Muscular System Flashcards
identify
function:
- body movement
[muscle tissues]
skeletal muscle
identify
An action potential that was produced at the neuromuscular junction is propagated along the (?) of the skeletal muscle.
The depolarization also spreads along the membrane of the (?)
[muscle contraction]
- sarcolemma
- T tubules
identify
Each sarcomere consists of an (?) and (?)
[muscle proteins]
- actin filament
- myosin myofilament
identify
Choline is symported with Na+ into the (?), where it can be recycled to make ACh.
(?) diffuses away from the synaptic cleft
[neuromuscular junction]
- presynaptic terminal
- acetic acid
identify what step this is
Calcium ions enter the presynaptic terminal and initiate the release of the neurotransmitter acetylcholine (ACh) from synaptic vesicles
[neuromuscular junction]
step 2
identify
the length of the muscle does not change but the amount of tension increases during contraction
[types of muscle contractions]
isometric contractions
identify
the plasma membrane is more permeable to (?) than to (?)
[resting membrane potential]
- K+
- Na+
identify
action potentials in the communicating neuron stimulate graded potentials in a recieving neuron than can summate at the (?)
[action potential propagation]
trigger zone
identify
composed of 2 heavy chains wounded together and 2 light chains on each heads of the heavy chain
[myofilaments|thick]
myosin
identify
has striations
[muscle tissues]
- skeletal muscle
- cardiac muscle
identify
location of Skeletal Muscle
attached to bones
identify
seven (7) major function of muscles
- movement of the body
- maintenance of posture
- respiration
- production of body heat
- communication
- constriction of organs and vessel
- contraction of the heart
identify
failure of the muscle to relax after a forceful contraction
[muscle conditions]
Myotonic muscular dystrophy
identify
Multinucleated, immature muscle fibers (myocytes).
[muscle development]
myoblasts
identify
nucleus:
- single, centrally located
[muscle tissues]
- smooth muscle
- cardiac muscle
identify what step this is
ACh unbinds from the ligand-gated Na+ channels, which then close
[neuromuscular junction]
step 6
identify
cylindrical and branched
(100-500 μm in length, 12-20 μm in diameter)
[muscle tissues]
cardiac muscle
identify
Each sarcomere consists of an actin myofilament and myosin myofilament.
The middle-most region is called the (?) that is found within the (?) all enclosed inside the (?) which is found between two (?)
[muscle proteins]
- M line
- H zone
- A band
- I band
identify what step this is
An action potential arrives at the presynaptic terminal and causes voltage-gated Ca2+ channels in the presynaptic membrane to open
[neuromuscular junction]
step 1
identify
The enzyme acetylcholinesterase, which is attached to the postsynaptic membrane, removes acetylcholine from the (?) by breaking it down into (?) and (?)
[neuromuscular junction]
- synaptic cleft
- acetic acid, choline
identify
amount of tension produced by the muscle is constant during contraction but the length of the muscle changes
[types of muscle contractions]
isotonic contractions
identify
ability of muscle to spring back to its original resting length after it has been stretched
[functional properties of muscles]
elasticity
identify
function:
* pumping blood
[muscle tissues]
cardiac muscle
identify
acetylcholine (ACh) unbinds from the (?), which then close
[neuromuscular junction]
ligand-gated Na+ channels
identify
Heavy chains connect each end of the (?)
[myofilaments|thick]
sarcomere
identify
capacity of muscle to respond to an electrical stimulus via nervous or hormones
[functional properties of muscles]
excitability
identify
has active sites responsible for the formation of cross-bridge with the myosin light chains
[myofilaments|thin]
fibrous actin (F-actin)
identify
An action potential arrives at the (?) and causes voltage-gated Ca2+ channels in the presynaptic membrane to open
[neuromuscular junction]
presynaptic terminal
identify
nucleus:
- multiple nuclei, peripherally located
[muscle tissues]
skeletal muscle
identify
(?) enter the presynaptic terminal and initiate the release of the neurotransmitter acetylcholine (ACh) from synaptic vesicles
[neuromuscular junction]
calcium ions
identify what step this is
Ligand-gated Na+ channels open and Na+ enters the postsynaptic cell, causing the postsynaptic membrane to depolarize.
