Preview

Smooth Muscle Contraction

Good Essays
Open Document
Open Document
213 Words
Grammar
Grammar
Plagiarism
Plagiarism
Writing
Writing
Score
Score
Smooth Muscle Contraction
Relaxation of the smooth muscle takes place due to the absence of the contractile stimulus or through the presence of a substance, which induces the inhibition of the mechanism that initiates contraction. For this process to take place, low levels of intracellular Ca2+concentration are required along with high MLC phosphatase activity. Reduction in calcium release from the SR or reduction of calcium entry into the cell can cause this reduction in the phosphorylation of MLC. There are several mechanisms involved in the removal of cytosolic calcium. ATP hydrolysis determines the level of Ca2+ uptake in which the phosphorylation of CaMg-ATPase (also found in the plasma membrane) leads to two Ca2+ ions to bind and is transferred to the luminal
Continue Reading
View Writing Issues

You May Also Find These Documents Helpful

  • Good Essays

    unit 10 review
    • 1120 Words
    • 5 Pages

    unit 10 review

    d. the relationship between excitation at the sarcolemma and release of calcium ions from the sarcoplasmic…

    • 1120 Words
    • 5 Pages
    Good Essays
    Read More
  • Satisfactory Essays

    508DiscussionGroupCollaboration
    • 765 Words
    • 5 Pages

    508DiscussionGroupCollaboration

    Directions: If you are unable to attend a live collaboration session, this activity will allow you to get credit for the Segment 2 Collaboration Project. Fill out the RED sections of this activity sheet.…

    • 765 Words
    • 5 Pages
    Satisfactory Essays
    Read More
  • Good Essays

    Tension In Muscle Contractions
    • 469 Words
    • 2 Pages

    Tension In Muscle Contractions

    Muscle contractions happen when muscle fibers are stimulated, which can cause one of many types of contractions. Isometric contractions, which means that tension happens in the muscle but there is no change in muscle length, therefore there is no movement of the muscle itself. An example of Isometric contractions would be strength training, such as holding a weight still, which happens in the biceps brachii. The biceps brachii the gets more tension, but the muscle length stays the same. As for isotonic contractions, which means that tension is in the muscle while there is a change of length, can be split into two types: Concentric contraction, in which the tension causes the muscle to shorten, and eccentric, in which the tension causes the muscle to elongate.…

    • 469 Words
    • 2 Pages
    Good Essays
    Read More
  • Good Essays

    Malignant Hyperthermia
    • 3105 Words
    • 13 Pages

    Malignant Hyperthermia

    In muscle contraction calcium is released into the cell as a key component in muscle contraction. In MH there is a problem with calcium reuptake. Intracellular calcium increases up 500 fold leading to substained muscle contraction. The cell incurs a severe oxygen debt, the constant demand for ATP leads to glycolysis and subsequent to lactic acidosis. Eventually this lead to membrane instability, cell rupture and rhabdomyolysis. (http://www.mhaus.org)…

    • 3105 Words
    • 13 Pages
    Good Essays
    Read More
  • Good Essays

    Activity 1: The Muscle Twitch And Latent
    • 2408 Words
    • 10 Pages

    Activity 1: The Muscle Twitch And Latent

    Define the terms skeletal muscle fiber, motor unit, skeletal muscle twitch, electrical stimulus, and latent period. Skeletal Muscle Fiber: Skeletal muscle cells that are composed of hundreds to thousands of individual cells that produce muscle tension. These fibers are what move our bodies and generate muscle tension/force that enables us to have manual dexterity.…

    • 2408 Words
    • 10 Pages
    Good Essays
    Read More
  • Powerful Essays

    Temporal summation and Muscle tension
    • 1976 Words
    • 7 Pages

    Temporal summation and Muscle tension

    Active sites on the actin filament available for bonding with myosin heads only become exposed in the presence of calcium ions (Ca2+) (Orentlicher & Gersho 1977). Hence sarcoplasmic concentration of Ca2+ must increase in order for the cross bridge cycle to commence. This is achieved through excitation-contraction coupling – a series of events that link the depolarisation of the muscle surface…

    • 1976 Words
    • 7 Pages
    Powerful Essays
    Read More
  • Good Essays

    Muscle Contraction Lab Report
    • 1245 Words
    • 5 Pages

    Muscle Contraction Lab Report

    In the muscle fibre the immediate steps leading to contraction involve action potentials and calcium. T tubules conduct action potentials into the interior of the fibre. Dihydropyridine (DHP) receptors on the T tubule membrane release calcium when an action potential arrives. This stimulates the Ryanodine receptors (RyR) on the sacroplasmic reticulum to release larger amounts of calcium. Troponin is wrapped around actin and prevents myosin from binding to it. Calcium diffuses into the myofibrils where it binds to troponin causing a conformational shape change, revealing the myosin-binding site and facilitating myosin-actin interaction (Astrand & Rodahl, 2003).…

    • 1245 Words
    • 5 Pages
    Good Essays
    Read More
  • Good Essays

    Skeletal Muscle Contraction
    • 656 Words
    • 3 Pages

    Skeletal Muscle Contraction

    When this calcium is released, binding sites on the thin filaments become available that allow the thick filaments to bind and pull the thin filaments toward the center of the sarcomere, generating…

