muscle tissue Flashcards
What are the 3 types of muscle tissue?
Skeletal, cardiac, smooth
Contractile tissues
muscle tissues are contractile tissues, they generate tension and movement
Skeletal muscle tissue
Most are attached to the bones of the skeleton by tendons, called muscle fibers, perform voluntary movements, multinucleate, and they are striated
Multinucleate
Each cell has more than one nucleus
Striations
Alternating light and dark bands that can be seen when muscle tissue is examined with a microscope
What are some functions of the skeletal muscle tissue?
Producing voluntary body movements, maintaining posture, breathing movements, and generating heat
Cardiac muscle tissue
Found only in the walls of the heart, responsible for the heartbeat, uninucleate, striated, action is involuntary, has intercalated discs
Uninucleate
One nucleus per muscle fiber
Involuntary actions
Contraction and relaxation is not consciously controlled
Autohythmicity
The built-in rhythm of the heart created by the pacemaker
Intercalated discs
Interlocking attachment sites between cardiac muscle fibers
Desmosomes
Cell junctions that firmly hold cardiac muscle cells together
Gap junction
Protein channels for electrochemical signals to pass from cell to cell stimulate the heartbeat
Smooth muscle tissue
Located on the walls of hollow internal structures, non-striated, spindle-shaped muscle fibers with one nucleus, involuntary control, move substances within the body, contraction of this muscle tissue can cause constriction and dilation
Peristalsis
the smooth muscle moves food through the gastrointestinal tract and produces a wave-like motion
Contraction of smooth muscles
causes constriction of blood vessels, which reduces blood flow and increases blood pressure
Relaxation of smooth muscle
walls dilate blood vessels, which increases blood flow and lowers blood pressure
Excitability
Ability to respond to nervous stimulation or electrical stimulation
Contractility
Ability to contract forcefully when stimulated. If enough tension is generated, the muscle tissue shortens and movement occurs
Extensibility
Ability to stretch without tearing
Elasticity
Ability to return to the muscle tissues’ original length after stretching or after contracting
What tissue types do skeletal muscles contain?
They contain all 4 primary tissue types.
Tendon
is a cord of dense regular connective tissue that attaches a muscle to the periosteum of the bone
Aponeurosis
is a broad, flattened tendon
Areolar connective tissue
Surrounds and protects individual muscle fibers
Dense irregular connective tissue
Surrounds bundles of muscle fibers called fascicles
Fascicle
A bundle of 10-100 muscle fibers within a muscle. Are held together by dense irregular connective tissue. Give muscle its “grain”
Deep fascia
Refers to the sheet of dense irregular connective tissue that surrounds groups of muscles and separates the muscles into functional compartments