Biol- M 200 1st Edition Lecture 4Outline of Last Lecture I. Taxonomy- naming systemsOutline of Current Lecture II. MicrobesIII. AtomsIV. Chemical bondsV. MacromoleculesVI. DNA vs. RNACurrent LectureAtoms- Definition: the smallest chemical unit of matter- Protons: positively charged atoms- Neutrons: Negatively charged- Electrons: negatively charged subatomic particles.o Valence electrons: an atoms outermost electronsChemical Bonds- Covalent bond: sharing of a pair of electrons by two atoms- Non-polar covalent bonds: pair of electrons is nearly equally shared between two atoms- Polar covalent bonds: electrons spend more time around the more electronegative of two atoms. (unequal sharing of electrons)- Ionic bonds: giving up of electrons from one atom to another.- Hydrogen bonds: a weak ionic bond between hydrogen and an atom with an electronegative value.Macromolecules- Definition: building blocks of cells. - Phospholipidso Similar to fats, but contain only two fatty acid chains instead of three.- Polysaccharideso Polymers composed of tens, hundreds, or thousands of monosaccharides. These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.- Proteinso Most complex organic compound, which are composed of carbon, hydrogen, oxygen, nitrogen and sulfur. Polysaccharide function- Energy source (carbohydrates)- found out in the environment.- Structural component: alpha or beta, branched or unbranched.- Sugar cell on cell surface can identify microorganismsEnzymes- Very specific shapes so they only bind to their specific substrate(s)- “like a lock and key”- Then change shape to properly position and stress the substrate to start the reaction.Nucleic Acids- Get their name due to isolation from the nucleus of eukaryotic cells.- Bacteria and archaea have nucleic acids too- Carry genetic information- Composed of nucleotides linked by covalent bonds between the phosphate of one nucleotide and the sugar of the next. Phospholipids- Composed of a hydrophilic (polar) “head”- which is composed of glycerol and a phosphate group, and two hydrophobic (nonpolar) fatty acid “tails”- Hydrophilic: associates with water- Hydrophobic: avoids water- Similar to fats, but contain only two fatty acid chains instead of three.DNA and RNA- Unbranched polymers of nucleotides- Composed of deoxyribose or ribose sugars, ionized phosphate, and a nitrogenous base.- Five bases include: adenine, guanine, cytosine, thymine, and uracil.- RNA uses uracil nucleotides instead of thymine nucleotides. - Adenine always pairs with Thymine- Cytosine always pairs with