DNA stands for deoxyribonucleic acid. RNA stands for ribonucleic acid. Whereas DNA contains deoxyribose, RNA contains ribose. Unlike DNA, which holds together through hydrogen bonds, RNA does not employ hydrogen bonding. DNA has the following nucleotide bases: adenine, cytosine, thymine, and guanine. Three of RNA's nucleotide bases are the same: adenine, cytosine, and guanine. In RNA, thymine is replaced with uracil. Finally, DNA only exists in the nucleus as nuclear DNA or in mitochondria as mitochondrial DNA. RNA travels back and forth from the nucleus to the ribosomes as a part of protein synthesis. There are two types of RNA: Messenger RNA (mRNA) and Transcription RNA (tRNA).<span />
Oxygen is a chemical element – a substance that contains only one type of atom. Its official chemical symbol is O, and its atomic number is 8, which means that an oxygen atom has eight protons in its nucleus.
The number of Golden Toads people saw declined from 1,500 to zero in such a short period of time. Scientists suspect that conditions related to climate change was the reason for their extinction
