Chapter 4 Skeleton Flashcards
Function
Support the body Protect soft organs Allow Movement due to attached skeletal muscles Store minerals and fat Blood cell formation (hematopoiesis)
Parts of the skeletal system
Subdivisions
Bones
Joints
Cartilages
Ligaments
Axial
Appendicular
2 basic types of bone tissue
Compact
Sponges
Long bones
Longer than wides haft with head at both ends
Compact bone
All of the bones of the limbs (except wrist, ankle, and kneecap)
Short bones
Cube shaped
Spongey bone
Bones of the wrist and ankle
Sesame if bones are a type of short bone which form within tendons (patella)
Flat bones
Thin
Flattened
Curved
Too thin layers of compact bone surround a layer of spongy bone
Irregular bones
Irregular shape
Do not fit into other bone classification categories
Ex
Vertebrae
Diaphysis
Shaft
Composed of compact bone
Epiphysis
Ends of the bone
Spongy bone
Periosteum
Outsider covering of the diaphysis
Fibrous connective tissue membrane
Perforating (Sharpey’s) fibers
Secure periosteum to underlying bone
Arteries
Supply bone cells with nutrients
Articulate Cartilage
Covers the external surface of the epiphyses
Hyaline cartilage
Decreases friction
Epiphyseal plate
Flat plate of hyaline cartilage seen in young, growing bone
Epiphyseal line
Remnant of the epiphyseal plate
Adult bones
Marrow (medullary) cavity
Cavity inside the shaft
Yellow marrow (fat) in adults
Red marrow for blood cell formation in infants
Where is red marrow located in adults?
Situated and cavities of spongy bone and epiphyses of some long bones
Surface features of bones
Sites of attachment for muscles, tendons, and ligaments
Passages for nerves and blood vessels
Categories of bone bone marking
Projections or processes- grow out from the bone surface and terms begin with t
Depressions or cavities- indentations and terms begin with f
Osteon (haversian) system
A unit of bone containing central canal and matrix rings
Central (haversian) canal
Opening in the center of an osteon
Carries blood vessels and nerves
Lacunae
Cavities containing bone cells (osteocytes)
Arranged in concentric rings called lamellae
Lamellae
Rings around the central canal
Sites of lacunae
Canaliculi
Tiny canals
Radiate from the central canal to lacunae
Form transport system connecting all bone cells to a nutrient supply
What kind of cartilage is the skeleton in embryos
Hyaline
Cartilage remains in
Bridge of the nose
Part of ribs
Joints
What allows for lengthwise growth of long bones during childhood
Epiphyseal
Old cartilage is
Ossified
Process of cartilage becoming bone
Broken down
Enclosed cartilage is digested away, opening up a medullary cavity
Bone replaces cartilage through osteoblasts
Bones are remodeled in response to 2 factors
Blood calcium levels
Pull of gravity and muscles in the skeleton
Appositional growth
Bones grow in width
Osteocytes
Mature bone cells
Osteoblasts
Bone forming cells
Osteoclasts
Giant bone destroying cells
Break down bone matrix for remodeling and release of calcium in the parathyroid hormone
Repair of bone fracture
Hematoma- blood-filled swelling is formed
Break is splinted by fibrocartilage to form a callus
Fibrocartilage Callus is replaced by a bony callus
Bony callus is in remodeled it to form a permanent patch
Two sets of bones in the skull
Cranium
Facial
Joined by sutures
Only the mandible is attached by a freely moveable joint
Axial skeleton
Forms the longitudinal axis of the body Divided into three parts skull vertebral column the bony thorax
Paranasal sinuses
Hollow portions of bones surrounding the nasal cavity
Lighten the skull
Give resonance and amplification voice
Hyoid bone
Only bone that does not articulate with another bone
Serves as a moveable base for the tongue
Swallowing and speech
Fetal skull
Large in comparison to total length of infant
1/4 bodyweight compared to adult skull which is 1/8
Fontanels
Fibrous membrane connecting the cranial bones
Allow skull compression during birth
Allow brain to grow
Convert to bone within 24 months of birth
Comminuted Fracture
bone breaks into many fragments
Compression Fracture
bone is crushed
Depressed Fracture
broken bone portion is pressed inward
Impacted Fracture
broken bone ends are forced into each other
Spiral Fracture
ragged break occurs when excessive twisting forces are applied to the bone
Greenstick Fracture
bone breaks incompletely
the vertebral column
each vertebrae has a given name according to its location
24 single vertebral bones
separated by vertebral discs
how many vertebrae are in the neck?
7 cervical vertebrae
how many vertebrae are in the chest region?
12 thoracic vertebrae
how many vertebrae are associated with the lower back?
5 lumbar vertebrae
how many vertebrae fuse together to form two composite bones?
What are these bones called?
9 vertebrae
sacrum
coccyx
the characteristics of the primary curvatures are the spinal curvatures of the thoracic and sacral regions are…
present from birth
form a c-shaped curvature as in newborns
the characteristics of the secondary curvatures are the spinal curvatures of the cervical and lumbar regions
develop after birth
form an s-shaped curvature as in adults
sacrum
formed by the fusion of 5 vertebrae
coccyx
formed by the fusion of 3-5 vertebrae
tailbone, or remnant of a tail that other vertebrates have
the bony thorax
forms a cage to protect major organs 3 parts sternum ribs thoracic cavity
ribs
true ribs (pairs 1-7) false ribs (pairs 8-12) floating ribs (pairs 11-12)
