Skeletal Systems Flashcards
What are the 6 main functions of the skeletal system?
- Contains red bone marrow for blood cell formation
- Mineral store for calcium and phosphates
- Determines the shape of the body
- Protection of vital organs
- Function as levers by acting with muscle to facilitate joint movement
- Provides support
What are the types of bone?
- Long
- Irregular
- Sesamoid
- Short
- Flat
Example of an irregular bone
Vertebrae
Example of long bone
Femur
Example of sesamoid bone
Patella
Example of short bone
Ankles and wrists
Example of a flat bone
Scapula
What are growth plates most commonly located?
Metaphysis
What is yellow marrow ?
Adipose tissue
What is endosteum?
Tissue that lines the medullary cavity
What is periosteum?
A membrane of connective tissue that covers the outside of all bones
Diaphysis
The shaft (middle part) of a long bone
What are trabeculae?
Thin columns and plates of bone that create a spongy structure
Features of spongy bone
Strong, but minimises weight so that bones aren’t too heavy, limiting movement
How are trabeculae organised ?
They are aligned along principle lines of stress
What is Wolff’s law?
Bone adapts itself according to the load it is experiencing
What are osteoblasts? And where are they found?
Immature bone cells found on bone surfaces (periosteum and endosteum)
What do osteoblasts do?
Secrete organic bone matrix
What are osteoclasts ? Where are osteoclasts found?
They are multinucleate cells derived from monocytes In the endosteum
What do osteoclasts do?
Secret acids and enzymes that remove bone matrix
What are osteocytes?
Mature bone cells that are stellate
What do osteocytes do?
Petrous
Rocky
Inorganic component of bone matrix
67%
Organic component of bone matrix
33%
How many bones are in the body?
206
How many bones are we born with ?
350
What is the axial skeleton?
The central bony structure which provides protection and muscle attachment
What does the axial skeleton consist of ?
Skull, vertebral column, ribs and sternum
What is the role of the skull ?
Contains and protects the brain, organs of special sense, and upper respiratory and alimentary tracts
What are sutures ?
Fibrous joints that connect the bones of the skull
What is the role of the vertebral column ?
- Provides flexible support for the head and appendicular skeleton
- Contains and protects the spinal chord
How many pairs of ribs do we have ?
12 pairs- 7 true and 5 false
How many pairs of floating ribs do we have? What are floating ribs ?
2 pairs
They are ribs that don’t attach directly to the breastbone.
What does the appendicular skeleton consist of ?
Bones in the upper and lower limbs that support and attach the limbs to the axial skeleton
What are gomphosis ?
Fibrous joints that anchor each tooth to a socket in the jaw
What are syndesmosis ?
A fibrous joint where 2 bones are held together by ligaments
What type of joints have limited/ no movement?
Fibrous
What type of joints allow some movement to take place ?
Cartilaginous
What type of joints allow free movement ?
Synovial
What is the role of synovial fluid ?
To reduce friction during movement
What are the ends of bones at synovial joints covered with ?
Articular cartilage
