Skeletal Muscle Perhaps the most important topic

Three types of muscle are known to exist in man and animals: skeletal muscle, cardiac muscle, and smooth muscle (9:34). Skeletal musclewhich connects to bones and jointsis typically activated by motoneurons (5:121). These muscles allow for locomotion and the performance of work (13:205). In addition, they account for over a quarter of the body's weight and the major part of its energy expenditure (5:121).

A typical skeletal muscle is composed of many muscle fibers, or skeletal muscle cells. These cells are elongate and multinuclear (5:121). Moreover, the contractile material within them shows crossstriations (5:121). Hence, skeletal muscle is one form of striated muscle (5:121).

Skeletal muscle fibers are formed by the fusion of elongated uninucleate cells called myoblasts (5:121). Mature fibers may be as long as the muscle that they comprise (5:121). Their lengths thus range up to several centimeters (12:3). Their diameters may be anywhere from 10 to 100 microns (5:121). The cell's nuclei tend to occur around the fi

. . .
ilaments in the Aband are two arrays of actin filaments which extend out to the edges of the sarcomere (12:6). An actin array in one sarcomere is linked to that in the adjacent sarcomere by a crosslinking structure termed the Zband, or Zline (12:6). Actin filaments are polar structures and the Zline serves as a structure which produces the required polarity reversal of the two actin arrays in successive sarcomeres (12:6). Hence, the Zline is the structure from which the actin molecules emanate (12:6). This allows actin filaments at both ends of a sarcomere to have the appropriate polarity for interaction with the two oppositely polarized ends of the Aband (12:6). Approximately 90 percent of muscle fiber mass can be attributed to sarcomeres (9:5). Running transversely across the fibers are the transverse, or Ttubules (9:5). Ttubules are about 400 microns in diameter (9:56). They occur at the AI junction (the outer boundaries of the Aband) of each sarcomere (9:7). Often they comprise the central tubular element of a structure known as a "triad (5:144)." A triad is made up of a transverse tubule and sarcoplasmic reticulum (SR) (9:7). In skeletal muscle cells the SR tends to be a complex, anastomosing n
. . .

Some common words found in the essay are:
Skeletal Muscle, S2 S2, Huxley Niedergerke, Hence Zline, Huxley Taylor's, Xprotein Mband, Mband Mline, Zband Zline, skeletal muscle, Journal Biomechanics, University Press, muscle fibers, actin filaments, myosin filaments, muscle fiber, myosin molecule, actin monomers, connective tissue, 123 myosin, york ny cambridge, myosin actin, ny cambridge university, cambridge university press, skeletal muscle fibers, myosin binding sites,
Approximate Word count = 2738
Approximate Pages = 11 (250 words per page)

More Essays on Skeletal Muscle Perhaps the most important topic