How did the earliest life come into being, and why did organic matter become single-celled organisms?

After the earth was formed in the universe, there was no life at first. After long-term chemical evolution, that is to say, organic elements in the atmosphere, such as hydrogen, carbon, nitrogen, oxygen, sulfur, phosphorus, etc., are synthesized into organic molecules (such as methane, carbon dioxide, carbon monoxide, water, hydrogen sulfide, ammonia, phosphoric acid, etc. Under the action of various natural energy sources (such as lightning, ultraviolet rays, cosmic rays and volcanic eruptions, etc.). ).

These organic molecules are further synthesized and become biological monomers (such as amino acids, sugars, adenosine and nucleotides).

These biological monomers are further polymerized into biopolymers, such as protein, polysaccharides, nucleic acids, etc. This process is called chemical evolution. After protein appeared, the simplest life was born.

Extended data:

Unicelled organism: an organism consisting of only one cell.

Plants: Terrestrial multicellular eukaryotic animals that can carry out photosynthesis: Generally, inorganic substances cannot be synthesized into organic substances, and they can only feed on organic substances (plants, animals or microorganisms), so they have different morphological structures and physiological functions from plants to carry out life activities such as feeding, digestion, absorption, respiration, circulation, excretion, sensation, movement and reproduction.

Life system: A system that can independently complete life activities is called a life system. From big to small, it is biosphere, ecosystem, community, population and individual, (digestion, respiration and circulation, etc. ) systems, organs, tissues and cells.

Single-celled organisms have no hierarchy of systems, organs and tissues, and cells are individuals; Plants have no system (digestion, respiration, circulation, etc.). ); Viruses are creatures, but not living systems.

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