The motor neuron carries the nerve impulse.
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The nerve impulse reaches the neuromuscular junction.
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Calcium ions release into the myofibrils.
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Myosin and actin protein filaments attach to each other.
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Myosin filaments pull on the actin filaments.
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The sarcomere shortens.
The neurotransmitter (ACh) from motor neurons signals a muscle fiber to depolarize. The depolarization (Na+) will trigger Ca++ release and will initiate contraction by binding to troponin. Myosin pulls the actin strands. ATP sustains the contraction.
Organization, Metabolism, Responsiveness, Movements, Reproduction, Excretion, Digestion, and Respiration.
Answer: A) The resident populations are more likely affected by these threats because of their proximity to shore.
Explanation:
All of these threats are higher in coastal regions.
As contaminants usually reach the ocean through rivers or because of coastal cities, the highest degree of pollution is there. All chemicals will accumulate in this region first, before they disperse into the offshore region. This is also caused by the fact that the coastal waters have a lower volume and surface area than the offshore which results in a higher degree of contamination.
The answer is H. He is mechanically digesting his food.
