Bones Flashcards
what is known as a mineralized dense connective tissue
bone
how much of your body consists of bone?
30-40%
what is also known as the framework of the body?
bone
what are the 6 different functions of Bones?
- framework for body 2. attachment for muscles and tendons 3. allows movement in body parts 4. protects organs 5. hematopoiesis (production of blood) 5. reservoir of minerals and fat
bone forms from what two embryological sources?
- embryonic mesodermal cells 2. neural crest cells
what is known as the primordial for all the different types of cells?
mesenchyme
what are the four outer parts of the bone
-epiphysis -diaphysis -metaphysis -epiphyseal plate
what is known as the secondary center of bone?
epiphysis
what is the strongest part of the bone? also known as the primary center.
On the picture below indicate which arrow is pointing to the diaphysis!
diaphysis
The two arrows in the middle are pointing to the diaphysis!
What are the epiphysial ends of the diaphysis?
Metaphysis
what does the epiphyseal plate seperate?
the epiphysis and the metaphysis
The arrow in this picture is pointing to what?
the medullary cavity of the bone
what is the medullary cavity filled with in adults?
yellow marrow
the medulalry cavity is lined with what?
endosteum
primary ossification happens when
before birth
secondary ossificaiton happens when
after birth
where in the body is the last ossification center last to fuse?
the Fibula
when there is a lng bone with a single epiphysis that specific epiphysis is usually what?
the moveable part
the larger the epiphysis the earlier ….. what appears earleir?
the ossification center appears earleir in long bone
when does growth of a bone cease?
when the epiphysis fuses with the diaphysis
how much earleir does fusion of bones ( epiphysis and diaphyisis coming together) happen in women ?
happens 1 year earlier in women then in men
what are the 2 arteries that supply blood to the bones?
- nutrient artery
- periosteal artery
what supplies the medullary cavity and the inner 2/3rd of the cortec and metaphysis
nutrient artery
which artery enters the Volkmann’s Canal and also supplies 1/3rd of the cortex?
periosteal arteries
In regards to the picture below, the periosteal arteries are embedded in what? The nutrient arteries travel through what?
periosteal arteries are embedded in the periosteum
the nutient arteres travel through the nutrient foramen and pass through the compact bone
the axial skeleton is comprised of how many bones?
80
the appendicular skeleton is comprised of how many bones?
126 bones
what are the two types of bone components?
- compact bone
- spongy(cancellous or trabecular) bone
Bone development abnormalities can lead to problems witht the formation of bones, what is one common bone developmnent abnormality mentioned in class
achondroplasia
What is known as a condition that primarily affects the development of the bones and teeth. Peopel with this condition usually have undeveloped or absent clavicles.
Cleidocranial Syndrome (a form of bone development abnormality)
What are the seven different shapes of bone?
- long bone
- short bone
- flat bone
- irregular bone
- seasmoid bone
- pneumatic bone
- accessory bone
osteogenic cells develop into what?
osteoblasts form what?
osteocyte maintains what?
osteoclast functions in what?
- develops into an osteoblast
- forms bone tissue
- maintains bone tissue
- destroys bone matrix
wha are mature bone cells that are found in lacunae and are connected by canaliculi?
osteocytes
what is responsibe for osteogenesis(formation of bone)?
osteoblasts
what is responsible for osteolysis(destruction of bone)?
osteoclasts
what cells differentiate into osteoblasts?
osteoprogenitor cells
This is just for your information:)
What are roughly cylindrical structures that are typically several millimeters long and around 0.2mm in diameter and are important to compact bone?
osteon
the portion that the line is pointing too represents the spave for what that is inbetween trabeculae.
the space for the bone marrow
which kind of bone is located where stress are limities in ONE direction
compact bone
which kind of bone is located where stresses are weaker or multi-directional?
spongy bone
what is known as the supericfical bone except for in the joint cavities?
periosteum
the periosteum has perforating fibers called?
Sharpey’s fibers
what is known as a particiapnt in bone growth and repair
periostem
what is known to line the marroe cavity?
endosteum
what is the shallw groove fromed by the osteoclasts?
howship’s lacunae
the ground substance in bone is made up of what 4 thing?
- innorganic minerls and organic matrix (35% is organic matrix)
- collegen type 1
- GAG’s
- proteoglycans
- osteonectin
- osteocalcin
what has a larger border made out of CA++, PO4– and OH-
inorganic compound (which makes up 65%)
how much water does the living bone contain?
20%
what does inorganic content give to the bone
ridgidity
what does organic content give the bone
elasticity
lack of inorganic content causes?
lack of organic content causes?
- soft bone
- brittle bone
What is known as brittle bone disease and osteogenesis imperfecta, is a condition in which an individual’s bones become very fragile.
Lobstein Syndrome
bones form directly from what
mesenchymal sheath
Intramembranous ossification is the direct laying down of bone into the ?
the primitive connective tissue (mesenchyme)
What are the steps of ossification
- center of ossification develops
- osteocytes deposit mineral salts (CALCIFICATION)
- the trabeculae form
- the periosteum, spongy and compact bone tissue develops
what kind of ossicification do most bones form by?
endochondral ossification
what are the steps of endochondral ossification?
chondrocytes enlarge within calcifying matirx
bone formation occurs
blood vessel gets trapped in trabeculae
a marrow cavity is created
capilliaries and osteblasts migrate into the epiphysis(making secondary ossiciation centers
then the epiphysis fills with spongy bone
