Muscles 1 Flashcards
Within a specific group of muscles, the muscle that is mostly responsible for the action produced is the
prime mover.
The most important factor in decreasing the intracellular concentration of calcium ion after contraction is:
active transport of calcium into the sarcoplasmic reticulum.
active transport of calcium into the synaptic cleft.
ative transport of calcium across the sarcolemma.
active transport of calcium into the sarcoplasmic reticulum.
Holding your head upright is an example of \_\_\_\_\_\_\_\_\_\_ contraction. isotonic isometric eccentric treppe concentric
isometric
Identify the insertion for the Sternocleidomastoid muscle.
Temporal bone
The number of muscle fibers controlled by a single motor neuron:
is greater in muscles where precise control is needed.
is less in postural muscles.
is less in muscles where precise control is needed.
is greater in muscles moving the fingers.
is less in muscles where precise control is needed.
Whenever a muscle fiber is stimulated by a threshold stimulus, it
contracts completely.
Which type of muscle has striations, a single nucleus, intercalated discs, sarcomeres, transverse tubules and gap junctions between the fibers?
Cardiac muscle
You would find dense bodies on which of the following?
Mulit-unit smooth muscle fiber
Identify the origin for the orbicularis oris
Mandible Maxillae
The muscle that adducts and elevates the scapula, and also extends the head is the
trapezius.
The doctor believes that Joe may have skeletal muscle damage. He does a urine test and confirms this diagnosis. What did he find in the urine?
Creatine phosphate
Skeletal muscle fibers are formed from embryonic cells called
myoblasts
Skeletal muscle fibers are multinucleated because
all fibers formed from fusion of many smaller cells during embryonic development.
Energy for muscle contraction comes directly from high-energy bonds of
ATP.
During prolonged muscle contraction, after the initial store of ATP are used up, what energy source will the muscle cell use next?
Creatine phosphate
The protein that helps reinforce the sarcolemma and transmit tension generated by the sarcomeres to the tendons is
dystrophin
Skeletal muscles are attached to muscles, skin or bands of connective tissue (not bone) by
aponeuroses.
Thin filaments at either end of the sarcomere are attached to the
Z line.
After death, muscle fibers run out of ATP and calcium begins to leak from the sarcoplasmic reticulum into the sarcoplasm. This results in a condition known as
rigor mortis.
What is the origin (bone) for the teres minor muscle?
scapula
The smallest stimulus capable of causing a contraction is a/an
threshold stimulus.
Active sites on the actin become available for binding when calcium binds to tropomyosin. myosin binds to troponin. troponin binds to tropomyosin. actin binds to troponin. calcium binds to troponin.
calcium binds to troponin.
The sliding filament mechanism of muscle contraction involves
myosin filaments sliding along collagen fibers.
collagen fibers sliding along actin filaments
elastin fibers sliding along myosin filaments.
actin filaments sliding along myosin filaments.
actin filaments sliding along myosin filaments.
When energy reserves in a muscle are exhausted and lactic acid levels increase, \_\_\_\_\_\_ occurs: fatigue atrophy treppe tetanus
fatigue
A disorder caused by a bacterial neurotoxin that prevents release of acetylcholine from synaptic end bulbs, possibly causing paralysis of breathing muscles, is known as
botulism.
The muscle that plantar flexes the foot and flexes the leg is the
gastrocnemius
The movable attachment of a muscle is the
insertion.
