Dr. Olinger's Muscle and Nerve Tissue lecture Flashcards
Striated muscle can contain
skeletal and cardiac muscle
The differences between skeletal and cardiac muscle tissue
Skeletal:
multinucleated (peripheral)
voluntary
fatigues
Cardiac
uninucleated (central) nonvoluntary does not fatigue Separated by intercalated discs branched
Smooth muscle
not striated weaker than striated slow and often rhythmic Involuntary Uninucleated (long central) Fusiform cell shape different arrangement of contractile elements
Cardiac muscle fibers are inserted into a
fibrous cardiac skeleton
what kind of arrangement are cardiac muscles?
spiral
What do we expect to find in the intercalated discs?
Gap junctions that allow for ionic communication between cells which leads to synchronous muscle contraction
so what’s the BIG thing that intercalated discs are known for?
possessing GAP junctions which allow for ionic flow between cells in order to produce synchronous action
a short “cigar shaped” nucleus would indicate the cell is a
smooth muscle cell
you encounter a “spindle shaped cell” which would indicate the cell is a
smooth muscle cell
Caveolae = “……”
little caves
where are caveolae found?
under the plasma membranes of 2 adjacent smooth muscle cells
what do caveolae do?
act as the sarcoplasmic reticulum
where in the membrane (inside or outside) would contractile elements be found?
in the inside, and tighten to contract the cell itself
what are in the contractile fibers, and what are the supporting fibers?
they contain actin and myosin
supporting fibers = intermediate filaments
Perikaryon =
cell body of the neuron
nissl substance is located
in the cell neuron
nissl bodies =
hese granules are of rough endoplasmic reticulum (RER) with rosettes of free ribosomes, and are the site of protein synthesis.[wiki)
Would you find a nissl body in the axon?
no
Highly branched–almost choral appearing–neuron =
golgi type II neuron
short axons would be found on
golgi type II neurons
long axons would be found on
type I neurons
highly branching dendrites would be found on
golgi type II neurons
very unbranching dendrites would be found on
golgi type I neurons
Multipolar neurons include
motor neurons, purkenji neurons, pyramidal neurons
Bipolar neurons would include
retinal and olfactory neurons
unipolar neurons would include
touch and pain sensory neurons
anaxonic neurons is a
amacrine cell
A peripheral never us surrounded by an
epineurium
fill in the blanks
an axon is covered by \_\_\_\_ which is surrounded by an which is contained in a \_\_\_\_\_\_ which is surrounded by a \_\_\_\_\_\_\_\_\_ which is found in a \_\_\_\_\_\_\_ covered by \_\_\_\_\_\_
myelin sheaths formed by neurolemma or Schwann Cells
endoneurium
fascicle with other neuron fibers
perineurium
peripheral nerve
epineurium
where would the vasa nevorum be located: epineurium, perineurium, or endoneurium?
epineurium
Schwann cells
myelin producing cells of the PNS, clinical name is neurolemma
Neurolemmas vs oligodendrocytes
Neurolemma are found in the PNS
oligodendrocytes are found in the CNS
oligodendrocytes
myelin producing cells of the CNS which are capable of myelinating multiple axons
How do Schwann cells achieve their effect?
They wrap around a peripheral axon many times and SQUEEZE out the cytoplasm, leaving multiple layers of lipid rich trilaminar membrane
Nissl substance is found where….and where ISNT it located
Nissl isn’t located at the AXON: so if you want to know where the AXON on is, you will look for where there is an absence of nissl
an absence of nissl in the cell body indicates
the axon hillock
A motor end plate is found adjacent to what kind of macrostructure?
muscle
what Golgi type would a neuron without an axon be?
Golgi type II
What does a conduction signal through a unipolar (psuedopolar) neuron NOT have to deal with as much as a signal through a bipolar neuron?
it doesnt have to ramify through cell body as much
a bunch of endoneurium wrapped axons in bundles surrounded by a perineurium is called a
fascicle
a peripheral fiber is an
a myelinated, endoneirum wrapped axon
a peripheral nerve is a
perinerium wrapped bundle of fascicles
what is the main difference between a Scwann cell and an oligodendrocyte (apart from the CNS/PNS binary)
Schwann cells can only myelinate one axon, oligo’s can myelinate multiple axons
does the Schwann cell secrete myelin or what?
it’s the cell membrane of schwann cell itself that IS the myelin, it doesn’t secrete anything
