The cyanobacteria changed the composition of the earth’s atmosphere by evolving oxygen in what is referred to as the Great Oxygenation Event. This also allowed the ozone to be formed and block off most of the UV rays that are destructive to genetic material. Life was, therefore, also able to exist on land other than in water.
Answer:
A chemical element is a type of atom with the same number of protons in their <u>atomic</u> nuclei.
Explanation:
For an example, the atomic number of Chlorine is 17, and there is 17 protons in Chlorine.
If you have any questions feel free to ask in the comments.
<span>A centimeter is 100 times smaller than one meter (so 1 meter = 100 centimeters). A dekaliter is 10 times larger than one liter
(so 1 dekaliter = 10 liters). Here is a similar table that just shows
the metric units of measurement for mass, along with their size relative
to 1 gram (the base unit).</span>
