Q: What is the gross anatomical arrangement of a skeletal muscle?
A: An entire skeletal muscle is viewed as an organ of the solid framework. Every organ or muscle…
Q: The mechanism of muscle contraction is best explained by the sliding filament model. According to…
A: Many different forms of cell motions are caused by actin filaments, which are often linked to…
Q: How and why does an ATP solution makes the muscle fiber contract and makes it length shorter? How…
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Q: Why is it logical that there are no muscle fibers classified asslow-glycolytic?
A: There are 3 types of muscle Fibres. Type I= slow oxidative Type II=fast oxidative Type III=fast…
Q: As skeletal muscle contracts, one or more bands of the sarcomere become narrower and disappear, and…
A: When the myosin binds to the actin filaments, it forms the cross-bridge that causes a shortening of…
Q: During evolution, skeletal muscle became adapted to functional de-mands ranging from sudden,…
A: The skeletal muscles of vertebrates are composed of different types of fibers. This includes slow…
Q: What is the time relationship between a skeletal muscle fiber action potential and the resulting…
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Q: Which of the following are aspects of the structure of skeletal muscle? Select all that apply.…
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Q: How can I describe skeletal muscle contraction using the words "upper motor neuron" and "lower motor…
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Q: Is the length of muscle contraction at the beginning of tetanic contraction the same or different…
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Q: Briefly discuss the abundance of sarcoplasmic reticulum in skeletal muscle in relation to its…
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Q: a. Describe the relationship between stimulus voltage and the force of contraction b. What was the…
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Q: What cellular changes could cause the skeletal muscle to become rigid?
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Q: myofibrils or sarcomeres present in smooth muscle fibers?
A: Myofibrils are the long filaments which are arranged parallel to each other to form muscle fibers.…
Q: Compare the inner layer of smooth muscle with circumferentially running muscle cells,to the outer…
A: Internal soft organs have visceral smooth muscle in their walls (viscera). Muscle cells are joined…
Q: Why does Skeletal muscle cells contain more mitochondria than other organelles?
A: A skeletal muscle cell is a multinucleate syncytium that forms by the fusion of hundreds of myoblast…
Q: What effect does increasing the frequency of action potentials in askeletal muscle fiber have upon…
A: With alternative arrangements of light and dark band, skeletal muscles are striated muscles. They…
Q: Explain why cardiac muscle cannot undergo tetanic contractions?
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Q: Unlike skeletal muscle smooth muscle Mayer spontaneously contract when it is. What feature of smooth…
A: Smooth muscle is a non-striated muscle, divided into two groups; single unit and multiunit smooth…
Q: In muscle cells, magnesium ions compete with calcium ions for binding sites on troponin molecules.…
A: Calcium triggers contraction by reaction with regulatory proteins that in the absence of calcium…
Q: Identify the structure of the muscle fiber as indicated by the arrow in the image.
A: Muscle fibers are cylindrical muscle cells that formed by the fusion of developmental myoblasts and…
Q: Why is the innervation of single-unit smooth muscle often restricted to only a few cells in the…
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Q: under a microscope, some skeletal muscles appear white and some look red. What type of muscle…
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Q: Muscle fibers contain which of the following?
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Q: What is the fundamental contractile unit of skeletal muscle? b. What are the names of the bands,…
A: Muscle contraction occurs when sarcomeres shorten, as thick and thin filaments slide past each…
Q: Which of the following are aspects of the structure of skeletal muscle? Select all that apply.…
A: Our muscular system is made up of muscle tissues that are usually three types, skeletal muscles,…
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Q: Mention the two main proteins of the skeletal muscle with their subdivisions
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Q: What are the three muscle types shown in slide 2 (between cardiac, skeletal, and smooth)? Label A,…
A: The muscle is soft tissue and has a fibrous makeup. This tissue helps the body to maintain and aid…
Q: A.What type of contractions do skeletal muscles do? B. What type of contractions do cardiac muscles…
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Q: Which type of myosin is found in contractile bundles?
A:
Q: What are some examples of movement created by the contraction of sarcomeres of the muscle cells?
A: Muscle tissues are of three types: Skeletal muscle, cardiac muscle, and smooth muscle. Each consists…
Q: why would skeletal muscle cell need so many nuclei?
A: Skeletal muscle is a striated muscle and it usually does not contract unless stimulated by the…
Q: What is represented on the image above? (A) A cross-section of a cardiac muscle B A longitudinal…
A: Introduction Muscles are soft tissues, Many, stretchy fibers make up our muscles, muscle is a group…
Q: In smooth muscle fibers, the thin filaments attach to structures called functionally similar to Z…
A: Muscular tissue is made up of long cells of muscle fibers. It has contractile proteins that are…
Q: What is the micro anatomical arrangement of a skeletal muscle fiber cell?
A: Muscle is a soft and contractile tissue that is responsible for body movement. Muscle cells consist…
Q: How does the structure of the microfilaments allow for linear contraction of a whole muscle cells?
A: Microfilaments are little, string like protein fibres with a diameter of 3-6 nm. They are mostly…
Q: Explain why myosin II in a sarcomere can produced force only for that sarcomere contraction and not…
A: SARCOMERE It is the basic structural and functional unit of muscle tissue. COMPONENTS: Each…
Q: What is elastic fibers ?