    • 656 Words
    • 3 Pages
    Good Essays
    Read More
  • Powerful Essays

    Bado's Hypocalcemia Case Study Answers
    • 446 Words
    • 2 Pages

    Bado's Hypocalcemia Case Study Answers

    c. Hypercalcemia affects the skeletal muscles because it increases the concentration of calcium outside of the cell which raises the threshold potential and lowers the cells excitability.…

    • 446 Words
    • 2 Pages
    Powerful Essays
    Read More
  • Good Essays

    Muscle Contraction/Excitation
    • 456 Words
    • 2 Pages

    Muscle Contraction/Excitation

    (1)First an action potential comes down the somatic motor neuron axon and stimulates an action potential on the sarcolemma of the muscle fiber (cell). (2)Then the action potential travels down the T tubules and (3) stimulates the sarcoplasmic reticulum to release calcium into the sarcoplasm. (4)Calcium then binds with the tropomyosin and moves it out of the way exposing the binding sites on the actin. (5)The binding sites are now free for the myosin to attach to them. (6)When the myosin attaches to the actin it forms a cross bridge. At this point we burn an ATP in order for the myosin to grab an actin. (7)The myosin then pulls on actin causing contraction. This is called the “power stroke”.…

    • 456 Words
    • 2 Pages
    Good Essays
    Read More
  • Satisfactory Essays

    Muscles and the Sliding Filament Theory
    • 469 Words
    • 4 Pages

    Muscles and the Sliding Filament Theory

    The calcium binds to troponin, changing its shape and so moving tropomyosin. This exposes the active binding site of the Actin.  The Myosin filaments can now attach…

    • 469 Words
    • 4 Pages
    Satisfactory Essays
    Read More
  • Good Essays

    Muscle Contraction
    • 886 Words
    • 4 Pages

    Muscle Contraction

    The two main processes involved in muscle contraction are cross-bridge cycling and the length-tension relationship, which normally function to maximize contraction in the muscle. Beginning with the activation of a motor unit, the ions flow from the motor unit towards the muscle fibers that it innervates by the motor neuron in the same way as a normal muscle would. However since the tissue is damaged, the force that is generated by these muscle fibers will not be as great, leaving the fibers less effective. Now, there is a situation in which the myosin head is damaged and there are less actin binding to less myosin effecting the force production. The length tension relationship is dependent on the number of cross-bridges that are formed, which decreases when they are not generating at the usual amount. In relation to the length-tension relationship, when a muscle is contracting at an angle in which the muscle should have greater force, it will not because of the lack of actin-myosin overlap. So when the myosin head pivots, there are now less pivoting myosin heads. A major cause of this deviation is due to a lack of calcium flooding into the muscle cell. If there is not enough calcium for the troponin to bind to in order to expose the…

    • 886 Words
    • 4 Pages
    Good Essays
    Read More
  • Good Essays

    Outline the Differences Between the Excitation-Contraction Coupling Mechanism Between Skeletal and Cardiac Muscles.
    • 596 Words
    • 3 Pages

    Outline the Differences Between the Excitation-Contraction Coupling Mechanism Between Skeletal and Cardiac Muscles.

    The skeletal muscles and cardiac muscles differ mainly in mechanisms by which the depolarisation in the membrane leads to the release of Ca2+. In the skeletal muscle, the T-tubule membrane is coupled closely to the sarcoplasmic reticulum via the L-type calcium channel and the ryanodine receptor. However, in the cardiac muscle the Ca2+ enters via voltage-gated calcium channels which initiate a regenerative release, through activation of the Ca2+ sensitive ryanodine receptor and this initial entry triggers further release from the sarcoplasmic reticulum. (Rang and Dale, 2003)…

    • 596 Words
    • 3 Pages
    Good Essays
    Read More
  • Satisfactory Essays

    Muscle Contraction Research Paper
    • 259 Words
    • 2 Pages

    Muscle Contraction Research Paper

    Neuronal signaling in muscle contraction is triggered when an action potential reaches the neuromuscular junction. At this junction, acetylcholine (ACh) is the main neurotransmitter. Packaged in vesicles, ACh fuses with the neuron’s membrane and is released into the synaptic cleft. ACh diffuses toward the motor end plate and bind to the neurotransmitter receptor on it. The muscle fiber is then triggered to produce an action potential of its own that spreads through the muscle’s T-tubules. The sarcoplasmic reticulum in the muscle releases Ca+ into the cytosol through various ion channels. After the sarcoplasmic reticulum has released Ca+, the Ca+ binds to molecules of troponin. This binding…

    • 259 Words
    • 2 Pages
    Satisfactory Essays
    Read More
  • Satisfactory Essays

    Abbreviated Progressive Muscle Relaxation
    • 278 Words
    • 2 Pages

    Abbreviated Progressive Muscle Relaxation

    "Abbreviated progressive muscle relaxation (APMR) is a shortened version of Jacobson's (1939) original technique, designed to induce feelings of deep relaxation by systematically tensing and relaxing 16 muscle groups and by learning to focus on and discriminate between the resulting sensations of tension and relaxation." It has been proven that APMR has reduced levels of anxiety and stress, while increasing positivity. APMR has also has also relieved headaches caused by tension in some people (Chellew et al. 538). A study conducted by Joana Fornes-Vives was done to look at the responses to APMR in college students. Fifty percent of college students report that going to a university is a stressful time of their lives. Dealing with due dates…

    • 278 Words
    • 2 Pages
    Satisfactory Essays
    Read More

Related Topics