Nucleic Acids

Nucleic Acids

• Nucleic acids are macromolecules composed of nucleotides as monomers.
• They are crucial for the continuity of life, carrying genetic information and instructions for cellular functioning.
• Nucleic acids serve as blueprints for protein synthesis in cells.
• They are the hereditary material in cells, responsible for passing genetic information from reproducing cells to their offspring.

DNA and Nucleic Acids

• DNA is the genetic material found in all living organisms, located in the nucleus of eukaryotes and in chloroplasts and mitochondria, and is not enclosed in a nucleus in prokaryotes.

Structure of Nucleic Acids

• A nucleotide is the building block of nucleic acids, consisting of a nitrogenous base, a sugar molecule, and one or more phosphate groups.
• A nucleoside is a compound consisting of a nitrogenous base and a sugar molecule, lacking the phosphate group(s).
• Nucleotides are named based on the nitrogenous base (e.g., Adenylic acid) or the number of phosphate groups (e.g., Adenosine monophosphate (AMP), Adenosine diphosphate (ADP), or Adenosine triphosphate (ATP)).
• Nucleosides are named based on the nitrogenous base (e.g., Adenosine, Guanosine, Thymidine, Cytidine, Uridine).

Denaturation of DNA

• Denaturation of DNA is the loss of helical structure of DNA as the temperature increases, resulting in the separation of DNA strands.
• Denaturation of DNA is measured using a spectrophotometer, based on the fact that nucleotide bases absorb light in the ultraviolet (UV) range.
• The melting curve of DNA is obtained by plotting the absorbance values with increasing temperature.

RNA

• RNA (ribonucleic acid) is involved in protein synthesis.
• Types of RNA include messenger RNA (mRNA), transfer RNA (tRNA), ribosomal RNA (rRNA), and microRNA.
• mRNA carries protein information from the DNA in a cell's nucleus to the cell's cytoplasm, where the protein-making machinery reads the mRNA sequence.
• tRNA acts as a temporary carrier of amino acids, bringing the appropriate amino acids to the ribosome based on the mRNA nucleotide sequence.