Muscle Tissue Flashcards
Smooth Muscle (comparison)
spindle-shaped, nonstriated uninucleated fibers
occurs in walls of internal organs
INVOLUNTARY
What is Muscle Tissue?
primary tissue type divided into:
skeletal muscle
cardiac muscle
smooth muscle
Cardiac Muscle (comparison)
striated, branched, uninucleated fibers
occurs in wall of HEART
INVOLUNTARY
Skeletal Muscle (comparison)
striated, tubular, multinucleated fibers
usually attached to skeleton
VOLUNTARY
Skeletal Muscles (intro)
attached to skeletal system
allow us to move
FUNCTIONS of Skeletal Muscles
- produce movement of the skeleton
- maintain posture & body positioning
- supports soft tissue
- guard entrances & exits
- maintains body temp
Skeletal Muscle STRUCTURES
- muscle tissues (muscle cells or FIBERS)
- connective tissue: consists of 3 layers
epimysium, perimysium, endomysium
Epimysium
(layer in connective tissue)
sorrounds entirem muscle, and separated from sorrounding tissue
Perimysium
(layer in connective tissue)
divides muscle into fascicles
Endomysium
(layer in connective tissue)
sorround muscle fascicles
ORGANIZATION of Skeletal Muscle
the end of the 3 layers emerge to form:
tendon or aponeurosis
Nerves
skeletal muscles are VOLUNTARY muscles,
controlled by nerves of the Central Nervous System
( brain & spinal cord )
Blood Vessels
supply large amounts of OXYGEN & NUTRIENTS
carries away wastes
Muscle Fiber Stimulation ( Wave Summation)
repeated simulation before the relaxation phase
ex. bicep curl
Muscle Fiber Stimulation ( Incomplete Tetanus )
if rapid stimualtion continues and muscle is not allowed to relax, twitches reach maximum level of tension.
ex. incomplete curl
Muscle Fiber Stimulation ( Complete Tetanus )
if stimulation frequency is high enough, muscle fiber begins to relax, and is in continuous contraction
ex. completed curl
ATP Generation ( Aerobic Metabolism )
- primary energy source of resting muscles
- breaks down fatty acids
- ATP (Adenosine Tri Phosphate) transports chemical energy within cells
ATP Generation ( Anaerobic Glycosis)
- primary energy source for peak muscular activity
- produces 2 ATP molecules per molecule of glucose
- breaks down glucose from glycogen stored in skeletal muscles
Energy Use & Level of Muscle Activity
- skeletal muscles at rest metabolize fatty acids and store glycogen
- during moderate activity, muscles generate ATP through anaerobic breakdown of carbohydrates, lipids, or amino acids
- at peak activity, energy is provided by anerobic reactions that generate lactic acid as a by-product
Muscle Fatigue
- when muscles can no longer perfrom a required activity
Results of Muscle Fatigue
- depletion of metabolic reserve
- damage to muscle components
- low pH ( lactic acid)
- muscle exhaustion & pain
Physical Conditioning ( Muscle Hypertrophy)
muscle growth from heavy training
- increases diameter of muscle fibers
- increases number of myofibrils
Physical Conditioning ( Muscle Atrophy )
lack of muscle activity
- reduces muscle size, tone, and power
Muscle Origin
beginning part of any muscle ( always stationary )
muscles are named according to its origin, insertion, or according to their actions.
Muscles Insertion
the ending part of any muscle ( always moves )
musclesn are named according to its origin, insertion, or according to their actions.
Muscle Actions ( Primary Action Categories)
prime mover ( agonist ), synergist, antagonist
Muscle Action ( Primary Mover)
( agonist )
main muscle in action
Muscle Action ( Synergist )
helper muscle in action
Muscle Action ( Antagonist )
opposed muscle to an action
Divisions of Muscular System
Axian & Appendicular Muscles
Axial Muscles
- position head and spinal cord ( muscles of head, neck, & spine ) - muscles of the trunk ( oblique & rectus muscles ) - move rib cage ( muscles of pelvic floor ) - 60% of skeletal muscles
Appendicular Muscles
- support pectoral and pelvic girdles ( positions & stabalizes ) - support limbs ( movement ) - 40% of skeletal muscles
Muscles of Pelvic Floor ( Functions )
- support organs of pelvic cavity
- flex sacrum & coccyx
- control movement of materials through urethra & anus.
Effects of Aging on the Muscular System
- skeletal muscle fibers become smaller in diameter
- skeletal muscles become less elastic
( develop increasing amounts of fibrous tissue ) FIBROSIS - decreased tolerance for exercise
- drcreased ability to recover from muscular injuries
Cardiovascular System
delivers oxygen and fuel
removed carbon dioxide and wastes
Respiratory System
responds to oxygen demand of muscles
Integumentar System
disperses hest from muscle activity
Nervous & Endocrine System
direct responses of all systems
