Muscle Physiology Flashcards
What is a muscle?
- Largest soft tissue of musculoskeletal system
- Unit of flesh used for movement and weight support
What is it made up of?
actin and myosin
Actin
Actin is a multi-functional proteins that form microfilaments in the cytoskeleton, and the thin filaments in muscle fibrils. It is found in essentially all eukaryotic cells.
(Muscle Contraction)
Myosin
A fibrous protein that forms (together with actin) the contractile filaments of muscle cells and is also involved in motion in other types of cells.
What is its function?
Mobility
Stability
Posture
Circulation
Respiration
Digestion
Urination
Childbirth
Brain Function
Four main properties
Excitability - ability to respond to stimuli;
Contractibility - ability to contract;
Extensibility - ability of a muscle to be stretched without tearing;
Elasticity - ability to return to its normal shape.
types of Muscle
Skeletal
Cardiac
Smooth/ Visceral
what is cardiac muscle?
an involuntary striated muscle tissue found only in the heart and is responsible for the ability of the heart to pump blood.
what is skeletal muscle?
voluntary muscles that connect to your bones and allow you to perform a wide range of movements and functions.
what is smooth muscle?
an involuntary, non-striated muscle inside the walls of hollow organs.
what are the 4 structural patterns of muscles?
-Circular
-Parallel
-Convergent
-Pennate
what are circular muscles?
also called sphincter, fascicles are arranged in concentric rings. They surround external body openings that contract to close.
-eyes and mouth.
what are parallel muscles?
the length of the fascicles run to the long axis of the muscle.
-strap
-fusiform
-fan-shaped
what are convergent muscles?
has a broad origin, and its fascicles converge toward a single tendon of insertion.
-anterior thorax (fan-shaped)
what is pennate muscle?
Standard muscle shape
