Answer:
Step 1 of the formation of the solar system. the solar nebula collapses.
Step 2 of the formation of the solar system. rotating protostellar disk.
Step 3 of the formation of the solar system. center of nebula fusion begins, star is born.
Step 4 of the formation of the solar system
Explanation:
Answer:
It could not exist without bacteria.
Centriols are the ones responsible
But roughly 2.45 billion years ago, the isotopic ratio of sulfur transformed, indicating that for the first time oxygen was becoming a significant component of Earth's atmosphere, according to a <span>2000 paper in Science</span>. At roughly the same time (and for eons thereafter), oxidized iron began to appear in ancient soils and bands of iron were deposited on the seafloor, a product of reactions with oxygen in the seawater."What it looks like is that oxygen was first produced somewhere around 2.7 billion to 2.8 billon years ago."It looks as if there's a significant time interval between the appearance of oxygen-producing organisms and the actual oxygenation of the atmosphere."
DNA replication only happens during meiosis because the chromosome number of the species remains the same from one generation to the next, the chromosome number of germ cells must be reduced by half during meiosis. To achieve this feat, meiosis, unlike mitosis involves a single round of DNA replication followed by two rounds of cell division.
