Question 5. Review the mechanisms of endochondral ossification and discuss why endochondral
vs intramemebranous in long bone? Also discuss two mutations that impact on normal bone
development and remodeling.
Ossification is the process of bone formation l
The epiphyses ossify.
Calcification of the epiphyses begins at different ages for different bones. This process begins in
the secondary ossification centers and spreads throughout the hyaline cartilage matrix-except for
A thin, superficial rim
A periosteal bud, consisting of blood vessels, lymph vessels, and nerves, invades the
cavity left by the chondrocytes. Hemopoietic cells and osteoblasts inside the cavity then forms
bone marrow and blood vessels. Osteoblasts begin to secrete osteoid, form
Removal of calcified cartilage debris is believed to be accomplished by chondroclasts, large
multinucleated cells with the capacity to enzymatically degrade the dead cartilage matrix.
At the same time changes are occurring at the surface of the cartilage,
The vertebral column ( protect spinal cord) replaces the notochord
Neural arch protects neural tube
Neural spine attaches to muscle
Hemal arch and spine enclose central blood vessels
Amphicoelous concave on both sides (centrum of dogfish)
Another mutation that affects bone remodeling, the process through which
vertebrates renew bone tissue in adulthood where osteoclasts resorb bone and then
osteoblasts replace resorbed bone, is that of the gene c-src. When mice is deficient in
Striated Muscles include both skeletal and cardiac muscles. Skeletal muscles are
attached to the skeleton and used for movement, by applying force to bones and joints,
via contraction. They are responsible for voluntary movements and are innervated by the
Compare and contrast the structure, function, and regulation of striated and
smooth muscle. Include the advantages of each specific muscle type relative
to biological function. Include a pathology for each muscle that impacts
function and regulation.
Oral papillae extend into oral cavity
Transverse muscle attached to cartilaginous supports of pharynx, can compress cavity
by contracting and drive water out
Velum drive water into pharynx and prevent water from r