If depolarization passes threshold, an action potential is generated along the postsynaptic membrane
[neuromuscular junction]
step 5
identify
the constant tension produced by muscles for long periods of time
[types of muscle contractions]
muscle tone
identify
special cell-to-cell attachements:
- none
[muscle tissues]
skeletal muscle
identify
location of Smooth Muscle
walls of:
- hollow organs
- blood vessels
- eyes
- glands
- skin
identify
“myalgia”; idiopathic
[muscle conditions]
chronic muscle pain syndrome
identify
Accumulates contractile proteins in the cytoplasm to develop into mature cell
[muscle development]
myoblasts
identify
occurs due to muscle disuse
[muscle conditions]
atrophy
identify
isotonic contractions in which tension is maintained in a muscle, but the opposing resistance is great enough to cause the muscle to increase in length
[isotonic contractions]
eccentric
identify
isotonic contractions in which tension in the muscle is great enough to overcome the opposing resistance, and the muscle shortens
[isotonic contractions]
concentric
identify
Light chains interacts with the active sites of the (?)
[myofilaments|thick]
Fibrous actin (F actin)
identify
two (2) types of isotonic contractions
- concentric
- eccentric
identify
not capable of spontaneous contraction
[muscle tissues]
skeletal muscle
identify
overuse of skeletal muscle
[muscle conditions]
tendinitis
identify what step this is
Choline is symported with Na+ into the presynaptic terminal, where it can be recycled to make ACh.
Acetic acid diffuses away from the synaptic cleft
[neuromuscular junction]
step 8
identify
very long and cylindrical
(1 mm-4 cm, or as much as 30 cm, in length, 10 μm-100 μm in diameter)
[muscle tissues]
skeletal muscle
identify
group of genetic disorders of muscle degeneration
[muscle conditions]
dystrophy
identify
three (3) subunits of troponin
[myofilaments|thin]
- troponin I (TnI)
- troponin C (TnC)
- troponin T (TnT)
identify
hides the active sites of F actin molecules
[myofilaments|thin]
tropomyosin
identify
autoimmune disease that competes with acetylcholine
[muscle conditions]
myasthenia gravis
identify
spindel-shaped
(15-200 μm in length, 5-8 μm in diameter)
[muscle tissues]
smooth muscle
identify
deposition of connective tissue
[muscle conditions]
fibrosis
identify what step this is
ACh is released into the synaptic cleft by exocytosis
[neuromuscular junction]
step 3
identify
charge difference across the plasma membrane of an unstimulated cell. Produces the action potential
[action potential & resting membrane potential]
resting membrane potential
identify
alteration of genes that code for dystrophin
[muscle conditions]
Duchenne-type muscular dystrophy
identify
electrical signal travelling from the brain, passes through the spinal cord, then to the muscle fibers causing them to contract. Requires resting membrane potential
[action potential & resting membrane potential]
action potential
identify
Ligand-gated Na+ channels open and Na+ enters the (?), causing the (?) to depolarize
[neuromuscular junction]
- postsynaptic cell
- postsynaptic membrane
identify
function:
- moving food through digestrive tract
- emptying the urinary bladder
- regulating blood vessel diameter
- changing pupil size
- contracting many gland ducts
- moving hair
[muscle tissues]
smooth muscle
identify
Mature cells that make up the functional unit of the
muscular system
[muscle development]
muscle fibers
identify
acetylcholine (ACh) diffuses across the (?) and binds to ligand-gated Na+ channels on the (?)
[neuromuscular junction]
- synaptic cleft
- postsynaptic membrane
identify
Once active sites on G actin molecules are exposed, the heads of the (?) bind to them to form (?)
[muscle contraction]
- myosin myofilaments
- cross-bridges
identify
the functional unit of the muscular system
[muscle development]
sarcomere
identify
location of Cardiac Muscle
heart
identify
acetylcholine (ACh) is released into the synaptic cleft by (?)
