muscles Flashcards
endomysium
muscle fiber surrounded by collagen
fascicle
Bundles of muscle fiber wrapped by perimysium
muslce
bundle of fascicles
epimysium
covers and entire muscle
what is the tendon continuous with on the bone?
periosteum
myofibrils
bundles of thin actin and thick myosin filaments arranged in an orderly fashion
sarcomere
repeating units of contraction that make up the myofibrils
When building muscle is it more likely to build the current muscle cells or synthesize new cells?
90% of the time the current muscle cells get bigger. 10% of the time new muscle cells are synthesized.
Whats the name of the cell that synthesizes new muscle?
Satellite cells
sarcolemma
refers to the outer plasma membrane of the cell and it is excitatory because an action potential can run thru the sarcolemma.
sarcoplasmic reticulum
it is an endoplasmic reticulum that is a closed compartment surrounding every myofibril.
what is the purpose of the sarcoplasmic reticulum?
calcium pumps in the sarcoplasmic reticulum cause it to take up calcium ions from the sarcoplasm.
muscle tone
degree of contraction of a muscle. readiness to fire a contraction
what happens it deep rem sleep?
your muscle tone starts to shut down
circular muscle
orbicularis oculi and orbicularis oris (mouth)
convergent muscle
pectoralis major
parallel muscle
sartorius (lateral quad) and biceps brachii
bipennate
rectus femoris (quad)
unipennate muscle
extensor digitorum longus (near the tibia)
characteristics of pennate muscles
tend to be composed of red fibers
type I muscles (red twitch)
Oxidative (aerobic) High endurance High myoglobin Postural (anti-gravity) Low force
type II muscles (white twitch)
Glycolytic (anaerobic)
Low endurance
Low myoglobin
High force
muscle role: stabilizing
Type I fibers Deep Single joint Postural ie Brachialis, Soleus
muscle role: mobilizing
Type II fibers
Superficial
2-joints
ie Biceps brachialis
Gastrocnemiusorigin
Fixed attachment
instertion
Mobile attachment
nerve supply
Innervation
action
Movement of affected joint(s)
agonist
Prime mover
antagonist
opposes the agonist. ex.) Tricep is the antagonist to the bicep.
synergist
helps the agonist. ex.) The brachialis is the synergist to the bicep when doing curls
stabilizer
muscles for posture, they allow for the smoothness of movements by supporting the joints during movements
skeletal muscle
responsible for voluntary movements.cells appear striped because of the regular arrangement of sarcomeres. MULTINUCLEATED
smooth muscle
usually long and spindle-shaped, and each cell has a single nucleus. the actin and myosin filaments are not as regularly arranged as they are in the skeletal and cardiac muscle.
what do smooth muscles do and what controls them?
Controlled by the autonomic nervous system. Smooth muscle provide contractile force for most organs, moves food thru digestive system, empties bladder and controls flow of blood thru blood vessels.
cardiac muscle
appears striated as does skeletal muscle because of the regular arrangement of actin and myosin filaments into sarcomeres. but they are much smaller and have only ONE nucleus.
how are cardiac muscles arranged?
the cells interdigitate to form a meshwork that is resistant to tearing. cardiac muscles need to be strong to handle high pressures that occur while pumping blood.
neuromuscular junction
connects the nervous system to the muscular system via synapses between efferent nerve fibers and muscle fibers, also known as muscle cells
