Muscular System Flashcards
an organ system consisting of skeletal,
smooth and cardiac muscles
Muscular system
what stores substances in smooth muscles?
Sphincter
movement of food in the gastrointestinal tract (GIT)
Peristalsis
function of the cardiac muscle
pumps blood`
Production of heat as the muscle
contracts
Thermogenesis
Involuntary contraction of cells
shivering
The ability of the muscular tissue to respond to certain stimuli by producing electrical signals called “action
potentials”
ELECTRICAL EXCITABILITY
The ability of muscular tissue to contract
forcefully when stimulated by an action
potential.
CONTRACTILITY
The ability of muscular tissue to stretch,
within limits, without being damaged.
EXTENSIBILITY
The ability of muscular tissue to return to its
original length and shape after contraction
or extension.
ELASTICITY
Are attached to bones by tendons, and they
produce all the movements of body parts in
relation to each other and under voluntary control
SKELETAL MUSCLE
another term for subcutaneous layer in skeletal muscle
hypodermis
components of the subcutaneous layer
Areolar connective tissue
Adipose tissue
Provides entry for nerves and blood vessels
and Insulates muscle and protects from trauma
subcutaneous layer
Dense sheet or broad band of irregular connective tissue Lines the body wall and limbs Supports and surrounds muscles and other organs
fascia
Broad, flat sheet
aponeurosis
Outermost layer of connective tissue
Consist of dense connective tissue
Encircles the entire muscle
epimysium
Dense connective tissue
Separates group of 10-100 muscle fibers into
FASCICLES
perimysium
Inner most layer of connective tissue
Reticular fiber
Encircles individual muscle fiber
endomysium
how many artery, veins and nerve is the skeletal muscle usually composed of?
1 artery, 1 or 2 veins,
and 1 nerve
Neurons that stimulate skeletal muscle
contraction
Somatic motor neurons
do muscular tissue contain capillaries?
yes
Plasma membrane of a muscle cell
SARCOLEMMA
Extensions of the plasma membrane that
penetrate to the center of each muscle fiber
Ensures that action potential excites all parts of
the muscle fiber.
TRANSVERSE TUBULES
The cytoplasm of muscle fiber
sarcoplasm
provides oxygen to muscle fiber
myoglobin
what is needed for ATP synthesis in a muscle fiber?
glycogen
this organelle produces ATP
mitochondria
The contractile organelles of skeletal muscle
Makes the muscle fiber appear striated
myofibrils
Encircles each myofibril
SARCOPLASMIC RETICULUM
Dilated end sacs of sarcoplasmic reticulum
TERMINAL CISTERNS
Basic contractile unit of muscle fiber or basic
functional unit of myofibril
SARCOMERE
what myofilaments are present in sacromere?
actin and myosin
Thin Filaments: Actin
Thick Filaments: _____
Myosin
Separates one sarcomere from the next
z-disc
Darker, middle part of sarcomere
Extends the entire length of thick filament
Has zone of overlap
a band
Lighter, less dense area
Contains only thin filaments
Z-disc passes through its cente
I BAND
Lies in the center of A band
Consist only of thick filaments
H-ZONE
Located at the middle of the sarcomere
Holds the thick filaments at the center
M LINE
Group of inherited muscle-destroying diseases
that cause progressive degeneration of skeletal
muscle fibers
MUSCULAR DYSTROPHY
Region where communication occurs
between neurons and target cell
Synapse
Gap that separates the two cells
Synaptic cleft
The end of a motor neuron
Axon terminal
It is the synapse between a somatic motor
neuron and a skeletal muscle fiber where
muscle action potentials arise
NEUROMUSCULAR JUNCTION
Muscular part of the NEUROMUSCULAR JUNCTION
MOTOR END PLATE
delivers the action potential to terminal cisterns
transcerse tubules
recognizes the action potential and delivers
calcium to the sarcoplasm
TERMINAL CISTERNS
Produced during muscle relaxation where ATP
production exceeds ATP consumption
CREATINE PHOSPHATE
Catalyzes transfer of phosphate group from
ATP to creatine, forming creatine phosphate
and ADP
CREATINE kinase
The entire process by which the breakdown of
glucose gives rise to lactic acid when oxygen is
absent or at low concentrations
ANAEROBIC GLYCOLYSIS
Series of oxygen-requiring reactions (Krebs
cycle and electron transport chain) that
produces ATP, CO2, water, and heat
AEROBIC GLYCOLYSIS
Responsible for muscle soreness
Lactic acid build-up
The inability of a muscle to maintain force of
contraction after prolonged activity
MUSCLE FATIGUE
Feeling of tiredness and desire to cease
the activity
Occurs before muscle fatigue
Caused by changes in the CNS
Central Fatigue
Refers to added oxygen, over and above
the resting oxygen consumption, taken by
the body after exercise
OXYGEN DEBT
A small amount of tautness or tension in the
muscle due to weak, involuntary contractions of
motor units.
muscle tone