A: Connective tissue is the most abundant and widely distributed type of tissue in higher animals,…
Q: If a muscle is contracted and shortening, what happens to the following: (a) width of the A band,…
A: A myofibril has light bands (A-bands or anisotropic bands) and dark bands (I-bands or isotropic…
Q: While the sarcoplasmic reticulum of muscle was first described by nineteenth-century microscopists,…
A: The structure of the sarcoplasmic reticulum is a little different from the normal endoplasmic…
Q: Outline the role of calcium ions on muscle contraction during a biceps curl. In your answer: A)…
A: The muscle cells possess electrical excitability and contraction properties. Their contraction…
Q: Name the characteristics of muscles. Name the muscle functions. Name the types of muscles and…
A: As per our honor code we are authorized to answer only one question at a moment. In case you need…
The structural organization of muscle fibers makes it possible to produce contractile force.
a. What is the fundamental contractile unit of skeletal muscle?
b. What are the names of the bands, lines and zone of the contractile unit of skeletal muscle?
c. Each of the contractile unit region names in (b) contains a letter. What does each of these letters stand for?
d. What changes occur in the contractile unit regions during contraction?
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- a. What is the fundamental contractile unit of skeletal muscle? b. What are the names of the bands, lines and zone of the contractile unit of skeletal muscle? c. Each of the contractile unit region names in (b) contains a letter. What does each of these letters stand for? d. What changes occur in the contractile unit regions during contraction?In muscle cells, magnesium ions compete with calcium ions for binding sites on troponin molecules. If a person has too high a concentration of magnesium ions in the blood, magnesium ions can prevent calcium ions from binding troponin. A) What effect would this have on muscle contraction (strengthen, weaken, or no effect)? B) Use your knowledge of how muscle fibers contract to explain your answer in part A.The organization of myosin in smooth and striated muscle: A.) differ because smooth muscle lacks sarcomeres B.) is identical but the organization of actin is different C.) is identical but the isoforms of myosin differ D.) differ because striated muscle myosin forms filaments but smooth muscle myosin does not ATP is required for: a.) the phosphorylation of the myosin head in smooth muscle b.) the movement of tropomyosin on the actin filament c.) the swing of the myosin lever arm d.) A and B e.) tethering troponin I to troponin C
- Which of the following is true concerning the role of Calcium in the contraction of muscle- cells? 23. A. skeletal muscle cells require an extracellular inward-Calcium-current to stimulate the burst of Calcium from the sarcoplasmic reticulum. B. smooth muscle cells require an extracellular inward-Calcium-current to stimulate the burst of Calcium from the sarcoplasmic reticulum. C. cardiac muscle cells require an extracellular inward-Calcium-current to stimulate the An burst of Calcium from intracellular stored-Calcium-organelles. D. No type of muscle cell requires an extracellular inward-Calcium current for normal contractile-function.Cardiac and skeletal muscle are both “striated” types of muscle and yet they have very distinct functional characteristics. a) Skeletal muscle functions as discrete motor units and the cardiac muscle works as a functional syncytium. Define the italicized terms in the previous sentence, explain their importance, and describe the cellular features that underlie these functional differences. b) Cardiac muscle exhibits automaticity, while excitation of skeletal muscle is neurogenic. Define the italicized terms and provide a brief explanation of mechanisms underlying each.A motor unit from a skeletal muscle contains 1500 muscle fibers. Would this muscle be involved in fine, delicate movements or in powerful, gross movements? Explain.
- Skeletal muscle has several distinct fiber types. Type I is used primarily for aerobic activity, whereas type IIb is specialized for short, intense bursts of activity. How could you distinguish between these types of muscle fiber if you viewed them with an electron microscope?Considering the Length-Tension Relationship of skeletal muscle fibers, over stretching a muscle fiber or not stretching a muscle fiber enough, results ina decrease in force developed (during contraction) because: 27. A. An "over-stretched" muscle fiber or an “under-stretched" muscle fiber will not allow Calcium, from the sarcoplasmic reticulum, to adequately diffuse into the cytoplasm. B. An "over-stretched" muscle fiber or an "under-stretched" muscle fiber will not allow an optimum amount of contact and overlap for the contractile proteins. C. An "over-stretched" muscle fiber or an“under-stretched" muscle fiber will not allow the Action Potential to reach the troponin-activation channels. D. An "over-stretched" muscle fiber or an "under-stretched" muscle fiber will not allow the Sodium current to depolarize the membrane. Teurons toa) Describe how the isolated muscle behaved as it was stretched progressively. b) What effect does stretching the muscle have on contraction strength? Is this effect linear? c) What stretch resulted in the highest contraction force? What happens to the muscle at the highest stretch levels?
- Skeletal muscle fibres are very metabolically active and are adapted to create a lot of ATP from aerobic cellular respiration. Additionally, cells require other things to stay alive. Explain how the following three organ systems contribute to allowing a muscle cell to carry out its roles: a) Respiratory system b) Cardiovascular system c) Gastrointestinal system asap please.Striated and smooth muscle activation differ because: a.) striated muscle activation is due to structural changes in the actin thin filament while smooth muscle activation requires structural changes in the myosin thick filament b.) striated muscle excitation is voltage dependent and smooth muscle is not c.) striated muscle activation requires calcium but smooth muscle does not d.) troponin C binds calcium in striated muscle while tropomyosin binds calcium in smooth muscle e.) A & DWith regard to muscle contraction, which of the following is an INCORRECT statement with regard to the interactions of filaments that occur in the sarcomere? A. When muscles are relaxed tropomyosin blocks binding sites on actin subunits, which keeps cross-bridges from forming. B. The myosin heads conduct a power stroke motion to slide when bound to actin, to move the "thin" filaments towards the center of the sarcomere. C. During contraction, actin subunits are removed from the ends of the "thin" filaments to shorten actin polymers, thus reducing the length of the sarcomere. D. "Thick" filaments are anchored at the M-line, while "thin" filaments are anchored at the Z-line. E. Numerous myosin heads engage with the actin filaments simultaneously, such that there is no back-slipping during the contraction process.