Muscle physiology Flashcards
Name three types of muscle tissue
cardiac, smooth, skeletal
-controlled involuntary, and found only in the heart
-One nucleus
- Found in the wall of the heart
-pumps blood through the body
-striated
cardiac
-long cylindrical striated cells with many nuclei
-voluntary contraction
-most are found attached to the bones
-Responsible for voluntary movement
- striated
-multiple nuclei
skeletal
-Involuntary contraction
- found in walls of hollow internal organs, such as the intestine, and tubes, such as blood vessels
-unstriated
smooth
found in the cardiac muscle, and with the gap junction connect the cells and enable increased electroconductivity in the heart allowing cells to beat together as one unit.
intercalculated disc
actin filaments, type of sarcomere
composed of actin protein but also troponin and tropomyosin
thin
myosin filament. type of sarcomere
composed of myosin protein
Have myosin head or myosin cross-bridge
thick
made up of actin and myosin,
- make up myofibrils
sarcomere
one motor neuron and all the muscle cell it innervates
motor unit
is a process of increasing the number of motor units that are active in a muscle at any given time
recruitment
Describe the role of that Ca2+ plays in muscle contraction
Ca2+ stimulates the movement of tropomyosin allowing the cross bridge to bind to actin and perform a power stroke
When the relaxation and recovery periods are not allowed to occur due to an increase frequency of stimuli, BLANK occurs in the whole muscle
summation
Summation is followed by BLANK, when all calcium is bound and no greater strength in contraction can be achieved.
tetanus
muscle cells/fibers contain specialized organelles called
myofibrils
cover up the myosin binding sites on the actin filament, preventing cross-bridge formation and thus inhibiting the sarcomere from contracting
tropomyosin
