Biochemistry Review Biology is the study of living things. Organic or Biochemistry is the study of the chemical reactions in living things. What is the smallest unit of matter? An Atom Atoms- What area is positive and what area is negative? The nucleus is positive The electron cloud is negative Where is the mass? In the nucleus Atoms Atomic Number= # of protons Atomic Mass= P+N First Energy Level= can hold .. 2 electrons Second Energy level can hold.. 8 Electrons What is a molecule? A group of the same kind of atom held together with covalent bonds How are ions and isotopes same/different? They are both molecules and the number of protons stays the same, BUT Ions have different charges (different number of electrons) Isotopes have different masses (different number of neutrons) What makes a molecule polar? Uneven sharing of electrons gives the molecule partially negative areas and partially positive areas Give an example of a polar molecule. Water – H20=Oxygen has a negative charge, hydrogen has a positive charge. What is a compound? A substance made of two or more different elements. These elements are held together with ionic bonds. What is the most common element in living things? Carbon It is present in all four of the biomolecules Which biomolecule contains nitrogen? Protein Let’s talk about bonds! What are the three types we have covered? Ionic, Covalent, and Hydrogen bonds A Bond formed when molecules share electrons Covalent Bonds A Bond between two oppositely charged molecules (one positive one negative) Ionic bonds A Weak bond between polar molecules A Hydrogen Bond Four Categories of Biomolecules Proteins Carbohydrates Lipids Nucleic Acids These are very large molecules so we call them Macromolecules! Carbohydrates- What do we know? Ratio of C:H:O is 1:2:1 Monomers are: saccharides-simple sugars Polymers are: polysaccharides- starches Lipids Monomers are glycerol and fatty acids Polymers are Trigycerides- a glycerol with three fatty acid chains Lipids can be fats or oils, They are nonpolar- don’t mix with water Saturated fats are solid (butter, lard) Unsaturated are oils (olive, vegetable) Proteins Monomer is an amino acid (20 types), each amino acid has an R group on its central carbon. Polymers are polypeptides, two or more amino acids bonded together What is the process that builds polymers from monomers? Dehydration Synthesis (synthesize is to make) Remember this process gives off a molecule of …… H20 Breaking down polymers into monomers is called Hydrolysis- “Lysis” is to break What molecule is needed for this to happen? H20 must be present and breaks into its parts to replace the H’s and O pH scale 1-14 What does it measure? The acidity or basicity of a solution 7 is neutral Acids are … Below 7 Bases are … Above 7 This is the end. Best of Luck!