[neuromuscular junction]
exocytosis
identify
the concentration of (?) outside the plasma membrane is higher than that inside the plasma membrane
[resting membrane potential]
Na+ (sodium ion)
identify
The depolarization of the T tubule causes (?) in the sarcoplasmic reticulum to open, resulting in an increase in the permeability of the sarcoplasmic reticulum to Ca2+, especially in the terminal cisternae.
Calcium ions then diffuse from the (?) into the (?)
[muscle contraction]
- voltage-gated Ca+2 channels
- sarcoplasmic reticulum
- sarcoplasm
identify
mononucleated cells that fuse together to form a myoblast
[muscle development]
myoblast precursor cells
identify
action potentials are propagated down the (?) to the (?)
[action potential propagation]
- axon
- axon terminal
identify
muscle can be stretched beyond its normal resting length and still be able to contract
[functional properties of muscles]
extensibility
identify
binds to actin
[troponin]
troponin I (TnI)
identify
prolonged skeletal muscle tension
[muscle conditions]
fibrositis
identify what step this is
ACh is re-formed within the presynaptic terminal using acetic acid generated from metabolism and from choline recycled from the synaptic cleft.
ACh is then taken up by synaptic vesicles
[neuromuscular junction]
step 9
identify
three (3) types of muscle contractions
- isometric contractions
- isotonic contractions
- muscle tone
identify
involuntary control
[muscle tissues]
- smooth muscle
- cardiac muscle
identify what step this is
ACh diffuses across the synaptic cleft and binds to ligand-gated Na+ channels on the postsynaptic membrane
[neuromuscular junction]
step 4
identify
dehydration and ion imbalance
[muscle conditions]
cramps
identify
The concentration of (?) inside the plasma membrane is higher than that outside the plasma membrane,
[resting membrane potential]
K+ (potassium cation)
identify
special cell-to-cell attachments:
- gap junctions
[muscle tissues]
smooth muscle
identify
no striations
[muscle tissues]
smooth muscle
identify
two (2) types of muscular dystrophy
[muscle conditions]
- Duchenne-type muscular dystrophy
- Myotonic muscular dystrophy
identify
special cell-to-cell attachements:
- intercalated disks join cells to one another
[muscle tissues]
cardiac muscle
identify
binds to tropomysin
[troponin]
troponin T (TnT)
identify
ACh is re-formed within the (?) using (?) generated from metabolism and from choline recycled from the synaptic cleft.
ACh is then taken up by synaptic vesicles
[neuromuscular junction]
- presynaptic terminal
- acetic acid
identify
normal in skeletal muscles; abnormal in cardiac muscles
[muscle conditions]
hypertrophy
identify what step this is
The enzyme acetylcholinesterase, which is attached to the postsynaptic membrane, removes acetylcholine from the synaptic cleft by breaking it down into acetic acid and choline
[neuromuscular junction]
step 7
identify
Calcium ions released from the sarcoplasmic reticulum bind to (?)
The troponin molecules bound to G actin molecules are released, causing tropomyosin to move, and to expose the active sites on (?)
[muscle contraction]
- troponin molecules
- G actin
identify
three (3) types of body muscles
- smooth
- skeletal
- cardiac
identify
Each sarcomere is separated by a (?) which are seen within each I band
[muscle proteins]
Z disk
identify
ability of muscle to shorten forcefully and passively lengthens
[functional properties of muscles]
contractility
identify
Muscle fibers no longer multiply maintaining a relatively constant number after birth.
The increase in size is due to (?) in response to muscle usage
[muscle development]
hypertrophy
identify
binds to calcium
[troponin]
troponin C (TnC)
identify
voluntary and involuntary (reflexes)
[muscle tissues]
skeletal muscle
identify
capable of spontaneous contraction
[muscle tissues]
- smooth muscle (some)
- cardiac muscle
identify
Ligand-gated Na+ channels open and Na+ enters the postsynaptic cell, causing the postsynaptic membrane to depolarize.
If depolarization passes threshold, an (?) is generated along the (?)
[neuromuscular junction]
- action potential
- postsynaptic membrane
