Action potentials (i.e. nerve impulses) occur in several types of animal cells<span>, called </span>excitable cells<span>, which include </span>neurons<span>, </span>muscle cells<span>, </span>endocrine<span> cells, and in some </span>plant cells<span>. </span><span>It takes around 40 action potentials for a smell sensation to be reported.</span>
Thomas huxley = his findings made the theory of evolutions became widely accepted
Ernst Mayr = the one who proposed Biological species concept
Herbert spencer = found similarities between societies within humans and animal
Stephen Gould = the one who contributed to the study of fossils
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