Lecture 5 - Skel Musc. Contraction Flashcards
The plasma membrane of the muscle fiber is called the? 2 names
Sarcolemma or plasmolemma
Calcium is stored in ?
SR
The contractile unit is called the?
Sarcomere
The large to small organization of a muscle? 5 parts
Muscle - Fasciculus - MyoFiber - MyoFibril - MicroFilament
What holds the Sarcomere together that runs down the middle of the Sarcomere Z line to Z line and through the myosin?
Titan
Fluid that surrounds the MyoFibrils?
Sarcoplasm
which bands/lines change length and which stay the same?
Z A stay same or ZAme
H I change.
which chains of the myosin control the function of the myosin head? light or heavy
Light
What unique function does myosin have that allows it to complete this contraction process.? think enzyme
IT can function as an ATPase enzyme and cleave ATP for E?
Ca is release from the _________ and binds to ________ ?
SR
Troponin complex on F - Actin
define summation and tetany
Summation is where the # contractions are additive to increase overall muscle contraction
Tetany occurs when The frequency of contraction is so high that there is only contraction and no relaxtion. Also no additional increase in frequency has any effect. Ca ions are maintained in the muscle Sarcoplasm.
- what does multiple fiber summation come from?
- frequency summation?
which one leads to tetany?
- an INCREASE IN # OF motor units firing.
2. an increase in Frequency of Contractions and leads to tetanization.
Which part of the muscle can increase in number ?
The the Myofibril.
define isometric?
define isotonic and its 2 types?
isometric, Change in tension with NO change in length
isotonic, Constant tension with change in length.
concentric, shortening
eccentric, lengthing
for a muscle contraction, Work =
W = Load x Distance
