Skeletal Muscle Flashcards
(48 cards)
Black arrows?
Type I fibers
What is alpha actinin
protein that attaches thin filaments to the Z-line
Blue arrows?
Type II fibers
Arrows?
Myocyte nuclei
What is alpha-beta crystallin?
a heat shock protein that protects desmin from mechanical stress.
What is nebulin?
A molecule that lies on top of actin filaments in the sarcomere. It regulates the length of an actin filament.
Identify
Cardiac muscle, Acute MI
What are satellite cells?
Cells that attach to myotubes before the basal lamina is laid down. They function as stem cells and give rise to myogenic precursor cells (replaces damaged muscle).
What is the dystroglycan complex?
It links dystrophin (intracellular) to laminin-2 (extracellular).
smooth muscle
Smooth muscle
What is type I myofiber also known as?
red/dark fibers
skeletal muscle
What are the 3 types of muscle tissue?
smooth, skeletal and cardiac
Smooth muscle
What is speed of contraction of type I myofibers?
slow and continuous
What is one way that smooth muscle and skeletal muscle differ?
Smooth muscle has single mononucleated cells and skeletal muscle has many cells.
Why are type IIB myofibers light?
They have little to no myoglobin; type IIA uses ANAEROBIC respiration.
Blue arrows?
Type II fibers
Identify
Muscle spindle
Why is type I myofiber dark?
due to the large armount of hemoglobin in the fibers; type I myofibers use OXIDATIVE PHOSPHORLYATION. They also have high ATP, and NADH
What are the components of a neuromusclar spindle?
extrafusal fibers, intrafusal fibers, alpha motor neurons, gamma motor fibers, primary and secondary afferent fibers.
If NAD stain is dark in myofibers, what does that indicate?
The myofiber is high NAD, and hence uses oxidative phosphorylation. It is probably at type 1 myofiber.
what are two features of cardiac muscle visible in a picture?
intercalated discs and sarcomeric arrangement.
