The correct answer is that "t<span>roponin holds the tropomyosin in place on the actin".
In excitation-contraction coupling, tropomyosin prevents the interaction between actin and myosin in resting muscles. In the event of excitation, there is release of calcium from the sarcoplasmic reticulum wherein the troponin will bind this calcium and will release tropomyosin and expose myosin enabling it to attach to actin and therefore facilitating muscle contraction.</span>
Answer:
Positive charge. They are the opposite of electrons.
The stomach breaks down food , so it has the most acidic substance
True. A protein becomes functional only when it reaches its tertiary shape (3D). It is not necessary for the protein to reach the quaternary stage, but that is just a more complex functioning protein. It really is just two tertiary merged together. Example is red blood cells.
30% of the earth's surface is covered by forests.
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