Mascular Flashcards
Types of Muscle Tissue
- Skeletal muscle
- Cardiac muscle
- Smooth muscle
elongated muscle cells eg. Skeletal and smooth muscle cells
Muscle fibers
(prefix) both are word
roots meaning “muscle”
Myo or mys
meaning flesh
Sarco
attach to and cover the bony skeleton.
Skeletal Muscle
the longest muscle cells and have obvious stripes called striations
Skeletal Muscle
A voluntary muscle because it is subject to conscious control.
Skeletal Muscle
responsible for overall body mobility
Skeletal Muscle
tires easily and must rest after short periods of activity.
Skeletal Muscle
occurs only in the heart
Cardiac Muscle
cardiac muscle cells are striated
Cardiac Muscle
involuntary muscle
Cardiac Muscle
contracts at a fairly steady rate set by the heart’s pacemaker
Cardiac Muscle
consists of elongated cells
Smooth Muscle
found in the walls of hollow visceral
organs, such as the stomach, urinary
bladder, and respiratory passages
Smooth Muscle
has no striations
Smooth Muscle
involuntary muscle
Smooth Muscle
capacity of muscle to respond to a stimulus
Excitability
ability of a muscle to shorten and generate pulling force
Contractility
muscle can be stretched back to its original length
Extensibility
ability of muscle to recoil to original resting length after stretched
Elasticity
Muscle Functions
- Body movement (Locomotion)
- Maintenance of posture
- Respiration
– Diaphragm and intercostal contractions - Communication (Verbal and Facial)
- Constriction of organs and vessels
– Peristalsis of intestinal tract
– Vasoconstriction of b.v. and other structures (pupils) - Heart beat
- Production of body heat (Thermogenesis)
stimulate muscle fibers to contract
neuron axons branch so that each muscle fiber (muscle cell) is innervated form a neuromuscular junction (= myoneural junction)
Motor neurons
Dense regular c.t. surrounding entire muscle
–Separates muscle from surrounding tissues and organs
–Connected to the deep fascia
Epimysium
Collagen and elastic fibers surrounding a group of muscle fibers
called a fascicle
–Contains b.v and nerves
Perimysium
Loose connective tissue that surrounds individual muscle fibers
–Also contains b.v., nerves, and satellite cells (embryonic stem cells function in repair of muscle tissue
Endomysium
consists of a hundreds to thousands of cell muscle, plus connective tissue wrappings, blood vessels, and nerve fibers.
-covered externally by the epimysium
muscle(organ)
discrete bundle of muscle cells, segregated from the rest of the muscle by a connective tissue sheath.
-surrounded by perimysium.
fascicle(a portion of the muscle)
is an elongated multinucleate cell; it has banded (striated) appearance.
-surrounded by endomysium.
muscle fiber(cell)
3 layers of Connective Tissue Sheaths
- Epimysium
- Perimysium
- Endomysium
Skeletal muscles span joints and attach to bones (or
other structures) in at least two places called?
insertion and origin
the movable bone when a muscle contracts
insertion
immovable or less movable bone were the
movable bone moves towards
origin
it is a cell membrane that surrounds the sarcoplasm, it contains many of the same organelles seen in other cells, it is also an abundance of the oxygen-binding protein myoglobin, and Punctuated by openings called the transverse tubules (T-tubules)
Sarcolemma
it is the cytoplasm of fiber
sarcoplasm
cylindrical structures within muscle fiber, and are bundles of protein filaments (=myofilaments)
Myofibrils
Two types of myofilaments
- Actin filaments
- Myosin filaments
it is a thin filaments
Actin filaments
it is a thick filaments
Myosin filaments
are rodlike contractile elements that occupy most of the muscle cell volume. composed of sarcomeres arrange end to end, they appear bonded, and bands of adjacent are aligned.
myofibrils
contractile unit, composed of myofilaments made up of contractile proteins.
sacromere
types of myofilaments that contain bundled myosin molecules
thick filaments (myosin filaments)
types of myofilaments that contain actin molecules
thin filaments (actin filaments)
