Bones
This is 1/3 of organic bone matrix secreted by osteoblasts
osteoid
longitudinal growth of the bone is called
Interstitial growth
When bone are poorly mineralized so bones end up soft and weak, its called what?
Osteomalcia
How many paired spinal nerves are in the PNS?
31 pairs
What is resting membrane potential?
These cells are "bone breakers" and have ruffled edges
Osteoclasts
widening of the bone is called what
appositional growth
When bone resorption exceeds bone deposit it's called?
(matrix remains normal but bone mass declines)
Osteoporosis
Is sensory division afferent or efferent?
afferent
What are the 3 types of gated channels
Chemically gated (ligand gated), voltage gated, mechanically gated
When the diaphysis elongates and a medullary cavity is formed. What is the name for the medullary cavity?
Primary Ossification Center (POC)
how often is compact bone replaced?
10 years
This disease has excessive and haphazard bone deposit and resorption causing bones to be made fast and poorly.
Pagets
Which division of the PNS is voluntary?
Motor division
What happens at +30?
Na+ gates close, AP stops spiking, VG K+ channels open
What percentage of bones are made through endochondral ossification
90%
this condition in children results in bowed legs and other bone deformities
Ricket's
Explain hyperpolarization and why could it be a bad thing?
an increase in membrane potential away from zero (more negative)
It could be bad because it reduces the probability of producing a nerve impulse
Which sub-category of the ANS is responsible for fight or flight?
sympathetic divison
What is an IPSP
Inhibitory Postsynaptic Potential- a local hyperpolarization of the postsynaptic membrane (drives the neuron away from AP threshold)
whats is the other name for the "growth plate?"
Epiphyseal plate
This states that bones grow or remodel in response to demands placed on them
Wolff's Law
What could lead to hyperpolorization?
an influx of - ions (maybe Cl-)
Neuroglia that are oligodendrocytes have what special feature and can also be called what?
myelin wrapping/sheath and can be called Schwann cells
A single EPSP CANNOT induce an AP... so what has to happen in order for an EPSP to induce an AP?
summation