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It is not distinct from that activity; it is that activity. Man makes his life activity itself an object of his will and consciousness. He has conscious life activity. It is not a determination with which he directly merges. Conscious life activity directly distinguishes man from animal life activity. Only because of that is he a species-being.
Life is a quality that distinguishes matter that has biological processes, such as signaling and self-sustaining processes, from matter that does not. It is defined descriptively by the capacity for homeostasis, organisation, metabolism, growth, adaptation, response to stimuli, and reproduction.
The earliest evidence for life on Earth includes: 3.8 billion-year-old biogenic hematite in a banded iron formation of the Nuvvuagittuq Greenstone Belt in Canada; [30] graphite in 3.7 billion-year-old metasedimentary rocks in western Greenland; [31] and microbial mat fossils in 3.48 billion-year-old sandstone in Western Australia.
A life form (also spelled life-form or lifeform) is an entity that is living, [1] [2] such as plants , animals , and fungi . It is estimated that more than 99% of all species that ever existed on Earth, amounting to over five billion species, [3] are extinct. [4] [5] Earth is the only celestial body known to harbor life forms. No form of ...
The history of life on Earth traces the processes by which living and extinct organisms evolved, from the earliest emergence of life to the present day. Earth formed about 4.5 billion years ago (abbreviated as Ga, for gigaannum) and evidence suggests that life emerged prior to 3.7 Ga. [1] [2] [3] The similarities among all known present-day species indicate that they have diverged through the ...
The Holozoa lineage of eukaryotes evolves many features for making cell colonies, and finally leads to the ancestor of animals (metazoans) and choanoflagellates. [ 5 ] [ 6 ] Proterospongia (members of the Choanoflagellata) are the best living examples of what the ancestor of all animals may have looked like.
Eight years after Man's Place, Darwin's Descent of Man was published. In it Darwin faced the same task of persuading the reader of man's evolutionary heritage. He took, in Chapter 1 The evidence of the descent of man from some lower form, an approach which made good use of his vast supply of information on the natural history of mammals.
Two or more atoms is a molecule, like a dioxide. Many small molecules may combine in a chemical reaction to make up a macromolecule, such as a phospholipid. Multiple macromolecules form a cell, like a club cell. A group of cells functioning together as a tissue, for example, Epithelial tissue. Different tissues make up an organ, like a lung.