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Answer:
In the n=1 energy level, the atom has 2 electrons
Explanation:
Electrons orbit the nucleus of an atom in multiple rings (energy levels). The first ring of the electron can only hold 2 electrons. After that, electrons are added to the second ring. Excluding the first ring, all other rings can hold a maximum of 8 electrons.
For example, Oxygen is an atom with 6 electrons. The first energy level contains 2 electrons, and the second energy level contains 4 electrons. The second energy level has room for up to 4 more electrons.
In your example of an atom with 15 electrons, there would be 2 electrons in the first ring, 8 electrons in the second ring, and 5 electrons in the third and final ring.
To summarize, all atoms have a first energy level containing 2 electrons, and all other energy levels can contain 8 electrons. This is true no matter the number of electrons.
Explanation:
Microspheres were spherical bodies with metabolic abilities that could successfully sustain their existence. However they did not contain any genetic material. Which means that they could not replicate or pass off their parts to their successive generations.
But they had no way to evolve since they could not pass off any genetic material to their offspring's. This is why RNA came into existence. RNA enabled an Organism to store its genetic material into nucleic acids, that could be passed on to generations to come. This is also how they could evolve into more complex organisms.
Studies the evolutionary processes that produced the diversity of life on Earth, starting from a single common ancestor.