Ch 2 Chemistry Review Atom- smallest stable units of matter Subatomic Particles: Protons- + charge, nucleus Neutrons- no charge, nucleus Electrons- - charge, outer shells Atomic #- # of protons Atomic Mass- # protons + # neutrons

Ionic Bonds- (ion = charged atom) Atoms lose or gain electrons and become charged Cations=+ Anions=- Ions of opposite charges form ionic bonds Covalent Bonds Atoms share pairs of electrons Strongest bonds Polar=unequal: hydrophilic Nonpolar=equal: hydrophobic Hydrogen Bonds Weak attraction between polar molecules Slightly – end attracted to slightly + end of different polar molecules

Metabolism- all reactions occurring in cells/tissues at a given moment Chemical Reactions new chemical bonds form between atoms or existing bonds are broken Metabolism- all reactions occurring in cells/tissues at a given moment Decomposition- reactions that break down molecule into smaller fragment Ex: hydrolysis- bond is broken and (H & OH) are added to fragments Catabolism- rxns within the body’s cells & tissues, break covalent bond, releases kinetic energy that = work Synthesis- opposite of decomposition, assembles smaller molecules into larger ones Ex: dehydration synthesis- removal of water Anabolism- rxns within the body’s cells & tissues, take energy to create a bond, “uphill”

Enzymes- catalysts, speed up rxns Metabolism- make it possible for our bodies to break down foods without harsh temps. Promote chemical rxns by lowering the activation energy requirements pH- Acidic vs Basic Unregulated pH > break chemical bonds, change the shapes of complex molecules, disrupt cell tissue & functions Regulated by buffers (bicarbonate)- stabilize the pH of a solution by removing or replacing H+ ions Inorganic compounds help regulate pH

Inorganic- H2O, O2, vitamins, electrolytes Organic molecules- C & H, large Monomers- single subunit Polymers- many monomers bond together

1. Carbohydrates C, H, O: (1:2:1) Energy source Ex: Glucose/Fructose > monosaccharide > quick energy Sucrose/Lactose/ maltose > disaccharides > energy Glycogen > polysaccharide > energy storage by liver Cellulose > Starch in plants

2. Lipids C, H, O(small) Form essential structural components of all cells Energy reserves, stored as fats Ex: fatty acids Saturated- each carbon atom in the tail has four single covalend bonds Unsaturated-one or more of the tails has a double bond Eicosanoids: Leukotrienes- coordinate response to injury/disease Prostaglandins- coordinate cell activity, pain receptors Glycerides > fat storage, protection Steroids > cholesterol for plasma membrane, hormone production Phospholipids > plasma membrane formation

3. Proteins Long chains of AA F(x): Support Movement- muscles Transport- lipids, gases, bind to transport proteins Buffering- prevent dangerous changes in pH Metabolic regulation- enzymes Coordination & control Defense- skin, hair, nails, antibodies

Proteins contd Primary- sequence of AA bonded together in a single chain Secondary- hydrogen bonds create either an alpha-helix or pleated sheet structure Tertiary- complex coiling & folding of a secondary protein creating 3D shape Quaternery- 2 or more tertiary proteins associated together to form a protein complex Denaturation: loss of protein structure due to high temp or extreme acids/bases Loss of structure = loss of function Enzymes: Substrates- reactants in enzymatic rxns Active site- where rxn takes place Promote rxns by lowering the activation E requirements

4. Nucleic Acids 1 or 2 long chains that are formed by dehydration synthesis Subunits= nucleotides: pentose + phosphate group + nitrogenous base F(x): make proteins Ex: A,T,C,G- storage or transfer of info DNA- genetic information that controls protein synthesis RNA- performs protein synthesis as directed by DNA ATP- provides cells with energy to perform vital functions

Structure of High Energy Compounds Phosphate group Enzymes capable of catalyzing the rxns involved Suitable organic substrates to which the phosphate can be added ATP > ADP >AMP F(x): quick energy