The most appropriate statement that is explaining the effect and cause during muscle contraction is. “The release of calcium ions causes myosin and actin to attach to each other.” The activation of muscles helps in the generation of muscles that send out the signals to the neurons.
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Last option: Preserve an ecosystem
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• The establishment of a bird reservation is a way to preserve an ecosystem because reservation provides suitable environment to organism. A healthy ecosystem means large number of biodiversity.
Answer:
D. Artificial Selection.
Explanation:
Normal people can't breed cats by modifying their DNA, so options b and c are eliminated. Breeding cats for specific traits is not natural, so it is not choice a, either. Instead, selective breeding is d. artificial selection.
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The proportion of mottled fish will
increase over time because of the construction company that dumps a load of
gravel in the bottom of the lake which give it a mottled appearance that made
the mottled fish invisible by their major predator which is the wading bird that hunts them
by sight.