Which of the following are aspects of the structure of skeletal muscle? Select all that apply.       --They are cylindrical cells called muscle fibers that have multiple nuclei.   --Skeletal muscle has more mitochondria than other types of muscle cells.   --The muscle fibers parallel one another and have a striated appearance.   --Cells are branched or unbranched with single nuclei.   --Each fiber contains stacks of many units of contraction and protein filament

Which of the following statements is unique to skeletal muscle? O a) skeletal muscle has striations O b) skeletal muscle is attached to bones O c) skeletal muscle is under voluntary control O d) skeletal muscle is multinucleated O all of the above O b, c, & d but not a

Which of the following happens within the sarcomere during muscle contraction?     The myosin filaments "walk" along the actin filaments bidirectionally towards the Z lines.     The myosin filaments shorten.     The actin filaments shorten.     The H bands and I bands both increase in width.

Place the following steps in the sliding filament theory of muscle cell contraction in the correct order: 1 - B. Depolarization 2 - C. Repolarization 3 - Na+ ion channels open, and Na+ rushes into the cell 4 - CA++ binds to troponin and tropomyosin, and removes them from the binding sites on actin 5 - A. The neurotransmitter is released into the synaptic cleft, diffuses to the sarcolemma, and binds to receptors 6 - b. the sarcomeres shorten, shortening the muscle cell 7 - Troponin and tropomyosin cover the actin binding sites again 8 - Ca++ is released into the cell from sarcoplasmic reticulum and T-tubules 9 - Ca++ is returned to the T-tubules and sarcolemma, using ATP 10 - The muscle cell is ready to contract again 11 - c. ATP releases each myosin head from the actin binding site , which attaches to the next actin binding site 12 - Na+ channels close, and K+ channels opening, allowing K+ to rush out of the cell 13 - The Na+/K+ pump restores the resting potential across the membrane…

The region of the muscle fiber involved in a neuromuscular junction is called the: Group of answer choices Voltage-gated ion channels Synaptic end bulb Synaptic cleft Motor end plate Synaptic vesicle

Complete the following analogies: Troponin is to skeletal muscle as tropomyosin is to smooth muscle Neuromuscular junction is to skeletal muscle as striations is to smooth muscle Oxidative metabolism is to slow twitch fibers as sliding filament theory is to fast twitch fibers if it is wrong let me know what might be the correct answer.

What would happen to muscle function if you ingested a toxin that completely inactivated troponin?  The toxin inhibits its ability to change conformation. How would this affect muscle contraction?

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 to

Choose the incorrect statement about skeletal muscle.   Question 3 options:   Skeletal muscle is made from thousands of muscle fibres running along the length of the muscle.   Each myofibril contains repeating patterns of sarcoplasmsic reticulum, giving muscle tissue its typical striated pattern.   Each individual fibre in a muscle is a single cell containing multiple nuclei.   Within in each fibre, there are longitudinal myofibrils made up from thin and thick filaments.

Researchers are working to understand a rare disease that affects the ability of the muscles to contract. They have identified that the disease is caused by abnormal gene expression leading to a relatively large intracellular space between the T-tubules and the terminal cisternae in the triad, which causes an interruption in the connection between the dihydropyridine (DHP) receptor and the ryanodine calcium channel. Based on this description of the morphology underlying the disease, which of the following problems would you expect in excitation-contraction coupling? An action potential would not be able to be transmitted down the T-tubule. Re-uptake of calcium would be blocked, leading to an increase in intracellular calcium. O The actin binding sites may continue to be blocked by tropomyosin even following an action potential along the sarcolemma. O All of the above. Only B and C.