Cardiac Muscle Flashcards
State the functional aspects of cardiac muscle
Longer contractions compared to skeletal mm
Longer refractory periods which prevent tetanic contractions
Cannot undergo wave summation, prolonged contractions by accumulating many together
Cannot undergo tetanic contractions, quick contractions that don’t relax, a heart in this state cannot pump blood.
Describe the structure of cardiac muscle
Shorter, flatter and branched.
Connected at intercalated discs which contain
Desmosomes, these prevent separation of cardiac muscle during contraction.
Gap junctions, these allow the spread of depolarisation to travel to sequenced areas of the heart, allowing it to function as one single functional unit or syncintium.
T tubules are short
No terminal cisternae, therefore no triads
They protrude at the z disks not zone of overlap
Calcium released from the SR
Single central nucleus
Mitochondria, highly dependent on aerobic respiration
