Concerning the cross-bridge (CB) power stroke, it is true that: O a. All of these O b. In concentric contractions, the CB power stroke pulls the actin filament toward the center of the sarcomere, causing sarcomere shortening O c. In isometric contractions, the CB power stroke pulls the actin filament straight down, preventing shortening or lengthening O d. In eccentric contractions, the CB power stroke pushes the actin filament away from the center of the sarcomere, causing sarcomere lengthening

Q: While running, we expect the amount of calcium outside the sarcoplastic reticulum, inside the muscle…

A: In this question asked about calcium level in muscle during running.  Detailed solution in step 2.

Q: During sarcomere contraction, which of the following does NOT change length? A the distance between…

A: 1. troponin, tropomyosin and myosin After the release of calcium from the sarcoplasmic reticulum,…

Q: In relaxed muscle, the myosin-binding site on adin is blocked by ?

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Q: Hill's equation gives a relation between muscle contraction rates νν and muscle tension TT…

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Q: Explain in detail how the of relaxion towards Smooth muscle contraction is done by the antagonsists…

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Q: Why is it important to remove acetylcholine from its binding to acetylcholine receptors once the…

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Q: Describe the structural features of a neuromuscular junction andthe role of acetylcholine in…

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Q: Acetylcholine is necessary for the depolarization of skeletal muscle cells. Which of the following…

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Q: To demonstrate muscle fatigue, a student held an 8 lb dumbbell in her hand and abducted her arm…

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Q: Myofibis in muscle fibres are made up of repeating units of dark and light bonds called

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Q: Explain the specific role of acetylcholine (ACh) instimulating a muscle fiber to contract.

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Q: What effect does increasing the frequency of action potentials in askeletal muscle fiber have upon…

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Q: Determine the isoelectric point of myofibrillar proteins here in this experimental data

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Q: Predict the consequence if presynaptic action potentials in an axonrelease insufficient…

A: Acetylcholine is an organic chemical that functions in the brain and body of many types of animals…

Q: Describe the effect of increasing the load on a skeletal muscle fiberon the velocity of shortening?

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Q: Briefly describe why contraction of the muscle cell is called “sliding filament theory” (what is…

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Q: Explain the intracellular mechansim of smooth muscle relaxation of agaonist such as mepyrimine and…

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Q: Based on your understanding of skeletal muscle fiber physiology, which of the following processes is…

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Q: If ligand-gated K+ channels were to open in an unstimulated muscle fiber,how would this affect the…

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Q: Describe in details the biochemical and mechanochemical series of events that enables motor neurons…

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Q: explain why the I band and H zoneshorten during muscle contraction, while the length of theA band…

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Q: Describe in detail the events at the neuromuscular junction and how these events allow for the…

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Q: Explain the requirements for Ca2+ and ATP in muscle contraction and relaxation.  Remember that…

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Q: Draw a graph of the force–shortening velocityrelationship of striated muscle.

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Q: Describe and explain the sliding filament model of contraction. Be sure to include in your response…

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Q: 4. As skeletal muscle shortens with contraction, the length of the I band remains constant as the…

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Muscle Action

A change in the body or a bodily organ as a result of its functioning is referred to as an action. Muscle action can be defined as the specific movement of a bodily part generated by the contraction of a muscle. The muscle proteins actin and myosin are the important contractile proteins involved in muscle action. Muscle contraction, in addition to movement, serves several other important functions in the body, including posture, heat generation, and joint stability. Muscle contraction maintains posture, which includes standing and sitting.