1. There are many conditions for life on the earth, including external factors and internal factors. The following are some key conditions: external conditions: the stability of the sun: the sun provides light and heat and is the main energy source for life on earth. Safe cosmic environment: the stable orbit of the earth protects the earth from the impact of other celestial bodies in the universe.
2. Self-condition: appropriate temperature: the distance between the earth and the sun is moderate, so that the average temperature of the earth's surface is moderate. Formation of the atmosphere: The earth is of moderate mass and volume, which can attract the atmosphere (mainly nitrogen and oxygen) before it forms. Existence of liquid water: water is the foundation of life, and there is a lot of liquid water on the earth.
3. Basic substances of life: biomolecules such as nucleic acid and protein are the material basis of life. These substances may produce a variety of organic substances and biomolecules on the lifeless primitive earth through natural reasons such as chemical reactions.
4. Crustal movement and geological activities: The crustal movement and geological activities of the earth, such as volcanic eruptions and earthquakes, provide the necessary environmental conditions for the emergence of life. Chemical reaction: In the primitive environment, some simple chemical reactions may gradually form more complex organic substances, which are the basis of life.
5. Natural selection and evolution: With the passage of time, natural selection and evolution gradually complicated life forms, and finally formed various creatures we see today.
The importance of life is as follows:
1. Maintain ecological balance: Each biological species plays an important role in the ecosystem. If a species disappears, it may have a far-reaching impact on the entire ecosystem. Promote scientific and technological progress: human research on life has promoted the development of science and technology. For example, advances in genetic engineering and biotechnology are closely related to life sciences.
2. Food and resources: Many living things are human food sources, and plants provide oxygen for the earth through photosynthesis. Spiritual sustenance and cultural symbols: In many cultures, animals and plants are endowed with special meanings and become people's spiritual sustenance and cultural symbols. Aesthetic value: the biodiversity of nature adds endless beauty and charm to our world.