Skeletal System Flashcards
What are the 4 reasons why bones are considered living tissues?
- They have blood and lymphatic vessels and nerves
- They are subject to disease
- They undergo turnover (cell creation and destruction)
- They adjust to changes in stress
What type of tissue is bone?
Connective
What are the four primary functions of bone?
- Structural and organizational support for the body
- Protection of sensitive organs
- Blood cell production (in the bone marrow)
- Storage for important minerals (Calcium and Phosphorus)
What are the two primary types of bone?
Compact/cortical and spongy/cancellous
What is compact/cortical bone?
The hard layer on the exterior of bone that forms the shaft of long bones
What is cancellous/spongy bone?
Spicules arranged in a porous network that is filled with marrow
What is the medullary/marrow cavity?
A space surrounded by cortical bone that creates blood cells and releases calcium quickly
What type of marrow fills the medullary cavity in young and old animals and what does each do?
Young animals- red marrow made of hematopoietic tissue, which produces blood cells
Old animals- yellow marrow made of fat
Parts of gross bone from top to bottom (immature)
Articular cartilage, proximal epiphysis, epiphyseal cartilage, metaphysis, diaphysis, metaphysis, epiphyseal cartilage, distal epiphysis, articular cartilage
Parts of gross bone from top to bottom (mature)
Articular cartilage, metaphysis (epiphysis included?), diaphysis (within is medullary cavity), metaphysis (epiphysis included?), articular cartilage
What is the epiphysis and what are the two types?
Either end of a long bone
1.) Proximal epiphysis is the end closest to the body
2.) Distal epiphysis is the end farthest from the body
What is the diaphysis?
The cylindrical shaft of the long bone between the two epiphyses
What is the metaphysis?
The flared are of a mature bone that is adjacent to the epiphysis
What is the epiphyseal cartilage/disk
A layer of hyaline cartilage in the metaphysis of an immature bone that allows the bone to lengthen
What is articular cartilage?
A thin layer of hyaline cartilage that covers the joint surface of a bone
What is the periosteum?
A fibrous membrane that covers the surface of a bone, except where there is articular cartilage
What are osteoblasts?
Bone-producing cells
What is the main function of periosteal osteoblasts?
To increase bone diameter and heal fractures
What are 2 features of the periosteum?
Vascular and well-innervated
What is the endosteum?
A fibrous membrane that covers the medullary cavity and the osteons of a bone
What are osteoclasts?
Bone-destroying cells
What is the main function of endosteal osteoclasts?
Determine the size of the medullary cavity and the thickness of the diaphyseal cortex (cortical bone)
What are projections?
Protrusions above the surface
What are depressions?
Low areas/indentations
What does articular mean?
Relating to joints or areas of the bone covered by articular cartilage
What does non-articular mean?
Not related to joints or articular cartilage
