Skeletal Muscle Research Paper

Improved Essays
Of the three types of muscle cells, skeletal muscle cells are the most recognizable as muscles because skeletal muscles are the type used in voluntary movement. Skeletal muscles cells are some of the most distinct differentiated cells in the human body, this distinction is likely because of the clear and specific purpose in the body of being the source of contractions that allow voluntary movement. I chose skeletal muscle cells because it’s fascinating to me how movement of the body is such a smooth function and how structure of the skeletal muscles cell and the mechanism of contraction allow this vital operation of life to be used in all manners from fine touch to powerful force.
Muscles can be made up of 3 types of cells: skeletal, smooth,
…show more content…
Skeletal muscle cells have what is known as striations or stripe like appearance of the cell body. Skeletal muscle cells are multinucleated often because of their large size another distinction of muscle fibers. Skeletal muscle cells have a significant number of mitochondria this is a result of the large amount of energy that muscle contraction and movement use. Muscles build together much like cable or rope, muscles can be separated into bundles of fascicles and fascicles can be separated into bundles of muscles fibers and finally muscle fibers can be separated into bundles of myofibrils, which are another unique structure of skeletal muscle cells. This bundling allows muscles to have great strength in their …show more content…
The SR is extensive and covering all the myofibrils this allows fine control of contractions of the myofibrils due to depolarization only affecting the targeted areas since the SR release of calcium ions is the key to muscle contraction. Myofibrils are protein bundles containing actin and myosin. Actin (thin) and myosin (thick) make up a unit of skeletal muscle cell called a sarcomere, the main unit of contraction in skeletal muscle cells. The patterns of sarcomeres make up the striations or the stripe like feature of the cell. The actin and myosin in the sarcomere use what is known as the sliding filament theory as means of causing the contractions of muscle. Myosin slides along actin filaments to contract a sarcomere as the number of sarcomeres contracting increases the muscle contracts stronger and stronger vice-versa as more sarcomeres relax the muscle contraction grows weaker and weaker. A sarcomere contraction can only occur when calcium ions from the SR that are released by action potentials from nerve fibers bind to the protein troponin that is associated with tropomyosin this calcium binding

Related Documents

  • Decent Essays

    Unit 3 Muscle Lab

    • 248 Words
    • 1 Pages

    There are three types of muscles in the human body: cardiac muscle, smooth muscle and skeletal muscle. For the purpose of our lab we will be focusing only on skeletal muscle. Skeletal muscle is the only voluntary muscle tissue found in the human body. They're attached to bones by tendons and are responsible for all the movements that are consciously controlled such as writing, walking, running, etc. [1].…

    • 248 Words
    • 1 Pages
    Decent Essays
  • Improved Essays

    Grip Strength Exercise

    • 522 Words
    • 3 Pages

    These muscle fibers are composed of myofibrils, which not only give the muscle its striated appearance but also are also composed of contractile proteins known as actin (thin filaments) and myosin (thick filaments). Each actin protein has a binding site for myosin, which is regulated by two proteins known as Tropomyosin and Troponin. Both of these regulator proteins inhibit the binding of myosin to actin by overlapping the binding sites in a confirmation that could be described as a ribbon (Tropomyosin) and a thumbtack (Troponin). Each skeletal muscle is then divided and encapsulated by three difference layers of connective tissue. The first of these layers enclosed the whole skeletal muscle and is known as the epimysium, the second layer of connective tissue called the perimysium encloses each fascicle and finally the last layer of connective tissue which encapsulates each muscle fiber, which is known as the…

    • 522 Words
    • 3 Pages
    Improved Essays
  • Improved Essays

    The firing of gamma motor neurons in sync with alpha motor neurons pulls muscle spindles, innervating the muscle. The spindle is innervated by type Ia sensory fiber that goes on to synapse with alpha motor units. Therefore, there are more motor units being put to work and the type 1a afferents maintain their sensitivity.…

    • 399 Words
    • 2 Pages
    Improved Essays
  • Improved Essays

    Muscles Lab Report

    • 786 Words
    • 4 Pages

    However, there are a great deal of muscles and nerves in the forearm. When a nerve impulse transmission to synaptosomes induced depolarization, allows calcium ions to enter the cell membrane, the synaptic vesicles move forward and release acetylcholine (ACH). ACH combined with membrane receptors on the endplate cause electronic potentials, potassium and sodium ions exchanging start to spread both sides of muscle cell membrane to form the action potentials, and long with the cell membrane so that both sides of the terminal cistern will release Ca2+, Ca2+ and troponin binding to change tropomyosin, let actin exposed binding site to the cross bridge.…

    • 786 Words
    • 4 Pages
    Improved Essays
  • Improved Essays

    Skeletal Muscle System

    • 413 Words
    • 2 Pages

    and then travels to the end of the motor neuron. The motor end plate is protected by a phospholipid bilayer that has acetylcholine receptors that allow acetylcholine to flow from the synaptic cleft into the motor end plate. When acetylcholine attaches to the acetylcholine receptors, it activates sodium channels to open. Sodium channels open and let positively charged sodium ions rapidly into the motor end plate, while potassium ions are slowly kicked out of the charged environment in the motor end plate. This is the first step of skeletal muscle fiber excitation, where our nervous system sends a nerve signal to our muscle fibers to go from a relaxed position to a contracted position by producing tension on the skeletal muscle of an area to cause the body to move.…

