Ch 10 Flashcards
what causes a stimulus to produce electrical signals (action potentials)?
electrical excitability
what does it mean to shorten in length?
contractible
what does it mean to extend or stretch?
extensible
what can return to it’s original shape?
elastic
what are the functions of muscular tissue?
produce body movement, stabilize, store and move substances, generate heat
what attaches to and moves bones?
skeletal muscle
what is found inside the walls of hallow organs, blood vessels, and airways?
smooth muscle
what type of muscle forms the heat wall?
cardiac muscle
what is a thick fascia that connects two muscle bellies?
aponeurosis
what runs origin to insertion?
muscle fibers = muscle cells
what is a sarcolemma?
plasma membrane
what is the sarcoplasm?
cytoplasm
what are the two types of filaments?
myosin and actin
what are thick filaments?
myosin
what are thin filaments?
actin
what is a system of membranous sacs that surround each myofibril?
sarcoplasmic reticulum
what does sarcoplasm reticulum do in relaxed muscle?
releases calcium and triggers muscle contraction
what separates sarcomeres?
Z disc
what is the line in the center of sarcomeres?
M line
what is the dark area containing thick and thin filaments?
A band
what is the light area, containing only thin filaments?
I band
what is the center of the A band that contains thick filaments only?
H zone
what filament is strung together like beads?
actin
what are thin filaments?
actin
what are thick filaments?
myosin
what filament looks like golf clubs?
myosin
what are troponin and tropomyosin?
regulatory proteins
what extent from the Z disc to the M line, accounting for elasticity in myofibrils?
titin
what stabilizes the sarcoplasmic reticulum and is deficient in muscular dystrophy?
dystrophin
what are contractile proteins?
actin and myosin
what generates force during contraction?
actin and myosin
what are troponin and tropomyosin?
regulatory proteins
what switches contraction processes off and on?
regulatory proteins
what are structural proteins?
titin and dystrophin
what keeps thick and thin filaments in proper alignment and contribute to stability, elasticity, and extensibility of myofibril?
structural proteins
what is a nerve impulse that sends an electrical signal that probates (travels) along the surface of the membrane of a neuron?
action potential
what is another name for a neuron?
nerve cell
what is a change in the cells environment strong enough to initiate it’s action potential?
stimulus
what allows specific ions to flow in and out of cells and allows resting membrane to change?
an ion specific channel
what does action potentials depend on?
resting membrane potential and ion specific channels
what is the difference in the amount of electrical charge on the inside and outside of the cell?
membrane potential
what charge are ions outside the surface of the membrane?
positive
what charge are ions inside the surface of the membrane?
negative
what is the resting membrane potential set at?
-70
there are more ____ leak channels than ____.
potassium (K+), sodium (Na+)
more ____ flows out that ____ comes in.
potassium (K+), sodium (Na+)
what does polarized mean?
more negative inside
what is a stimulus that isn’t strong enough to cause an action potential?
a graded potential
what does it mean to be less polarized?
negative membrane potential reverses (becomes positive)
what travels a short distance?
a graded action potential
what travels a long distance?
an action potential
as the strength of the stimulus ____, the amplitude ____, this depolarization ____.
increases, increases, increases
what happens when the number of stimuli increases, the amplitude increases, and depolarization increases?
summation
what is the action potential threshold?
-55mv
what occurs during the depolarizing phase?
negative membrane reverses (becomes positive)
what happens in the depolarizing phase?
the membrane potential returns to it’s original state (-70mv)
what are the two types of propagation?
continuous conduction and saltatory conduction
what kind of axons are in continuous conduction?
un-myelinated axons
what kind of axons are in saltatory conduction?
myelinated axons
which is faster: continuous conduction or saltatory condition?
saltatory conduction
what happens in the excitatory postsynaptic potential (ESPS)?
depolarization - no action
what happens in the inhibitory postsynaptic potential (ISPS)?
hyper polarization - stops action potential
what is the process in which graded potentials add together?
summation
