Regents Biology Chapter 2 The Chemistry of Life What are living creatures made of? Day 1

AP Biology Atoms, Compounds and Molecules AA tom - Smallest and basic unit of matter. 33 subatomic particles: NNeutron, proton and electron CC ompound – 2 or more different elements chemically combined. EEx: salt, water, carbon dioxide MM olecule – smallest unit of a compound EEx: 2H 2 O = 2 molecules of water

Regents Biology  96% of living organisms are made of: carbon (C) hydrogen (H) oxygen (O) nitrogen (N) Elements of Life CHON!

Regents Biology Molecules of Life  Put C, H, O, N together in different ways to build living organisms  What are bodies made of?  carbohydrates  sugars & starches  proteins  fats (lipids)  nucleic acids  DNA, RNA

AP Biology What macromolecules are used in biology? Think of the nutrients you eat!

AP Biology Carbohydrates  Atoms present – C, H, and O  Function: Major energy source by cells  Structural uses – cellulose, cell receptors  Monosaccharides (monomers) – single sugar units. ex: glucose, galactose, fructose  Disaccharides (polymers) – double sugar units ex: sucrose, lactose, maltose  Polysaccharides (polymers)– more than 2 sugar units. ex: starch, glycogen, cellulose

AP Biology Carbohydrates

AP Biology Lipids FF ats, oils, triglycerides, waxes, and steroids MM olecules made of C, H and O. LL ipid units: 1 Glycerol and 3 Fatty Acids HH ydrophobic and non-polar FF unctions: Insulation, membrane structures, hormones, padding and waterproof coverings. SS aturated – no double bonds, solid animal fats UU nsaturated – one double bond, oils (from plants) *no monomer units here! They do not repeat

Proteins PP olymers containing: NN, C, H and O. AA mino acids = monomers AA Peptide bond holds 2 amino acids together. FF unctions: Control the rate of reaction, regulate cell processes, form bones, muscles, fibers, hair/nails, transport substances to fight disease.

Nucleic Acids PP olymers – containing H, O, N, C, and P NN ucleotides (monomers) --- sugar, phosphate, and a nitrogenous base FF unction: Stores and transmits hereditary information TT ypes: DNA and RNA

 You Are What You Eat! You Are What You Eat! Macromolecules

Regents Biology How do we make molecules? We build them! Day 2

Regents Biology  Small molecules = monomers  Bond them together = polymers Building large organic molecules

Regents Biology Building important polymers sugar – sugar – sugar – sugar – sugar – sugar nucleotide – nucleotide – nucleotide – nucleotide Carbohydrates = built from sugars Proteins = built from amino acids Nucleic acids (DNA) = built from nucleotides amino acid amino acid – amino acid – amino acid – amino acid – amino acid –

Regents Biology How to build large molecules  Dehydration Synthesis  Taking water out to put the monomers together  building cells & bodies

Regents Biology Example of dehydration synthesis amino acidsprotein amino acids = building block protein = polymer  Proteins are synthesized by bonding amino acids

Regents Biology How to take large molecules apart  Hydrolysis  taking big molecules apart using water  getting raw materials  for synthesis & growth

Regents Biology Example of hydrolysis starchglucose  Starch is digested to glucose

AP Biology Enzymes Special proteins that make our processes run faster…. Day 3

AP Biology Chemical Reactions TT he changing of one set of chemicals into another set of chemicals RR eactants start the reaction. PP roducts are produced by the reactants. Ex: CO 2 + H 2 O H 2 CO 3 AA ctivation energy: amount of energy needed to get a reaction started Reactants (before arrow) Products (after arrow)

AP Biology

Enzymes (biological catalysts) AA catalyst is a substance that speeds up a chemical reaction by lowering the required activation energy to run the reaction. EE nzymes are very specific for certain chemical reactions. ex: lactase works only on lactose! EE nzymes are never used up, can be reused. TT o Denature an enzyme/protein = To Destroy it

Enzyme Names 1.End in “–ase” 2.Ex: sucrase, lactase Enzyme Action 1. Enzymes provide a site where substrates (reactants) can react using less energy by lowering the activation energy Enzymes (biological catalysts) Enzymes & Substrates = Lock & Key

AP Biology Reaction pathway without enzyme Activation energy without enzyme Activation energy with enzyme Reaction pathway with enzyme Reactants Products Effects of Enzymes

AP Biology How Do Enzymes Work? SS ubstrates = The reactants the enzyme works on. AA ctive sites = place on enzyme where reactants bind.

Enzyme Regulation  Enzyme activity can be altered by changing working conditions. Ex: pH and temperature  Cells can make other proteins to turn “on or off” an enzyme.