Chapter 6 - Bone Flashcards
What is the center of an osteon that contains the blood vessels called?
Central Canal
What is the branching canals pervading the matrix for diffusion of materials between blood and osteocytes called?
Canaliculi
What are bone cells and where do they reside?
Osteocytes ; Lacunae
What are typically organized around blood vessels, separated by layers of matrix, and oriented along the main axis of the bone?
osteon
What is the outter sheath containing fibrous and cellular layers?
Periosteum
In the periosteum, the fibrous (outer) layer does what?
It attaches bone to adjacent tissues, tendons and ligaments
In the periosteum, the cellular (inner) layer is important for what reasons?
It’s important for appositional growth of the bone and its repair after injury
What is bone?
A strong, somewhat flexible tissue. It undergoes extensive remodeling throughout life
What is the bone matrix comprised of?
Little ground substance, 2/3 calcium salts, calcium phosphate (predominantly), calcium carbonate (secondarily), and collagen fibers
How many bones are in the adult human body?
206 bones
What are the 5 functions of the skeleton?
Support, mineral/lipid storage, blood cell production, protection, and leverage
What skeleton function is the structure for the entire body and attachment points for soft tissues and organs?
Support
What is the purpose of mineral/lipid storage for skeletal function?
It maintains blood calcium (most abundant mineral in the body) and phosphate levels
As far as skeletal functions, what does bone produce and where?
Red blood cells, leukocytes, and platelets are produced in red bone marrow
How does the bone protect regarding skeletal functions?
It surrounds delicate tissues/organs
Bone/joints act as _______ to change the magnitude direction of force?
levers
Thin, roughly parallel surfaces that protect underlying soft tissues.
Flat bones
Irregular bones formed between cranial bones. (hint= wormian bones)
Sutural bones
Bones that are mostly found in the limbs.
long bones
Bones with complex shapes with short, flat, notched, or ridged surfaces.
Irregular bones
Bones that are small, flat and that develop inside tendons of knees, hands and feet. (Hint= shaped like sesame seeds)
Sesamoid bones
Small and boxy bone. (wrist, and ankles)
Short bones
The proximal end of a bone that forms part of a joint.
Head of the bone
The narrow connection between the head and the diaphysis.
Neck of the bone
The elongated body of a bone.
Diaphysis (shaft)
What are the 6 classifications of bone based on shape?
flat bones, sutural bones, long bones, irregular bones, sesamoid bones, and short bones
This part of long bone consists largely of spongy bone?
Epiphysis
Connects epiphysis to shaft (diaphysis)
Metaphysis
Involved in red blood cell production
Red marrow
What type of marrow is adipose tissue?
Yellow marrow
What are the 7 steps in endochondral ossification?
- Cartilage model enlarges
- Blood vessels grow around edge of the cartilage model
- Blood vessels penetrate cartilage and enter central region
- Growth continues along with remodeling
- Capillaries and osteoblasts migrate into the epiphyses
- Epiphyses fill with spongy bone
- Bone grows in length at the epiphyseal cartilage
What are the 4 cell types of bone tissue?
Osteocytes, osteoblasts, osteogenic cells, and osteoclasts
The overall function of osteoclasts is to ________?
Break down bone matrix
The function of osteoblasts is to ________?
To produce new boney matrix
What is the process of creating new bone?
starts with the release of proteins that produce un-mineralized matrix (osteoid) then calcium salts convert osteoid to bone.
Where are mesenchymal cells important?
In fracture repair
What is the function of the osteoclasts and what is the process called by which they perform that job?
To dissolve boney matrix in a process called osteolysis.
The functional unit of compact bone is ____?
Osteon
What does appositional bone growth do?
It increases the diameter of pre-existing bone ; does not form original bones
The incomplete cellular layer lining medullary cavity and action during bone growth repair and remodeling
Endosteum
The importance of calcium in the body (physiologically speaking)
Muscle contractions, blood coagulation, nerve impulse generation.
How does the body maintain calcium levels
Absorbs calcium and phosphate in the intestines, osteoclasts release calcium, osteoblasts use calcium. and calcium is released in urine.
