The distance between 1 and 7 spans a sarcomere correspond the structure at B is covered by the perimysium.
<h3>What is the smallest contractile unit within skeletal muscle?</h3>
A sarcomere comprises the segment between two consecutive Z lines and is the contractile unit of the muscle fiber, as it is the smallest portion of the muscle fiber capable of contraction and distension.
In this case, the distance between points 1 and 7 has the smallest structure of a skeletal muscle and corresponds to figure B.
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C. Single events or several causes working together to produce extinction in a short period is referred to as mass extinction.
<span>Example:
</span><span>Destruction of forests, mountains, and bodies of water to satisfy human needs result to the imbalance of nature which also give rise to global warming.
</span><span>Animals and plants have lost their habitats. They lost their means to live. They lost their food sources and they suffer and die because of humans irresponsible acts.</span>
Different types of species
