Card Set Information
contain no blood vessels or nerves
surrounded by the perichondrium (dense irregular connective tissue)
types of skeletal cartilage
hyaline, elastic, and fibrocartilage
functions of bones
support, protection, movement, mineral storage, blood cell formation
dense outer layer
honeycomb of trabeculae with red bone marrow
longer than wide
thin flattened, and a bit curved
ways to classify bones
flat, long, short, and irregular
one end of a long bone (head)
over joint surfaces acts as friction reducer and shock absorber
how bones "growth"
bones are highly what?
periosteum and endosteum
double layered protective membrane
inner osteogeneic layer
part of periosteum membrane
where osteoblast and osteoclast are
delicate membrane covering internal surfaces of bone
the remodel bones
location of hematopoietic tissue?
in infants-medullary cavity anf all areas of spongy bone
in adults- flat bones, vertabrae, sternum, pelvis, and the head of femur and humerus
what is hematopoietic tissue?
mature bone cells
small cavities that contain osteocytes
interconnect lacunae to each other and the central canal
the structural single unit of compact bone
tubes composed mainly of collagen
harversian or central canal
central channel containing blood vessels and nerves
channels lying at right angles to the central canal
large cells that resorb or break down bone matrix from fused monocytes
distinctive extra cellular matrix that iniciates bone formation
osteogenesis and ossification
the process of bone tissue formation (fully mineralized) hard
formation of mature bone cells is organized around what?
bone develops from a fibrous membrane (flat cranial bones)
bone forms by replacing hyaline cartilage (long bones)
steps in intramembranosus ossification?
(to make flat bones)
1. develop ossification center
2. calcification; formation of bone spicules
3. formation of woven bone (trabeculae)
4. development of periosteum and compact bone collar
begins in the second month
process of making long bones
uses hyaline cartilage as a model to form the new one
what initiates endochondral ossification?
the conversion of perichondrium to vascularized periosteum
endochondiral bone ossification steps?
1.develop and growth of cartilage bone
2. formation of bone collar and deterioration of medullary cartilage
3. development of the primary ossification center
4. development of medullary cavity
5. development of the secondary ossification center
6. formation of articular cartilage and epiphyseal plate
middle of bone where bone marrow is
hyaline cartilage on epiphyseal side of plate
where chondrocytes will pull the head away from shaft
older cells enlarge, the matrix becomes calcified, cartilage cells die and the matrix begins to deteriorate
new bone formation occurs
lysosomes are made out of what?
membrane is made of what?
osteoblast and osteoclasts deposit and resorb bone at the periosteal and endosteal surfces
with help from lysosomes
what stimulates bone growth?
what controls the remodeling of bone?
hormones that controls calcium in blood
mechanical and gravitational forces acting on the skeleton
what is calcium necessary for?
transmission of nerve impulses
secretion by glands and nerve cells
raising Ca triggers the release of calcitonin (hormone)
calcitonin stimulates calcium salts deposit in bone
falling Ca signal the release of PTH
PTH signals osteoclasts to degrade bone matrix for release Ca into the blood
osteons go in the direction of what?
group of diseases in which bi=one reabsorption outspaces bone deposit (taking out of Ca is faster than it can be put back in)
happens most in postmenopausal women
bones are inadequately mineralized causing softened weakened bones
cause by insufficient Ca or Vitamin D