Answer:
un ser vivo se define por que tiene un periodo de vida
Explanation:
Answer: Over 4 billion years ago
Explanation: The chemical reactions between carbon and water is said to bring about life according to scientists. These reactions builds largely upon four families of chemicals (lipids, carbohydrates, amino acids, and nucleic acids).
However, the actual time of life on Earth has varying speculations from different scientists in fields of study (such as molecular biology, chemistry, oceanography, etc).
Furthermore, microfossils within hydrothermal-vent precipitates dated from 3.77 to 4.28 billion years is presumed to inhabit the oldest record of life on Earth. Hence, which is presumed to have occurred after ocean formation 4.4billion years ago.
Thus, the actual date of the chemical reactions that brought about life is not rigid, but presumed to have occurred over 4billion years ago (according to research).
The answer is the first one
Moves astronauts around
Answer:
cells connecting to each other in colonies and communicating.
Explanation:
Photosynthesis in algae cells
Ecosystems were able to maintain themselves by cycling the
nutrients and energy obtained from external sources. The flow of energy through
a food chain is known as energy flow. At tropical level, solar energy is used by the primary producers to produce organic plants materials through photosynthesis.
