AP 1 muscle tissue
place the events at a neuromuscular junction in order
1. arrival of nerve signal at synaptic knob 2. calcium entry into synaptic knob 3. exocytosis of ACh into synaptic cleft 4. binding of ACh to motor end plate
enzyme that breaks down the muscle neurotransmitter
acetylcholinesterase (AChE)
match the components of a muscle fiber with its description sarcoplasm
cytoplasm of a muscle fiber
the amount of additional oxygen that must be inhaled in order to restore pre-exercise levels is called oxygen
debt
the epimysium of a muscle is composed of __ connective tissue
dense irregular
match each skeletal muscle function with its description body movement
muscles contract and pull on the tendons that attach the muscles to the bones
protein filament that provides elasticity
titin
match each function of skeletal muscle with its description storage and movement of materials
voluntary sphincter muscles of the gastrointestinal and urinary tracts can be kept closed or opened
The skeletal muscles arranged in layers along the walls of the abdominal cavity and the floor of the pelvic cavity perform what function
-contraction -compression -support -protection
a neuromuscular junction contains a(n)
-synaptic cleft -motor end plate -synaptic knob
place the following events in the correct order of occurrence once ACh diffuses across the synaptic cleft of a NMJ
1. ACh binds to receptors on the motor end plate 2. the resulting action potential moves down the sarcolemma 3. the action potential moves down the t-tubules 4. the action potential reached the terminal cisternae of the SR 5. calcium ions are released into the sarcoplasm
place the events of a neuromusclular junction in order
1. arrival of nerve signal at synaptic knob 2. calcium entry into synaptic knob 3. exocytosis of ACh into synaptic cleft 4. binding of ACh to motor end plate
place the stages of cross-bridge cycling in order
1. calcium binds troponin; myosin binding site uncovered 2. cross-bridge formation 3. power stroke 4. release of myosin head by ATP 5. reset of myosin head
The arrival of a nerve impulse at the synaptic knob of a motor neuron causes synaptic vesicles to release __ into the synaptic cleft
ACh
acetylcholinesterase in the synaptic cleft is needed so that __ will not continuously stimulate the cell to contract
ACh
thick myofilaments are composed of bundles of what protien molecule
Myosin
receptors in the motor end plate bind with the neurotransmitter __ released from the synaptic knob
acetycholine
ACh is an acronym for
acetylcholine
contraction of a muscle fiber requires myosin heads in the thick filament bind to active sites on __ molecules within the thin filaments
actin
match the duration of a single muscle contraction with the source of ATP long term
aerobic respiration
a muscle cell obtains ATP in the short term via what process
anaerobic respiration
match the duration of a single muscle contraction with the source of atp short term
anaerobic respiration
in a muscle cell, the short term energy is supplied by __ respiration, while long term energy is supplied by __
anaerobic/aerobic
the sarcoplasmic reticulum stores __ ions needed to initiate muscle contracion
calcium
the walls of the heart are composed of __ muscle
cardiac
match each skeletal muscle function with its description posture
contraction of specific muscles stabilizes joints
match the duration of a single muscle contraction with the source of ATP immediate
creatine phosphate
when the thin and thick filaments meet
cross bridge
match each muscle unit with the connective tissue layer that surrounds it muscle cell
endomysium
match each muscle unit with the connective tissue layer that surrounds it muscle
epimysium
the synaptic knob of the neuron is an __ of an axon
extended tip
the __ line is a thin, transverse, protein meshwork structure in the center of the H zone of a sarcomere
m
in a motor unit, a single __ neuron typically controls numerous muscle fibers in a muscle
motor
match the components of a muscle fiber with its description t-tubules
narrow, tubular extensions of the sarcolemma into the sarcoplasm
Aerobic respiration requires the presence of what molecule
oxygen
contractile unit of a muscle
sarcomere
within a myofibril, each __ shortens as the muscle fiber contracts
sarcomere
the motor end plate has folds and indentations to increase the membrane surface area adjacent to the
synaptic knob
where the neural transmitter is held until it is released
synaptic knob
a cord-like structure that attaches muscle to bone is a
tendon
when calcium ion bind to troponin, which of the following then occur
the myosin binding sites on actin are exposed
the H-band (or H-zone) is more lightly shaded because only __ fiaments are present
thick
the H-band (or H-zone) is more lightly shaded because only __ filaments are present
thick
under the light microscope, the dark (a) bands observed in skeletal muscle contain __ filaments
thick and thin
match the name of the muscle cell component with its function T-tubules
transports the action potential from the sarcolemma throughout the entire muscle fiber
thin filament that covers the myosin binding sites
tropomyosin
the motor neutron transmitters the effect of a nerve impulse to the muscle fiber at a neuromuscular
junction
match the name of the muscle cell component with its function muscle fiber
metabolic activities; contraction
skeletal muscle contraction is controlled by __ neurons
motor
skeletal muscle fibers are __
multinucleated
myofibrils are made of
myofilaments
thick filament
myosin
the area where the neuron and motor plate meet
neural muscular junction
match each muscle unit with the connective tissue layer that surrounds it fascicle
perimysium
ATP is generated when the enzyme creatine kinase transfers Pi from creatine __ to ADP
phosphate
match the components of a muscle fiber with its description sarcolemma
plasma membrane of a muscle fiber
match the name of the muscle cell component with its function sacrolemma
regulates entry and exit of materials
the plasma membrane of a skeletal muscle fiber is called the
sacrolemma
thick and thin filaments maintain their __, whether the muscle is relaxed or contracted
same length
a contracting skeleton muscle fiber typically shortens as all of its __ shorten in length
sarcomeres
the cytoplasm of a skeleton muscle cell is referred to as
sarcoplasm
at the end of contraction, when the stimulation from the nerve impulse ceases, calcium ions are pumped back into the __
sarcoplasmic reticulum
match the name of the muscle cell component with its function sarcoplasm
site of metabolic processes for normal muscle fiber activities
Type 1 muscle fibers contract more __ than type 2a and 2b muscle fibers
slowly
what type of muscle forms the majority of the walls in the digestive system
smooth
match the components of a muscle fiber with its description sarcoplasmic reticulum
smooth endoplasmic reticulum in a muscle fiber
the muscle that surrounds the openings to your esophagus and opens reflexively to allow you to swallow food is what tipe of muscle
sphincter
match the name of the muscle cell component with its function sacroplasmic reticulum
stores calcium ions needed for muscle contraction
true or false: skeletal muscle is usually attached to the skeleton, but it is also found at the openings between the digestive tract and the external environment and the urinary tract and the opening to the external environment
true
ion that is released by the sarcoplasmic reticulum when stimulated
calcium
which of the following proteins are found within a sarcomere
connectin/ actin
Acetylcholine moves across the synaptic cleft by
diffusion
a sarcomere is defined as the distance from one z __ to the next
disc
connective tissue that bundles a myofiber
endomysium
muscle cells are said to have what characteristic because they can respond to stimulation from the nervous system
excitability
intermediate fibers contract __ than slow fibers and __ than fast fibers
faster/slower
in a muscle contraction, as increasing numbers of motor units are recruited __ force is exerted
greater
match each function of skeletal muscle with its description temperature regulation
heat is produced as a waste product of energy usage
match the components of a muscle fiber with its description muscle fiber
a muscle cell
when a muscle fiber contracts, which parts of the sarcomere maintain a constant length throughout contraction
a-band
