Skeletal system (Lecture) Flashcards
Parts of the skeletal system
Bones (skeleton)
Joints
Cartilages
Ligaments
Functions of Bones
Support of the body
Protection of soft organs
Movement due to attached skeletal
muscles
Storage of minerals (Ca and P) and fats
Skeletal System Divided into two divisions
Axial Skeleton and Appendicular skeleton
Blood cell formation
hematopoiesis
Two basic types of osseous - bone tissue
Compact Bone - Dense and Homogenous
Spongy Bone - Small needle-like pieces of bone
- many open spaces
-Typically longer than wide
- Have a shaft with heads at both ends
Long bones ( Femur, Humerus)
Generally cube-shape
Contain mostly spongy bone
Short bones (Carpals and tarsals)
form within tendons
Sesamoid bones (patella or kneecap)
Thin and flattened, usually curved
Thin layers of compact bone around a layer of spongy bone
Flat bones (skull, ribs and sternum)
Irregular shape
- Do not fit into other bone classification
categories
Irregular bones (Vertebrae and hip)
Composed of compact bone
Diaphysis
-Ends of the bone
- Composed mostly of
spongy bone
Epiphysis
- Outside covering of the diaphysis
- Fibrous connective tissue membrane
Periosteum
Supply bone cells with nutrients
Arteries
Secure periosteum to underlying bone
Sharpey’s fibers
-Covers the external surface of the epiphyses
- Made of hyaline cartilage
-Decreases friction at joint surfaces
Articular cartilage
-Cavity of the shaft
-Contains yellow marrow (mostly fat) in adults
- Contains red marrow (for blood cell
formation) in infants
Medullary Cavity
- Surface features of bones
- Sites of attachments for muscles, tendons,
and ligaments - Passages for nerves and blood vessels
- Categories of bone markings
Bone Markings
grow out from the bone surface
Projections or processes
A unit of bone
Osteon (Haversian System)
- Opening in the center of an osteon
- Carries blood vessels and nerves
Central (Haversian) canal
- Canal perpendicular to the central canal
- Carries blood vessels and nerves
Perforating (Volkman’s) canal
- Cavities containing bone cells (osteocytes)
- concentric rings
Lacunae
- Rings around the central canal
- Sites of lacunae
Lamellae
-Tiny canals
-Radiate from the central canal to lacunae
- Form a transport system
Canaliculi
Areas where cartilage remains
Bridge of the nose
Parts of ribs
Joints
Types of Bone Cells
Osteocytes
Osteoblasts
Osteoclasts
Mature bone cells
Osteocytes
Bone forming cells
Osteoblasts
- Bone-destroying cells
- Break down bone matrix for remodeling and
release of calcium
Osteoclasts
is a process by both
osteoblasts and osteoclasts
Bone remodeling
break that does not penetrate the skin
Closed (simple) fracture
broken bone penetrates through the skin
Open (compound) fracture
swelling) is formed due to broken blood vessels
Hematoma (blood-filled swelling)
Break is splinted by fibrocartilage to form a
callus – cartilage matrix, bony matrix,
collagen fibers – capillaries also form again
Forms the longitudinal part of the body
Axial Skeleton
Skull 2 sets of bones
Cranium, Facial Bones
Axial skeleton is divided into three parts
Skull, Vertebral column, Bony thorax
Hollow portions of bones surrounding
the nasal cavity
Paranasal Sinuses
Functions of paranasal sinuses
Lighten the skull
Give resonance and amplification to voice
The only bone that does not articulate with another bone
Hyoid Bone
fibrous membranes connecting
the cranial bones
- Soft spots
-Allow the brain to grow and for easier delivery - Convert to bone within 24 months after birth
Fontanelles
separated by intervertebral discs
Vertebrae
Forms a cage to protect major
organs
Bony thorax
Bony thorax is made up of three parts
Sternum
Ribs
Thoracic Vertebrae
bones of the Limbs (appendages) Pectoral girdle, Pelvic girdle
126 bones
The Pectoral (Shoulder) Girdle Composed of two bones
Clavicle - collarbone
Scapula - Scapula
The arm is formed by a single bone
Humerus
The forearm has two bones
Ulna and Radius
Hip bones composed of three pair of fused bones
Ilium
Ischium
Pubic bone
The thigh has one bone, the heaviest and strongest bone in the body
Femur (Thigh bone)
The leg has two bones
Tibia and Fibula
Bones of the foot are arranged to
form three strong arches
Two longitudinal
One transverse
Articulations of bones
Joints
Ways joints are classified
- Functionally
- Structurally
immovable joints
Synarthroses
slightly moveable joints
Amphiarthroses
freely moveable joints
Diarthroses
Generally immovable
Fibrous joints
Immovable or slightly moveable
Cartilaginous joints
Freely moveable
Synovial joints
Bones united by fibrous tissue
Fibrous Joints
Bones united by fibrous tissue examples
Sutures in skull
Syndesmoses
Bones connected by cartilage
Cartilaginous Joints
Cartilaginous Joints example
Pubic symphysis - pelvis
Intervertebral joints - spinal column
Bones connected by cartilage
Pubic symphysis - pelvis
Intervertebral joints – spinal column
– flattened fibrous sacs
Lined with synovial membranes
Filled with synovial fluid
Bursae
Elongated bursa that wraps around a tendon
Tendon Sheath