DNA and RNA Summary

Genetic Material: DNA and RNA

  • DNA and RNA are nucleic acids.

  • Nucleotides consist of a sugar, a phosphate group, and a nitrogenous base.

  • Polymer of nucleotides is Nucleic Acid, same as proteins are the polymer of peptides and complex carbohydrates are the polymer of monosaccharide's. Composed of C, H, O, N and P atoms

Functions of Nucleic Acids

  • DNA is the genetic blueprint for the organism, encoding information for cell activities.

  • RNA links genetic information from DNA to protein, interacting with protein-synthesizing machinery to produce polypeptides.

DNA vs. RNA

  • DNA: Deoxyribonucleic acid; RNA: Ribonucleic acid.

  • DNA: 2 strands (double helix), deoxyribose sugar. RNA: 1 strand (helix), ribose sugar.

  • Difference lies in the O attached to the 2' Carbon on the sugar.

Nitrogenous Bases

  • DNA: Adenine (A), Thymine (T), Cytosine (C), Guanine (G).

  • RNA: Adenine (A), Uracil (U), Cytosine (C), Guanine (G).

  • A-T and G-C in DNA; A-U and G-C in RNA.

  • Pyrimidines: single ring (U, T, C). Purines: double ring (A, G).

  • C, A, and G are in both DNA and RNA; T only in DNA, U only in RNA.

DNA Facts

  • Human genome: >3 billion nucleotide bases (A, T, C, G).

  • Order contains instructions for making an organism; every three bases code for an amino acid.

  • Estimated 20,000 – 25,000 human genes.

  • 99.9% of nucleotide bases are the same in all people.

  • <2% of the genome codes for proteins; >97% has no known function.

Genes

  • Short DNA segments coding for proteins.

  • Result of a specific sequence of nucleotides.

  • Humans have 23 pairs of chromosomes, one from each parent.

  • Defined as a region of DNA that controls a hereditary characteristic.

DNA Hierarchy

  • Genome (complete genetic information) > Chromosome > Gene > Nucleotide