Nucleic Acids Information storage

Nucleic Acids Function: Examples: Structure: store & transmit hereditary information Examples: RNA (ribonucleic acid) DNA (deoxyribonucleic acid) Structure: monomers = nucleotides

Are nucleic acids charged molecules? Nucleotides 3 parts nitrogen base (C-N ring) pentose sugar (5C) ribose in RNA deoxyribose in DNA phosphate (PO4) group DNA & RNA are negatively charged: Don’t cross membranes. Contain DNA within nucleus Need help transporting mRNA across nuclear envelope. Also use this property in gel electrophoresis. Are nucleic acids charged molecules?

Dangling bases? Why is this important? Nucleic polymer Backbone sugar to -PO4 bond phosphodiester bond new base added to sugar of previous base polymer grows in one direction N bases hang off the sugar-phosphate backbone Dangling bases? Why is this important?

Pairing of nucleotides Nucleotides bond between DNA strands H bonds purine :: pyrimidine A :: T 2 H bonds G :: C 3 H bonds The 2 strands are complementary. One becomes the template of the other & each can be a template to recreate the whole molecule. Matching bases? Why is this important?

Passing on information? Why is this important? Information polymer Function series of bases encodes information like the letters of a book stored information is passed from parent to offspring need to copy accurately stored information = genes genetic information All other biomolecules we spoke about served physical or chemical functions. DNA & RNA are information storage molecules. DNA well-suited for an information storage molecule: chemically stable stores information in the varying sequence of nucleotides (the genetic code) its coded sequence can be copied exactly by the synthesis of complementary strands; easily unzipped & re-zipped without damage (weak H bonds) damage to one strand can be repaired by addition of bases that match the complementary strand Passing on information? Why is this important?

Interesting note… Ratio of A-T::G-C affects stability of DNA molecule 2 H bonds vs. 3 H bonds biotech procedures more G-C = need higher T° to separate strands high T° organisms many G-C parasites many A-T (don’t know why) At the foundation of biology is chemistry!!

Another interesting note… ATP Adenosine triphosphate modified nucleotide adenine (AMP) + Pi + Pi + +

Let’s build some DNA, baby!