The Skeletal System Flashcards
What are the functions of the skeletal system?
Structural support, protects internal organs, provides leverage for movement, stores calcium and produces blood cells.
Bone is a specialised form of what kind of tissue?
Connective tissue
What cells are found in the bones?
Osteoblasts, osteocytes, osteoclasts and osteogenic stem cells
What do osteoblasts do?
Produce new bone, secrete osteoid and are responsible for mineral deposition
What are osteocytes?
Mature bone cells located in lacunae. They maintain the matrix
What do osteoclasts do?
Remove mineral from the matrix, responsible for bone remodelling
Where osteogenic stem cells found are and what do they become?
Found in periostem and endosteum. They develop into osteoblasts
What are the two tissue types that make up bones?
Compact bone and cancellous (spongy) bone
What is the basic functional unit of compact bone called?
The osteon – they are structured to resist stress. If you think of a plastic straw, one on its own if you tried to compress would easily break but if you had lots of straws together it would be harder to compress
In cancellous bone there are spaces between the trabeculae, what is in the spaces?
Bone marrow
What is the difference between red bone marrow and yellow bone marrow?
Red bone marrow is myeloid tissue that is haemopoietic (produces RBC’s) and yellow bone marrow is fatty tissue that no longer produces blood.
What are the 4 main classifications of bones by shape?
Long bones, short bones, flat bones and irregular bones.
Definition of a long bone
Longer than they are wide. Act as levers.
Definition of short bones
Nearly equal in length and width. Glide over each other e.g. wrist bones, carpals and tarsals
Definition of a flat bone
Protect organs and serve for muscle attachment e.g cranial bones and sternum
