Anaphy Flashcards
There are more than ______ skeletal muscles in the body.
From what % of our body weight is skeletal muscle.
40% - 50%
Delicate connective tissue membrane that covers specialized skeletal muscle fibers.
Endomysium
Tough connective tissue binding together fascicles.
Perimysium
Coarse sheath covering the muscle as a whole.
Epimysium
These three fibrous components may become a tendon or aponeurosis.
Endomysium, Perimysium, Epimysium
range from extremely small to large masses.
Size
variety of shapes, such as broad, narrow, long, tapering, short, blunt, triangular, quadrilateral, irregular, flat sheets, or bulky masses.
Shape
parallel to long axis, converge to narrow attachment, oblique, pennate, bipennate, or curved.
Arrangement
point of attachment that does NOT move when muscle contracts.
ORIGIN
point of attachment that moves when the muscle contracts.
INSERTION
Muscles that contract at the same time as the prime movers and they facilitate movers action to produce a more efficient movement.
SYNERGISTS
A muscle or group of muscles that directly performs a specific movement.
PRIME MOVER
Most movements are produced by the coordinated action of several muscles, some muscles in the group contract while others relax.
MUSCLE ACTION
Muscles that, when contracting, directly oppose prime movers.
ANTAGONIST
joint stabilizes.
Fixator muscles-
Provide precision and control during contraction of prime movers.
ANTAGONIST
Fulcrum lies between the pull and the load. Not abundant in the human body.
FIRST CLASS LEVER
Load lies between the fulcrum and the joint at which the pull is exerted.
SECOND CLASS LEVER
Pull is exerted between the fulcrum and load.
THIRD CLASS LEVER
Unique in that at least one point of attachment is to deep layers of the skin over the face or neck.
Muscle of facial expression
Permit rapid and extensive movement.
Most common
THIRD CLASS LEVER
Responsible for chewing movement.
Muscles of mastication
Paired muscles on either side of the neck are responsible for head movements.
Muscles that move the head
Critical importance in respiration.
Muscles of the thorax
Arranged in three layers with fibers in each layer running in different directions to increase strength.
Muscles of the abdominal wall
Bend to stabilized the back.
Muscles of the back
Support the structures in the pelvic cavity.
Muscles of the pelvic floor
Muscles that attach the upper extremity to the torso are located anteriorly or posteriorly.
Muscles acting on the shoulder girdle
The shoulder is a synovial joint allowing extensive movement in every plane motion.
Muscles that move the upper arm
Found proximally to the elbow and attach to the ulna and radius.
Muscles that move the forearm
These muscles are located on the anterior or posterior surfaces of the forearm.
Muscles that move the wrist, hand, and fingers.
The pelvic girdle and lower extremity function in locomotion and maintenance of stability.
LOWER LIMB MUSCLES
Muscles that move the thigh and lower leg.
LOWER LIMB MUSCLES
Muscles that move the ankle or foot.
LOWER LIMB MUSCLES
Located in the leg and exert their actions by pulling on tendons that insert on bones in the ankle and foot.
Extrinsic foot muscles
Responsible for dorsiflexion, plantar flexion, inversion, and eversion.
Extrinsic foot muscles
Located within the foot and responsible for flexion, extension, abduction, and adduction of toes.
Intrinsic foot muscles
body alignment that most favors functions and requires the least muscular work to maintain and keeping the body’s center of gravity over its base.
GOOD POSTURE
Movement of the body as a whole or of its part.
Heat production.
Posture
MUSCULAR PHYSIOLOGY
ability to stimulate.
Excitability
ability to contract, or shorten, and produce body movement.
Contractility
ability to extend, or stretch, allowing muscles to return to their resting length.
Extensibility
Muscle cells are called _____ because of their threadlike shape.
FIBERS
plasma membrane of muscle fibers.
Sarcolemma
Network of tubules and sacs found within muscle fibers.
Sarcoplasmic Reticulum
This continually pumps CALCIUM IONS from the sarcoplasm and stores the ions within its sac.
Sarcoplasmic Reticulum
numerous fine fibers packed close together in sarcoplasm.
MYOFIBRILS
A segment of myofibril between 2 successive Z lines.
SARCOMERE
Dark stripes called
A BANDS
zone runs across midsection of each dark A bands.
Light H
Light Stripes called
I bands.
line extends across center of each light I band.
Dark Z
Transverse tubules extend across the sarcoplasm at right angles to the long axis of the muscle fibers.
T TUBULES
Formed inward extensions of the sarcolemma.
T TUBULES
Membrane has ion pumps that continually transport Calcium Ions inward from the sarcoplasm.
T TUBULES
Allow electrical impulses travelling along the sarcolemma to move deeper into the cells.
T TUBULES
\Each myofibril contains thousands of thick and thin myofilament
~~~
MYOFILAmENTS
Makes up almost all the thick filament.
Myosin
“Heads” are chemically attracted to actin molecules.
Myosin
“heads” are known as cross bridges when attached to actin.
Myosin
Globular protein that forms two fibrous strands twisted around each other to form the bulk of the thin filament.
ACTIN
Protein that blocks the active sites on the actin molecules.
TROPOMYOSIN
Protein that holds tropomyosin molecules in place.
TROPONIN
A skeletal muscle fiber remains at rest until stimulated by a motor neuron.
Excitation and Contraction
motor neurons connect to the sarcolemma at the motor end plate.
Neuromuscular Junction
The neurotransmitter released into the synaptic cleft that diffuses across the gap, stimulates receptors and initiates an impulse in the sarcolemma.
Acetylcholine
that a muscle can develop bears a direct relationship to the initial length of its fiber.
Maximal strength
are compressed, therefore the muscle cannot develop much tension.
A shortened muscle’s sarcomeres
Contraction in which the one or tension within a muscle remains the same as the length of the muscle changes.
Isotonic Contraction
muscle shortens as it contracts.
Concentric
muscle lengthens while contracting.
Eccentric
Contraction in which muscle length remains the same while the muscle tension increases.
Isometric contraction
