Which statement about striated skeletal muscle is true?   A. The tension generated by a muscle is invariable.   B. Mechanical summation of twitches in a muscle fiber leads to a graded increase in the tension that is above that generated by a single twitch.   C. A single action potential arriving at the neuromuscular junction is not sufficient to cause a muscle fiber to twitch.   D. Muscle twitches are able to mechanically sum when Ca2+ is quickly and completely removed from the sarcoplasm between action potentials.   E. An action potential in the muscle cell activates contraction by releasing Na+ into the sarcoplasm.

Q: The cross bridges of the sarcomere in skeletal muscle are made up of                 A. myelin.…

A: Introduction:-  Muscles are delicate tissue present in most animals . These contain filaments like…

Q: The Sarcomere 2 Thin filaments are often named for which protein? a. actin b. myosin c. troponin d.…

A: The sarcomere is the smallest functional unit of a skeletal muscle fiber. It is a highly organized…

Q: Calcium plays a crucial role in the contraction of skeletal muscles. i. Where is calcium stored…

A: The sliding filament theory was proposed as an explanation for muscle contraction. It is based on…

Q: This player in smooth muscle contraction is analogous to troponin in skeletal and cardiac muscle…

A: The muscular system is one of the major organ systems in the body. It contains three forms of…

Q: Which item is biggest? A. myosin head B. myofibril C. troponin D. sarcomere

A: Muscles are compact structures made up of highly tensile , strong, long, multinucleated cells called…

Q: What role (function) does calcium have within a muscle fiber? a. trigger muscle potentials along…

A: Calcium is present in the sarcoplasmic reticulum until and unless it is released by the stimulus. It…

Q: When we increased the frequency, why could we see an in increase in the force of contraction? Is it…

A: An action potential can be defined as a rapid increase and decrease in the membrane potential of the…

Q: Which is the first step in the contraction phase of the excitation-contraction coupling? a. Action…

A: Excitation-contraction coupling commences with depolarization and stretch of an AP along the…

Q: Which statement(s) about human neuromuscular innervation is/are true? A. A single spinal motor…

A: A chemical synapse between a motor neuron and a muscle fibre is known as a neuromuscular junction.…

Q: Which characteristic or component is NOT shared by skeletal muscle and cardiac muscle? I. Electrical…

A: There are three types of muscles in the body. Smooth muscles and cardiac muscles are involuntary…

Q: Muscle fibers contractions differ with regard to tension and shortening. When a muscle Fiber begins…

A: Isometric and isoconcentric

Q: What structure on a muscle fiber is composed of largely two varieties of contractile proteins--actin…

A: Muscle fibre is a single muscle cell. These muscles help control our bodily movement.

Q: if, in a laboratory, a skeletal muscle cell receives a single stimulus to contract, it produces a…

A: As per our honor code, we are authorized to answer only one question at a moment. So, we are…

Q: Which of the following is true concerning the role of Calcium in the contraction of muscle- cells?…

A: A muscle is a smooth tissue in animals. On the basis of structure, contractile properties and…

Q: During which phase of the crossbridge cycle is ATP split into ADP and Pi? A. Immediately preceding…

A: Cross bridge cycling refers specifically to the action of the cross-bridge, that being the head and…

Q: During which phase of a twitch in a muscle fiber istension the greatest?a. resting phaseb.…

A: The phenomenon of lifting or moving an object (load) involves the sarcomeres present in the muscle…

Q: What might happen if skeletal muscle lacked tropomyosin?   A. The striation pattern would…

A: Myogenesis is the process of formation of muscles from the mesodermal layer of embryonic germ cells.…

Q: Put the following in order to accurately follow the sequence of events associated with muscle fiber…

A: Relaxing of muscle filaments starts with the motor neuron, which stop delivering its compound sign,…

Q: Myosin binds to actin, then bends. What is ATP needed for next? A. to pump the Ca++ “keys” back into…

A: D option is the correct statement.

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.