DNA of the nucleus. This DNA is circular, which is what is seen in bacteria as well. There are also no introns in this DNA. The DNA in mitochondria is transcribed and code for proteins that are involved in electron transport within the mitochondrion. The DNA double helix can unwind under certain circumstances. Heat, extremes of pH, and certain chemicals will cause denaturation of the DNA molecule. Low salt concentrations, dimethyl sulfoxide, and formamide will all help to denature DNA. DNA can be denatured and will reanneal or come together, coming together to bind in the same way that existed before the molecules became denatured.
TYPES AND FUNCTION OF RNA RNA or ribonucleic acid is extremely similar to DNA. Two major differences are that RNA strands are shorter and are typically single-stranded molecules. RNA is mainly involved in the synthesis of proteins and in the regulation of the translation process. RNA is made from ribonucleotides linked together through many phosphodiester bonds, which is similar to DNA. The four bases are adenine, guanine, cytosine, and uracil. These different aspects of RNA make it less stable than DNA. Even though RNA is single-stranded, it can fold on itself and make bonds with itself; this tends to stabilize the molecule. There are three main types of RNA—each of which has different structures and functions. All of them participate in the translation process. The three main types are messenger RNA or mRNA, ribosomal RNA or rRNA, and transfer RNA or tRNA. Messenger RNA is what gets transcribed as the chemical messenger between DNA and protein synthesis. DNA is quite large and cannot leave the nucleus. For this reason, messenger RNA is made by “reading” genes on the DNA molecule, making an exactly opposite match to the gene, only the structure made is messenger RNA instead of another DNA strand. The entirety of the transcription process happens through the activity of RNA polymerase, which takes the DNA strand and turns it into a complementary strand of RNA. The strand is read from the five-prime end to the threeprime end.
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