Nucleic Acids-Information molecules-Storage for information incells-DNA & RNA-Can produce exact copies of themStructures of Nucleic AcidNucleic acids are long polymers of repeating subunits called Nucleotides.-There are 3 components of a Nucleotide:1.A five-carbon sugar2.A Phosphate group (—PO4)3.An organic nitrogenous base-When a nucleic acid polymer forms, the phosphate group of one nucleotide binds to the hydroxyl group of another,releasing water and forming a phosphodiester bond. -Anucleic acid, then, is simply a chain of five-carbon sugar linked together by phosphodiesterbonds with an organic bassprotruding from each sugar.Two Types of Organic Bases:ØPurines – are large, double-ring molecules found in both DNA and RNA;they are Adenine (A) and Guanine (G).ØPyrimidines – are smaller,single-ring molecules; they include Cytosine (C,in both DNA and RNA), Thymine (T, in DNA only), and Uracil (U, in RNA only)Deoxyribonucleic Acid (DNA)-Hereditary material-Has a double helix structure (double stranded)-In each of its steps are complimentary base pairs attracted by hydrogen bonds.Ribonucleic Acid (RNA)-Responsible for protein synthesis-Singe strandedThe Ultimate Face-Off!(DNA vs. RNA)1. DNA contains deoxyribose sugar while RNA contains ribose sugar in which the #2 Carbon is bonded to a hydroxyl group. In DNA, this hydroxyl group is replaced by a hydrogen atom.2. RNA utilizes Uracil in place of Thymine. Uracil has the same structure as Thymine, except that one if its carbons lacks methyl group (—CH3).3. DNA is double stranded while RNA is single stranded4.They obviously has different functionsWhy Do we Need To Transcribe DNA Message?-This allows cell to tell which is the original information storage molecules and which is thetranscriptLipids -Insoluble in water-Most familiar lipids are fats and oils-Have a very high proportion of nonpolar
carbon-hydrogen (C—H) bonds-They don't fold like a protein instead, when placed in water many lipidmolecules will spontaneously cluster togetherand expose what polar groups they have.Phospholipids Form Membranes-Phospholipids are among the most important molecules of the cell, as they form the core of all biological membranes.-An individual phospholipid is a composite molecule, made up of 3 kinds of subunits:1.Glycerol, a three-carbon alcohol, with each carbon bearing ahydroxyl group. It forms the backbone ofthe phospholipid molecule.2. Fatty acids, long chains of C—H bonds (hydrocarbon chains) ending in a carboxyl group (—COOH).Two fatty acids are attached to the glycerol backbone in a phospholipid molecule.3. Phosphate group, attached to one end of the glycerol. The charged phosphate group usually has a charged organic moleculelinked to it, such as Choline, Ethanolamine, or the amino acid Serine.-The phospholipid molecule can be thought of as having a polar “head” at one end (phosphate group) and two long, very nonpolar “tails” at the other.