A sarcomere is best described as
A sarcomere (Greek sarx flesh, meros part) is the basic unit of striated muscle tissue. Skeletal muscles are composed of tubular muscle cells (myocytes called muscle fibers) which are formed in a process known as myogenesis. Muscle fibers are composed of tubular myofibrils.he relationship between the proteins and the regions of the sarcomere are as follows: 1  Actin filaments, the thin filaments, are the major component of the I-band and extend into the A-band. 2  Myosin filaments, the thick filaments, are bipolar and extend throughout the A-band. The myosin head also binds to ATP, which is the source of energy for muscle movement. Myosin can only bind to actin when the binding sites on actin are exposed by calcium ions. Actin molecules are bound to the Z line, which forms the borders of the sarcomere.Other bands appear when the sarcomere is relaxed. A muscle fiber from a biceps muscle may contain 100,000 sarcomeres.he relationship between the proteins and the regions of the sarcomere are as follows: 1  Actin filaments, the thin filaments, are the major component of the I-band and extend into the A-band. 2  Myosin filaments, the thick filaments, are bipolar and extend throughout the A-band. Myosin has a long, fibrous tail and a globular head, which binds to actin. The myosin head also binds to ATP, which is the source of energy for muscle movement. Myosin can only bind to actin when the binding sites on actin are exposed by calcium ions.est Answer: i would choose d Myofibrils are composed of repeating sections of sarcomeres, which appear under the microscope as dark and light bands. The actin and myosin interact and the actin is pulled over the myosin, shortening the sarcomere. The sliding-filament theory is the description of the muscle anatomy from the muscle fiber down to the structures within the sarcomere.T tubules are an invagination of the ________.myosin. muscle fibers.he actin and myosin interact and the actin is pulled over the myosin, shortening the sarcomere. The sliding-filament theory is the description of the muscle anatomy from the muscle fiber down to the structures within the sarcomere. T tubules are an invagination of the ________. myosin. muscle fibers. A sarcomere is best described asa unit within a myofibril. It is a  basic unit of a muscle. It comes from the Greek word sarx which  means flesh and meros which means pa … rt.he boundary of the sarcomere are the Z lines. Thin filaments extend from the Z li … nes and overlap with thick filaments in the middle of the sarcomere. Answers. Best Answer: i would choose d Myofibrils are composed of repeating sections of sarcomeres, which appear under the microscope as dark and light bands.Sarcomeres are composed of long, fibrous proteins that slide past each other when the muscles contract and relax.est Answer: i would choose d Myofibrils are composed of repeating sections of sarcomeres, which appear under the microscope as dark and light bands. A sarcomere consists of thin and thick filaments arranged so they can slide over each other. The boundary of the sarcomere are the Z lines. Thin filaments extend from the Z li … nes and overlap with thick filaments in the middle of the sarcomere. The I band is on each side of the Z line where only thin filaments occur.he boundary of the sarcomere are the Z lines. Thin filaments extend from the Z li … nes and overlap with thick filaments in the middle of the sarcomere. Once innervated, the protein filaments within each skeletal muscle fiber slide past each other to produce a contraction, which is explained by the sliding filament theory. The contractions that is produced can be described as a twitch, summation, or tetanus, depending on the frequency of action potentials.uscle contractions can be described based on two variables: length and tension. A muscle contraction is described as isometric if the muscle tension changes but the muscle length remains the same. In contrast, a muscle contraction is isotonic if muscle length changes but the muscle tension remains the same. Thick filaments contain myosin, while thin filaments contain actin. Actin and myosin collectively are referred to as the contractile proteins, which cause muscle shortening when they interact with each other.hick filaments contain myosin, while thin filaments contain actin. Actin and myosin collectively are referred to as the contractile proteins, which cause muscle shortening when they interact with each other. The boundary of the sarcomere are the Z lines. Thin filaments extend from the Z li … nes and overlap with thick filaments in the middle of the sarcomere.The I band is on each side of the Z line where only thin filaments occur.he boundary of the sarcomere are the Z lines. Thin filaments extend from the Z li … nes and overlap with thick filaments in the middle of the sarcomere.
A unit within a myofibril.