A&P Ch.6 The Skeletal System Flashcards
What are the 5 functions of the the skeletal system?
- Support
- Storage of calcium salts and lipids (yellow marrow)
- Blood cell production (red marrow)
- Protection
- Leverage (levers for skeletal muscles)
What are the 4 types of bones?
- Long bone (ex. Femur, typical bone)
- Flat bone (ex. Parietal bone)
- Irregular bone (ex. Vertebra)
- Short bone (ex. Carpals)
Typical Structure of the long bones:
Diaphysis
Central shaft
Contains the marrow cavity
Typical Structure of the long bones:
Epiphyses
The expanded portion at each end covered by articular cartilage
This area is what articulates with an adjacent bone at a joint.
Typical structure of the long bone:
Marrow cavity
Contains the BONE MARROW.
MARROW CAVITY is surrounded by the DIAPHYSIS
Typical structure of a long bone:
Compact bone
Solid bone
Forms the DIAPHYSIS
Typical structure of a long bone:
Spongy bone or cancellous bone
Resembles a network of bony rods or struts separates by spaces.
The spongy bone fills the EPIPHYSES
Has no osteons
Typical structure of a long bone:
Periosteum
Forms the OUTER SURFACE of the bone
Ligaments and tendons attach here
Provides a route for circulatory and nervous supplies
Participated in bone growth and repair
Has a fibrous outer layer and a cellular inner layer
Typical structure of a long bone:
Endosteum
Lines the marrow cavity and other internal surfaces.
Active during bone growth and repair/remodeling
Osteocytes
Mature OSTEOBLASTS cells
Bone cells
Arranged in a concentric layer (circular layer) around the CENTRAL CANAL
Lacunae
Small pockets
House the osteocytes
found in both SPONGY & COMPACT bone
Located between the LAMELLAE
LAMELLAE
Narrow sheets of calcifies matrix
Canaliculi
Small channels
Radiate through the matrix
Interconnect LACUNAE and link them to nearby blood vessels
Osteon
Haversian system
The basic functional unit for compact bone
OSTEOCYTES are arranged in a concentric layer (circular pattern) with in the OSTEON
Central canal
Haversian canal
Contains one or more blood vessels that connect to the PERFORATING CANAL
LAMELLAE run cylindrically parallel to the long axis of the CENTRAL CANAL
Perforating canal
Provides a pathway for the blood vessels of the CENTRAL CANALS to connect and supply the vessels of the PERIOSTEUM and the MARROW CAVITY
Trabeculae
Rods and plates formed by the LANELLAE with in SPONGY BONES
Not found in the COMPACT BONE
Where is a layer of COMPACT BONE not found?
Inside joint capsules where ARTICULAR CARTILAGES are found.
This type of bone is found typically where stresses comes from a limited range of direction
Compact bone
Functions of the cells:
Osteocytes
Maintain normal bone structure by recycling the calcium salts in the bony matrix surrounding them.
Assists in repairs
Functions of the cells:
Osteoclasts
Contain 50 or more nuclei
Bone breakers
Dissolve bone with an acid and enzyme secretion releasing stored minerals back into the system through a process called OSTEOLYSIS or RESORPTION.
Help regulate calcium and phosphate concentrations in the body fluids
Functions of the cells:
Osteoblasts
Bone makers
Create bone in a process called OSTEOGENESIS