    • 413 Words
    • 2 Pages
    Improved Essays
  • Decent Essays

    Muscle Reflex Lab

    • 198 Words
    • 1 Pages

    The muscle strength and reflex lab uses the involvement of two subjects to demonstrate the electrical properties of muscles and their motor neurons. With the relative strength and electrical activity of the dominant forearm, the observed data showed how the dominant forearm will average a higher force due to the amount of strength that arm may or may not have, and the amount of receptors that contract in unison. Supporting our second hypothesis, the non-dominant forearm resulted in a higher fatigue rate than the dominant forearm. This demonstration shows how the dominant arm with larger diameter fibers will be more likely to have more mitochondria and myofibrils causing the longer fibers to fatigue. There may also be a case where the dominant…

    • 198 Words
    • 1 Pages
    Decent Essays
  • Improved Essays

    Thus, when the ryanodine receptors are activated it allows more calcium to leave the SR and into the cytoplasm. Calcium is exceedingly important in muscle function, because it binds to a component on the actin called the troponin. A muscle fiber is made up of countless sarcomeres that contains myosin and actin filaments. To have a contraction, myosin and actin must form a cross-bridge and induce a power stroke. To phenomenon occurs when two important molecules are present, calcium and ATP Myosin is a thick filament that attaches to a binding site on the actin, which is a thin filament.…

    • 555 Words
    • 3 Pages
    Improved Essays
  • Superior Essays

    Introduction Some people believe that we have only one type of muscle in our bodies that help us with all different types of tasks, however; not only do our bodies have different muscle types, they also contain different muscle fibers that are used for different activities. Skeletal muscle contain three types of muscle fibers: slow twitch, fast twitch oxidative, and fast twitch glycolytic. Most muscles in our bodies have different combinations of these muscle fibers, although our body recruits different muscle fibers for different activities. The first muscle fiber to be recruited are slow twitch fibers, are also known as Type I. “Slow twitch muscle fibers are the smallest in diameter, contain the least amount of actin and myosin, and allow…

    • 2096 Words
    • 9 Pages
    Superior Essays
  • Superior Essays

    Explain the significance of the thickness of the left ventricular wall. The left ventricle works harder as it pumps blood to the systemic circuit, not just to the pulmonary portions as the right ventricular does. Therefore, the left ventricular walls are thicker, to support the hard work that it has to do throughout the body (Martini & Nath,2014 p.685) The major coronary vessels are on the surface of the heart.…

    • 947 Words
    • 4 Pages
    Superior Essays
  • Great Essays

    Muscle Contraction Essay

    • 1101 Words
    • 5 Pages

    Each molecule is described as being “shaped like two golf clubs twisted together” (Tortora and Derrickon, 2011), with the tail facing the M line that appears at the centre of the sarcomere. Actin is thinner and its molecules come together in a twisted helix shape to form the thin filaments that come from the Z disc of the sarcomere. What is important to note here is that every actin molecule has its own myosin binding site. This means that the myosin heads, the “golf club” like structures depicted earlier, can attach themselves to the actin – it is this action that causes muscle contraction as we shall see.…

    • 1101 Words
    • 5 Pages
    Great Essays
  • Improved Essays

    Smooth muscle cells are spindle-shaped and can contract. The contraction of smooth muscle can be stimulated by chemicals of nearby motor neurons. Smooth muscle can regenerate the most out of the three types of muscle. Some smooth muscle can be under your control but it can be painful. Cardiac muscle is only found by the heart.…

    • 425 Words
    • 2 Pages
    Improved Essays
  • Improved Essays

    Knee Joint Research Paper

    • 1146 Words
    • 5 Pages

    Skeletal muscle tissue is a voluntary striated muscle tissue that consists of bundles of muscle fibers; each muscle fiber is a long, multi-nucleated cell that contains myofibrils, which account for the visual striations as well as the contractile force of muscular tissue. Myofibrils are made up of a thick filament and a thin filament; the thick filament is myosin and the thin filament is a complex of actin, troponin, and tropomyosin (3)(4). Using calcium and ATP, the thick and thin filaments interact with each other resulting in a power stroke and a shortening of the sarcomere, the skeletal muscle fiber's contractile unit (4). The shortening of multiple sarcomeres in multiple muscle fibers results in the overall contraction of the muscle. Due to the origin and insertion of the muscles around the knee joint, this contractile force allows extension and flexure of the bones that meet at the knee…

    • 1146 Words
    • 5 Pages
    Improved Essays
  • Great Essays

    GTOs play an important protective role for the muscle system since they sense changes in muscle tension. Because of this they can protect the muscle from excessive tension by causing the muscle to relax thus prevent injury and damage of muscles. Essay Questions 1. The sliding filament theory is how muscles are able to create force when having the thick (myosin) filaments slide past the thin (actin) filaments during muscle contraction overlapping in ratchet-like manner, this causes the sarcomere to contract, while staying at the same length. Nerve impulse causes the release of Ca+2 enabling the myosin bridges to bind with actin.…

    • 1024 Words
    • 5 Pages
    Great Essays
  • Improved Essays

    What Is Muscle Damage?

    • 1321 Words
    • 6 Pages

    Muscle can be damaged whether it be from sports injuries or other accidents. When this muscle damage occurs, the body responds accordingly in order to regenerate this lost or injured muscle. There are three main steps that are necessary in order for this renewal to occur. These steps include inflammation, revascularization/satellite cell differentiation, and innervation. (Grounds, 2011)…

    • 1321 Words
    • 6 Pages
    Improved Essays