (gross anatomy)
Internal
Trabeculae - honeycomb of small needle-like
Spaces filled with red and yellow bone marrow
Trabeculae redesign to account for physical activity
Proximal and epiphysis (gross anatomy)
End of bone
Diaphysis (gross anatomy)
Main/middle section
Epiphyseal line (gross anatomy)
Hyaline cartilage
Growth zones
Produces new cells where the bone can grow
As you age it calcifies
Periosteum (gross anatomy)
Two layers
Sharpey’s fibres connect to the bone
Outer fibrous layer - dense irregular connective tissue
Inner osteogenic layer contains osteoprogenitor cells
Osteoclasts
Osteoblasts
Rich blood and nerve supply
Endosteum
Delicate connective tissue
Covers internal bone surfaces
Covers trabeculae
Lines canals
Osteoclast
Osteoblasts
Osteoprogenitor cells
Stem cells
Differentiate into osteoblasts
Osteoblast cells
Matrix synthesising
Bone growth
Unmineralised ground substance - collagen and calcium-binding proteins
Osteocytes
Mature
Monitor and maintain mineralised matrix
Act as stress sensors
Respond to mechanical stimuli
Comunicate info for bone remodelling and repair
Osteoclast cells
Bone-re absorption
Lye in lacuna
Ruffled border -increases SA for enzymatically degrading the bone and sealing the area off
Bone lining cells
Flat
Found at bone surface where remodelling isn’t happening
Part of endosteum
Compact bone (microscopic structure)
Periosteum
Volkmann’s canal - blood and nerves to enter Haversian canal
Osteon - hollow tubes, collagen fibres, resist to twisting motions
Central canal - blood and nerve that serves osteon
Canaliculi - hair like canals connects lacunae
Spongy bone (microscopic structure)
Trabeculae align along stress helps resist stress
Few cells thick
Irregularly arranged lamellae
No Osteons
Diffusion of nutrients
Chemical composition of bone
30% organic - flexibility, tensile strength (bone cells, fibres )
70% minerals - hardness (calcium phosphate)
Synovial joints - articular catilage
Glassy smooth
Hyaline cartilage
Absorb compression on joint
Ends of bone
Synovial joints - joint cavity
Synovial fluid
Space Surrounding the bones
Synovial joints - articular capsule (inner)
Synovial membrane
Loose connective tissue
Secretes synovial fluid
Rich blood vessel network
Synovial joints - articular capsule (outer)
Fibrous layer
Dense irregular connective tissue
Strengthens so bones aren’t pulled apart
Synovial joints - synovial fluid
Viscous consistency - hyaluronic acid
Slippery, weight-bearing film
Reduces friction
Synovial joints - bursae
Flattened fibrous sacs
Lines worth synovial membrane
Synovial fluid
Prevents rubbing
Synovial joints - fat pads
Adipose tissue
Sill spaces in joint
Protective
Vascularised
Synovial joints - ligaments
Capsular - thickened parts of the fibrous layer
Outside or in capsule (intracapsule ligaments)
Dense connective tissue - collagen
Stop dislocation and lateral movement
Connect bones to bones
Synovial joints - menisci
Fibrocartilage
Shock absorber
Dish/bowl shape for bone to sit in
Synovial joints - tendon sheath
Elongated bursa
Wraps completely around tendon subject to friction
Filled with synovial fluid
Types of synovial joint
Gliding/plane
Hinge
Pivot
Condyloid
Saddle
Ball-and-socket
Gliding/plane joint
Flat articular surfaces
E.g. intercarpal joints, between vertebral articular surfaces
Hinge joint
Cylinder and trough
Flexion and extension
E.g. elbow
Pivot joint
Sleeve and axle
Rotation
E.g. proximal radioulnar
Condyloid joint
Oval articular surfaces
Flexion and extension
Adduction and abduction
E.g. Metacarpophalangeal (knuckle) and wrist
Saddle joint
Articular surface where both are concave and convex
Flexion and extension
Adduction and abduction
E.g. carpometacarpal joints of the thumbs
Ball-and-socket
Cup and spherical ball
Flexion and extension
Adduction and abduction
Rotation
E.g. shoulder and hip joints
Fibrous joints
Bones connected by dense fibroids connective tissue
Allow little movement
Synarthrotic or amphiarthrotic
Fibrous joint types
Structure
Syndesmosis
Fibrous joints - structure
Strong synarthrotic, fibrous joints
Ligaments becomes continuous with the periosteum of the bovine
Interlock/straight
Only found at junctions of the plate bones of the skull
Fibrous joints - syndesmosis
Bound together by an interosseous ligament - long collagenous fibres
Amphiarthrotic
E.g. anterior tibiofibular ligament that connects the distal tibia and fibula
Cartilaginous joints
Connected by hyaline cartilage
No synovial cavity
Synarthrotic or amphiarthrotic
Cartilaginous joint types
Synchondrosis
Symphysis
Cartilaginous joints - Synchondrosis
Connected by hyaline cartilage
As age they ossify to become continuous bone
E.g. the costal joint between the first rib and the manubrium of the sternum
Cartilaginous joints - symphysis
Hyaline cartilage fuses with a flat disc of Fibrocartilage
Shock absorbers
Most found in axial skeleton
Amphiarthrotic
E.g. intervertebral joints between vertebral bodies
Joint classification - synathrosis
Joints that do not provide any movement
Joint classification - amphiarthrosis
Joints that only provide a small degree of of movement
Joint classification - diarthrosis
Joints that allow free movement
