Muscle questions Flashcards
What is the meaning of the term fiber as it is used in regard to muscle?
Muscle cell
Which component of the nervous system innervates smooth muscle?
Autonomic
What type of muscle has the slowest rate of contraction?
Type I red fibers
-slow twitch
What other tissues are usually found in association with muscle?
Connective tissue
In cross section, only some smooth muscle cells will appear to have nuclei. Why is this the case?
Smooth muscle cells are uninucleated
-due to the elongation of the muscle fiber the cross section my not cut through nucleus
What component of the H&E dye combination stains the sarcoplasm of muscle cells
Eosin
Why is skeletal muscle referred to as voluntary muscle?
Innervated by cerebrospinal nerves and is under control of the individual
After injury what cell is primarily responsible for repair of skeletal muscle
Satellite cells
The connective tissue that establishes bundles of skeletal muscle fibers is known as the
Perimysium
In which type of muscle are the nuclei located at the periphery of the fibers?
Skeletal muscle
The cross banded appearance of both skeletal and cardiac muscle is due to the presence of
myofibrils
In skeletal muscle, the portion of one myofibril btwn 2 adjacent Z lines is called the
sarcomere
In skeletal muscle, the thin dark line within the H bad is the
Thick filament Myosin
The regularity of sarcomere structure is maintained by a large protein called
titin
what happens to the number of satellite cells per muscle fiber as we grow older?
Decrease
Which skeletal muscle type is most resistant to fatigue?
Red fibers Type I
In which type of muscle do the fibers branch and anastomose?
Cardiac muscle
In which 2 types of muscle are the nuclei centrally placed within the cells?
Smooth and cardiac muscle
Why is the banding pet tern of cardiac muscle not a distinct as that of skeletal muscle?
Due to the cross striations
What component of a cardiac muscle fiber is responsible for mechanical stability, transmission of electrical and chemical stimuli and contractile force?
intercalated discs
Atrial natriuretic factor (ANF) is produced in the
Atria
In the H&E stained preparation, the central region of purkinje cells appears the be empty. why is this?
Glycogen rich area– doesn’t stain
In atherosclerosis, which type of muscle tends to accumulate in the tunica intima of blood vessels?
smooth muscle
What is the most common heart arrhythmia?
A-fib
