Muscular System Flashcards
3 Types of Muscle:
Skeletal Muscle, Cardiac Muscle, Smooth Muscle
Muscle Cells that are elongated.
Muscle Fibers
The ability of a muscle to shorten forcefully, or contract.
Contractility
The capacity of muscle to respond to a stimulus.
Excitability
A muscle can be stretched beyond its normal resting length and still be able to contract.
Extensibility
The ability of a muscle to recoil to its original resting length after it has been stretched.
Elasticity
Large, cigar-shaped, multinucleate cells with obvious striations; largest muscle fibers.
Skeletal Muscle
Speed of contraction of a Skeletal Muscle.
Slow to fast
Found only in heart where it forms the bulk of the heart walls.
Cardiac muscle
Speed of contraction of a cardiac muscle.
Slow
Found mostly in the walls of hollow visceral organs.
Smooth Muscle
Speed of Contraction of a Smooth Muscle.
Very Slow
What are the connective tissue coverings?
- Tendons
- Epimysium
- Perimysium
- Endomysium
It is the muscular fascia.
Epimysium
It covers the fasicle.
Perimysium
It covers muscle fibers.
Endomysium
Types of Skeletal Muscle Fibers:
Chemical Component Structures, Mechanical Component Structures
Electrical Component Structures are consist of:
Sarcolemma, Trasverse tubules (T tubules), Sarcoplasmic Reticulum
It is the plasma membrane.
Sarcolemma
Carry electrical impulses into the center of the muscle fiber to contract in unison.
Transverse Tubules (T-tubules)
Highly specialized smooth endoplasmic reticulum in skeletal muscle fibers that stores high levels of calcium.
Sarcoplasmic Reticulum
Mechanical Component Structures are consists of:
Myofibrils, Myofilaments
A globular subunits that has an active site fo4 myosin.
G Actin Molecules
Long, fibrous protein covering the active sites on the G actin.
Tropomyosin
It is attached at specific intervarls along the actin myofilaments; a subunit that binds Ca2+.
Troponin
2 myosin heavy chains.
Rod Portion
Nane the 2 Myosin Heads.
Myosin light chains and Hinge Region
The basic structural and functional unit of a skeletal muscle. It is the smallest portion of a skeletal muscle capable of contracting.
Sarcomeres
Gap between nerve endings and sarcolemma.
Synaptic Cleft
Contains a neurotransmitter called a ACETYLOCHOLINE.
Synaptic Vesicles
Chemical that stimulates skeletal muscle fiber.
Neurotransmitter
Electrical current generated by the Na+ -K+ pump.
Action Potential
Boundary of each sarcomere.
Z-Disks
Contains only actin myofilaments (including Z-disks).
I Band
Contains both actin and myosin myofilaments.
A Band
Give the 2 Types of Muscle Contractions:
Isotonic Contraction and Isometric Contraction