Hydrogen is the lightest element on the periodic table of elements. Hydrogen gas is always bonded to itself or something else to fill its outer shell. That is why hydrogen gas is represented as H2. Hydrogen<span> is odorless, colorless, and tasteless; therefore, it is undetectable by human senses.</span>
Plants absorbs inorganic ions such as carbon dioxide by the process of gas exchange and water by the process of osmosis which converts into glucose and oxygen in the presense of sunlight and chlorophyll.Light is absorbed by the chlorophlasts present in green leaves.
The precambrian era makes up about 90% of the earths history, but there was little to no living organisms at the time other than microscopic ones. The first eukaryotes were found in the cambrian period after the precambrian period, not only that but at the end of the precambrian era in the Proterozoic era there was a mass extinction of about 70-80% of all living organisms
