Which of the following molecules has a \"spring region\" that plays a major role

Question

Which of the following molecules has a "spring region" that plays a major role determining the elasticity and length-tension characteristics of skeletal muscle fibers? Actin Myosin Titin Tropomyosin Troponin Which of the following statements is/are TRUE about smooth muscle? Ca^2+ binding to troponin is required for muscle contraction Phosphorylation of myosin initiates the contractile cycle Contractile elements of smooth muscles are connected to 2-disks Contraction is modulated by Ca^2+-calmodulin binding to actin All of the above are true. Which of the following is/are a source of Ca^2+ ions for regulation of smooth muscle contraction? Voltage-dependent Ca^2+ channels in the plasma membrane IP_3 receptors in the sarcoplasmic reticulum or other internal stores TRPC3 and TRPC6 channels that become active during G-protein signaling cascades All of the above Which of the following statements is/are TRUE? During contraction, increases in intracellular Ca^2+ in smooth muscle last longer than the action potential. Spontaneous discharge of action potentials is a completely unique feature of pacemaker cells in cardiac muscle Ryanodine receptors are required for action potential discharge in muscle All of the above are true Which of the following can lead to inhibition of smooth muscle contraction? Activation of K^+ channels and cell hyperpolarization Inhibition of mobilization of internal Ca^2+ stores Activation of myosin light chain (MLC) phosphatase Localized production of NO All of the above

Explanation / Answer

Ans 19 C)titin has a spring region that plays a major role in determining the elasiticity and length -tension characterstics of skeletal muscle fibers as titin is a giant protein and function as molecular spring which is responsible for the passive elasiticity of muscle.

Related Questions

Navigate

• Browse (All)
• Browse W
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.