The immanent purpose is an intrinsic property of living beings, without it, they would not exist. Consider the autonomous function units and their components: organs, tissues, isolated cells, as well as other properties such as nutrition, body defense, growth, reproduction, to which they are subject at the end. When it comes to these properties, biologists do not argue; but if you pronounce the word purpose, there is a public outcry. Probably because they do not distinguish the purpose of fact or immanent, the trascendental purpose. Of the latter, the biologist has little or nothing to say; it is a matter of metaphysics.