MM and NN Tissue Flashcards
Striated m.
possess striations
includes cardiac and skeletal
both can be trained
Skeletal m.
striated strong quick voluntary can fatigue multinucleated (peripheral) very large cells (myotube)
Cardiac m.
striated strong quick incoluntary must NEVER fatigue uninucleated (central) branched cells separated by intercalated discs
Smooth m.
not striated weaker slow and often rhythmic involuntary uninucleated (long, central) fusiform cell shape very different arrangement of contractile elements
Cardiac m. fibers
involuntary
spiral arrangment
insert into fibrous cardiac skeleton
longitudinal portion of the intercallated discs are where all of the gap junctions are located to allow ionic comm. b/w cells which leads to synchronous mm contraction
Smooth m. Microstructure
slow involuntary lines the walls of hollow organs controls how wide or narrow their lumens become short, spindle shaped cells central cigar shaped nucleus mitochondria caveolae
Caveola
seen in smooth mm.
under plasma membrane of 2 adjacent smooth mm cells
act as the sarcoplasmic reticulum
Contractie elements
smooth m.
mostly under the cell membrane and tighten to cntract the cell itself
Schwann cell
makes myelin which wraps around the neuron and speeds up the electrical signal (PNS)
only myelinates one axon
oligodendrocytes
makes the myelin sheath in CNS
can myelintate multiple axons
nodes of Ranvier
gaps between schwann cells
endoneurium
allows capillaries to run amoun the n. fibers
multipopar neurons
motor neuron
pyramidal neuron
purkinje cell
many dendrites out of the cell body
bipolar neurons
retinal neuron
olfactory neuron
only one dendrite
unipolar neuron
touch and pain sensory neuron
dendrites not out of cell body
