Answer:
Fossil records provide evidence of an increase in animal species at the same time that atmospheric oxygen levels increased.
Explanation:
A huge diversification among animal species occurred with the increase in the levels of atmospheric oxygen. The reason why the number of species increased drastically was that a whole new world opened up, the land. The land was open for exploitation and taking over, with every single niche free, so animals diversified and filled in pretty much all of the niches. The fossil records give us clues when this happened, as from only microorganisms there is a sharp rise in complex animals, coinciding with the increase of oxygen levels.
If it wasn't for the increase of atmospheric oxygen though this wouldn't have been possible. The oxygen in the atmosphere enabled animals to breathe on land. Also, it cooled off the global temperatures which were too high before the increase of atmospheric oxygen, making them suitable for life. And last but not least, the atmospheric oxygen resulted in the formation of the ozone layer, a layer that started to act as protection from the UV rays.
Answer:
They make it themselves! Plants are called autotrophs because they can use energy from light to synthesize, or make their own food source. Rather, plants use sunlight, water, and the gases in the air to make glucose, which is a form of sugar that plants need to survive.
For the answer to the question above, <span>I assume you are referring to DNA replication which takes place in the synthesis (S) phase of the cell cycle shortly before G2. If that doesn't happen, the cell will not proceed to G2 and eventually mitosis, thus division will not complete. </span>The new cells would have an incorrect amount of chromosomes.
Answer: If this doesn't help just let me know
The abiotic factors will define which organisms are able or not to live in a specified place. The living organisms will constitute the biotic factors, which define if and how can an organism live in a specified environment. So, the abiotic factors are controlling the biotic factors of an environment.