The Muscular System & Tissue Flashcards
muscles are distinguished by their ability to transform ___ ___ into directed mechanical energy
chemical energy
(ATP)
what four characteristics enable muscle tissue to perform its duties?
- excitability
- extensibility
- elasticity
- contractility
___ ___ ___ prevent bulging muscles from bursting during exceptionally strong contractions
connective tissue sheaths
___ is the dense connective tissue that surrounds the ENTIRE muscle tissue
epimysium
(eh·puh·mee·see·uhm)
___ is the dense irregular connective tissue that groups muscle fibers into BUNDLES or FASCICLES
perimysium
(peh·ree·mai·see·uhm)
___ is the areolar connective tissue that surrounds INDIVIDUAL muscle fibers
endomysium
enveloped by the perimysium
fascicle
endomysium, epimysium, perimysium & fascicles are all ___ ___ ___
connective tissue sheaths
when muscle fibers ___, they pull
on connective tissue sheaths
contract
the position of a muscle’s ___ & ___ determines the force, velocity, and directionality of skeletal movement
origin & insertion
DIRECT muscle attachments are when a muscle inserts directly into a ___ or ___
bone or cartilage
INDIRECT muscle attachments are when a muscle is connected to a bone through a ___ ___ ___ (much more common)
tendon or aponeurosis
an ___ is a thin sheath of connective tissue that helps connect your muscles to your bones
(is similar to a tendon, but they have different roles)
aponeurosis
(ap-uh-noo-roh-sis)
a ___ ___ contains three specialized structures:
myofibrils
sarcoplasmic reticulum
T tubules
muscle cell
___ ___ are the way that the nervous system connects with skeletal muscles and “tells” them to contract
motor neurons
there are two main categories of contractions:
___ & ___
isotonic & isometric
contraction where the muscle’s length changes while the tension remains constant
isotonic
contraction that occurs when a muscle generates force without changing its length
isometric
ATP stored in muscles is used
ATP is formed from creatine phosphate and ADP
glycogen is broken down to glucose
which is oxidized to generate ATP
ATP is generated by aerobic pathway
the ___ ___ is a metabolic process that uses oxygen to produce ATP
aerobic pathway
___ is a molecule that stores and provides energy for cells
ATP
(adenosine triphosphate)
___ ___ is the post-mortem stiffening of muscles caused by the depletion of ATP from the muscles
Rigor mortis
a type of muscle fiber that contracts slowly and is resistant to fatigue
best suited for endurance type activities like running a marathon
slow oxidative fibers
a type of muscle fiber that contracts fast and is moderately fatigue-resistant
best suited for sprinting or walking
fast oxidative fibers
a type of muscle fiber that contracts fast and is fatigable
best suited for short-term intense movements like hitting a baseball
fast glycolytic fibers
a disorder characterized by widespread musculoskeletal pain accompanied by fatigue, sleep, memory and mood issues
fibromyalgia
ATP for muscle contraction is produced ___ or ___
aerobically or anaerobically
the function of the ___ ___ in muscle contraction is to transmit the action potential deep into the muscle cells
T tubules
the process of adding multiple stimuli that occur in quick succession at a single synapse
temporal summation
the combined effect of a number of motor units acting within a muscle at any given time
multiple motor unit summation
a muscle that has the major responsibility for producing a specific movement is a ___ ___ (or agonist) of that movement
prime mover
muscles that oppose, or reverse, a particular movement are ___
antagonists
___ help prime movers by adding a little extra force to the same movement or by reducing unnecessary movements
synergists
___ are muscles that stabilize a joint or body segment during movement
fixators
the names of some muscles reveal the direction in which their ___ run:
* rectus indicates that the muscle fibers run parallel
* transversus indicates that the muscle fibers run at right angles
* oblique indicates that the muscle fibers run obliquely
fibers
all skeletal muscles consist of fascicles, but the arrangements vary;
the fascicular pattern is CIRCULAR when the fascicles are arranged in ___ ___
concentric rings
(example: orbicularis muscles surrounding the eyes and the mouth)
all skeletal muscles consist of fascicles, but the arrangements vary;
the fascicular pattern is CONVERGENT when its fascicles ___ toward a single tendon of insertion
converge
(example: the pectoralis major muscle of the
anterior thorax)
all skeletal muscles consist of fascicles, but the arrangements vary;
the fascicular pattern is PARALLEL when the length of the fascicles runs ___ to the long axis of the muscle
parallel
(example: the sartorius muscle or the biceps brachii muscle)
all skeletal muscles consist of fascicles, but the arrangements vary;
the fascicular pattern is PENNATE when the fascicles are ___ and they attach obliquely to a central tendon that runs the length of the muscle
short
(three types are unipennate, bipennate, and multipennate)
a ___ allows a given effort either to move a heavier load or to move a load farther/faster
lever
levers in the human body are formed by muscles and bones, and the primary purpose is to produce a ___ ___
three types are first-class, second-class, & third-class
mechanical advantage
the effort & load is at one end of the lever with the fulcrum between
first-class leverage
the lever & fulcrum is at one end of the lever with the load between
second-class leverage
the effort is applied between the load and the fulcrum
third-class leverage
temporalis muscle
masseter muscle
(ma·suh·tr)
orbicularis muscle
platysma muscle
sternohyoid muscle
sternocleidomastoid muscle
gastrocnemius muscle
(ga·straak·nee·mee·uhs)
soleus muscle
muscles used in facial expressions
smile
zygomaticus major
muscles used in facial expressions
pucker
orbicularis muscle
muscles used in facial expressions
pout
mentalis muscle
muscles used in facial expressions
tense neck
platysma muscle
muscles used in facial expressions
angry eyebrows
corrugator muscle
muscles used in facial expressions
blink
orbicularis oculi muscle
muscles used in facial expressions
raised eyebrows
frontal belly of epicranius
in the body,
bones are the levers,
joints are the fulcrums,
and skeletal muscles exert the effort at their ___
insertions
the tendons in the ___ ___ are:
- Extensor pollicis longus
- Extensor pollicis brevis
- Abductor pollicis longus
anatomical snuffbox
the ___ that are responsible for muscle contraction are:
- Actin
- Myosin
- Tropomyosin
- Titin
- Acetylcholine
proteins
also known as the “boxer’s muscle” because it’s used when punching
serratus anterior muscle
helps stabilize the clavicle
subclavius muscle
helps with many arm, neck, and shoulder movements
levator scapulae muscle
part of the rotator cuff
supraspinatus muscle
part of the rotator cuff
infraspinatus muscle
rotates the arm away from the midline
teres minor muscle
rotates the arm towards the midline
teres major muscle
located deep to the trapezius muscle
rhomboid minor muscle
located deep to the trapezius muscle
rhomboid major muscle
primary function is upper extremity movement
latissimus dorsi muscle
