AP02 - muscle tissue Flashcards
Which molecules would you find in the sarcomere?
myosin, actin, tropomyosin, and troponin
What is the difference between type I and type II fibres?
type I are slow twitch, requiring a greater blood supply
Type II respire anaerobically
What junctions would you find in cardiac muscle connections?
Gap junctions
Desmosomes
What do intercalated discs contain?
desmososmes and fascia adherens
How many actin filaments surround each myosin filament?
6-11
What are t-tubules?
invaginations of the sarcolemma
What happens in MD?
Muscular Dystrophy
mutations of the dystrophin gene lead to defective linkages of cytockeletal fibres, causing atrophy of muscle fibres
Where would you find branching?
cardiac muscle
Where are the nuclei in differet muscle types?
in smooth and hence cardiac muscle, they’re in the middle, but in skeletal muscle cells they are oval in shape and peripheral.
How does smooth and skeletal muscle differ in shape?
smooth muscle is fusiform, where skeletal is usually cylindrical
How would you explain the difference in innervation between type I and type II fibres?
the gain function models of type I show the feuency of oscillation is a continuous function, were type II muscles show discontinuity
This allows type II fibres to fire in much quicker succession
What other structure would you find in cardiac muscles?
lipid droplets to act as respiratory substrates
What do spindle fibres detect?
changes in muscle tone, they contract to combat the lengthening of muscle tissues
