CLEP Biology Chapter 2 - Chemistry of Life PDF

CLEP Biology: Chapter 2 - The Chemistry of Life September 28, 2024  Matter - Atoms, Elements, Molecules - Chemistry - the study of matter - Elements - substances that cannot be broken down into any other substance - Atom - smallest un...

CLEP Biology: Chapter 2 - The Chemistry of Life September 28, 2024  Matter - Atoms, Elements, Molecules - Chemistry - the study of matter - Elements - substances that cannot be broken down into any other substance - Atom - smallest unit of an element that retains an element’s characteristics https://saintschemistry8.weebly.com/uploads/5/1/9/3/51932861/6a00d83467970453ef017c31cd9043970b-300x200_3_orig.jpg  Matter - Atoms, Elements, Molecules - Parts of an atom - Nucleus - Proton (+1) - Unique number of protons in an atom - Determines atomic number - Neutron (no charge) - About the same number as protons - Electrons (-1) - In uncharged atom, about the same number as protons - Surrounds nucleus Example: Atoms in element X has 4 protons, 4 neutrons, and 5 electrons. What is the net charge of these atoms? https://www.sciencefacts.net/wp-content/uploads/2020/11/Atomic-Nucleus-Diagram.jpg  Matter - Atoms, Elements, Molecules https://images.slideplayer.com/13/3913461/slides/slide_10.jpg  Chemical Bonds - Covalent bonds = strongest chemical bond - Form molecules - 2+ atoms held together by covalently shared electrons - Compound or molecular element https://media.geeksforgeeks.org/wp-content/uploads/20221111091711/CovalentBond.png  Chemical Bonds - Ionic bonds = form when an atom exchances and electron with another atom https://www.chemistrylearner.com/chemical-bonds/ionic-bond  Chemical Bonds - Hydrogen bonds = weakest bonds - Temporarily holds separate molecules together - Responsible for holding complementary DNA strands together https://media.geeksforgeeks.org/wp-content/uploads/20220817125330/HydrogenBondinginWater.jpg Chemical Reactions - Chemical reactions - happen when molecules interact with each other to form 1+ molecules of another type  The Thermodynamics of Chemical Reactions - https://chemistrytalk.org/endothermic-vs-exothermic-reactions/  Properties of Water - “Elixir of life” - Multiple states of matter (solid (ice), liquid (water), gas (water vapor)) - High specific heat (resists change in temperature; needs significant amount of energy in order to change temp) - High surface tension (allows small particles/organisms to rest on surface) - Polar (able to dissolve many types of organic/inorganic substances) https://physics.aps.org/assets/55d93838-bbfa-4264-89cd-5002ca6e4855/e33_1.png  Acids, Bases, and Buffers - When a chemical is dissolved in water … - Acids - donates protons (H+ ions) - conjugate base is what’s left of an acid after it donates a hydrogen ion (H⁺). - Bases - accepts protons (H+ ions) OR donates hydronium ions (OH-) - conjugate acid is what forms when a base gains a hydrogen ion (H⁺) - Neutralization reaction of acidic solution + basic solution → water + salt - Buffer - aqueous combination of weak acid + its conjugate base OR weak base + its conjugate acid https://www.snexplores.org/article/scientists-say-ph Chemical Structure of Organic Compounds - Organic compounds: compounds that contain carbon - Organic molecules: contain Hydrogen, oxygen, nitrogen, sulfur, phosphorous, some metal ions - Monomers: Basic building blocks of biomolecules (example: amino acids). In carbohydrates, the monomers are simple sugars called monosaccharides. - Polymers: Larger molecules formed from repeating units of monomers. In carbohydrates, polymers are chains of sugars. - Monosaccharides: Simple sugars made of 3 to 7 carbon atoms. Example: Glucose (C₆H₁₂O₆), a key sugar used for energy. - Disaccharides: A specific type of carbohydrate where 2 monosaccharides join together. Example: Sucrose (table sugar) = glucose + fructose. - Polysaccharides: Long chains of monosaccharides (3+). Examples: - Cellulose: A structural component in plant cell walls. (Long chain of water-insoluble polysaccharides) - Glycogen: Used by animals for short-term energy storage. (Polysachharide composed of many bonded glucose units) - Isomers: Molecules like glucose and fructose that share the same molecular formula (C₆H₁₂O₆) but differ in the arrangement of their atoms.  Chemical Structure of Organic Compunds Carbohydrates: Organic compounds made of carbon, hydrogen, and oxygen. - The hydrogen to oxygen ratio in lipids is always 2:1. - Examples: sugars, starches - Crucial for energy storage https://www.expii.com/t/monomers-and-polymers-role-importance-10360  Chemical Structure of Organic Compunds Lipids: Organic compounds made of carbon, hydrogen, and oxygen. - The hydrogen to oxygen ratio in lipids is always greater than 2:1. - Examples: waxes, steroids, phospholipids, and fats. - Hydrophobic (do not dissolve in water). - Perform various functions in cells (e.g., structural, energy storage (fats), moisture barriers). https://www.expii.com/t/monomers-and-polymers-role-importance-10360  Chemical Structure of Organic Compunds Proteins: Large unbranched polymers made of amino acid monomers. - Amino acids: cyclic molecules containing carbon, hydrogen, oxygen, nitrogen, and sometimes sulfur or phosphorus. - Amino acids form polypeptides through peptide bonds. - Protein shape determines function; it folds into unique 3D structures. - Enzymes are specialized proteins that catalyze reactions. https://www.expii.com/t/monomers-and-polymers-role-importance-10360  Chemical Structure of Organic Compunds Nucleic acids: Made of nucleotide monomers, each with a five-carbon sugar, phosphate group, and nitrogenous base. - Two types: DNA (deoxyribonucleic acid) and RNA (ribonucleic acid). - Nitrogenous bases include adenine (A), cytosine (C), guanine (G), and thymine (T) for DNA; uracil (U) replaces thymine in RNA. - Nucleotides pair to form the double-helix structure in DNA (Watson-Crick model). https://www.expii.com/t/monomers-and-polymers-role-importance-10360  DNA vs. RNA https://www.thoughtco.com/dna-versus-rna-608191  Complementarity https://www.nagwa.com/en/explainers/636128124616/ Drawing Bohr Diagrams Lewis Structures Polarity Resources: - https://www.khanacademy.org/science/hs-chemistry/x2613d8165d88df5e:states-of-matter/x26 13d8165d88df5e:electronegativity-and-bond-polarity/v/electronegativity-trends