Skeletal System - Axial (235 #7) Flashcards
axial skeleton
the bones that lie around the longitudinal axis of the human body: cranium = 8 face = 14 auditory ossicles = 6 hyoid bone = 1 ribs = 24 sternum = 1 vertebrae = 26 TOTAL = 80!
LONG bones
1) greater length than width
2) contain shaft, variable number of extremities or epiphyses
3) slightly curved for strength
4) mostly compact bone tissue in diaphysis and spongy in epiphyses
5) femure, tib/fib, humerus, ulna, radius, phalanges
SHORT bones
1) somewhat cube-shaped, nearly equal in length and width
2) consist of spongy bone except at the surface
3) most carpals & tarsals
FLAT bones
1) generally thin, composed of two nearly parallel plates of compact with layer of spongy between.
2) protection, area for muscle attachment
3) cranial bones, sternum & ribs, scapulae
IRREGULAR bones
1) complex shapes that cannot be grouped
2) vertebrae, hip bones, some facial bones, calcaneus
SESAMOID bones
1) develop in tendons with considerable friction, stress and tension.
2) may vary in #, not always completely ossified
3) protect tendons from excessive wear and tear, often change direction of pull of a tendon to increase mech advantage
4) patellae, palms, soles.
SUTURAL bones
small bones located in sutures between some cranial bones - number varies.
Red Bone Marrow Locations
1) flat - ribs, sternum, skull
2) irregular - vertebrae, hips
3) long - proximal femur & humerus
4) short - few
Surface Markings - Depressions/Openings
Sites allowing the passage of soft tissues (nerves, blood vessels, ligaments, tendons) or formation of joints
1) Fissure
2) Foramen
3) Fossa
4) Sulcus
5) Meatus
Surface Markings - Processes
Projections or outgrowths on bone that form joints or attachment points for connective tissue (ligaments, tendons). JOINTS: 1) condyle 2) facet 3) head ATTACHMENT POINTS: 1) Crest 2) Epicondyle 3) Line 4) Spinous Process 5) Trochanter 6) Tubercule 7) Tuberosity
Fissure
narrow slit between adnacent parts of bones through which blood vessels or nerves pass
Foramen (Foramina)
Opening through which blood vessels nerves or ligaments pass
Fossa
shallow depression
Sulcus
furrow along bone surface that accomodates blood vessel, nerve or tendon
Meatus
Tubelike opening (e.g. external auditory meatus of temporal bone)
Condyle
Large round protuberance with a smooth articular surface at end of bone
Facet
Smooth, flat, slighly concave or convex articular surface (on vertebrae)
Head
Usually rounded articular projection supported on neck of bone
Crest
Prominent ridge or elongated projection
Epicondyle
Epi = above. Typically roughened projection above condyle
Line
Long, narrow ridge or border (less prominent than crest)
Spinous Process
Sharp, slender projection