Most living things need oxygen to survive. Oxygen helps organisms grow, reproduce, and turn food into energy. Humans get the oxygen they need by breathing through their nose and mouth into their lungs. Oxygen gives our cells the ability to break down food in order to get the energy we need to survive.
Density is an intrinsic physical property of minerals that relates to the composition of the mineral and to the pattern in which the mineral’s atoms are arranged.
Nucleic acids are biologically occuring polynucleotides in which the nuclotides residues are linked in a specific sequence by phosphodiester bonds.
The two types of nucleic acids are DNA which is double stranded and serves as the usual carrier of genetic information while RNA which is single stranded serves a carriers of genetic information in some viruses only.