Chemical Bonding Why do atoms form bonds?

Atoms form bonds to become more…

How does an atom become stable? Atoms become stable by having their outer energy level filled with electrons This is accomplished by forming a bond with another atom

Formation of Chemical Bonds: Bonds are formed in the following ways: Atoms can lose or gain electrons (results in an ionic bond) Atoms can share electrons (covalent bond) Compounds are formed as a result of these bonds Formation of an ionic bond between sodium and chlorine

Organic Compounds (biomolecules) Compounds that contain carbon Hydrogen, oxygen, nitrogen, phosphorus and sulfur can also be found in organic compounds A lipid (a.k.a. fat)

Why Carbon? Carbon can form more bonds than any other element (4) This property allows carbon based molecules to be quite large and diverse

6+ Carbon Atom 4 unpaired electrons = 4 bonds formed

Types of bonds CC Single Bond (one pair of e - shared) CC Double Bond (2 pairs of e - shared) CC Triple Bond (3 pairs of e - shared)

Types of Organic Compounds Carbohydrates Lipids (Fats) Proteins Nucleic Acids (DNA, RNA)

Composition of Organic Compounds Organic compounds are made of monomers - individual subunits Many monomers form polymers - larger molecules

Glycerol (monomer) 3 Fatty acids (monomers) Lipid (polymer)

Two amino acids bonded together (dipeptide - polymer) Amino acid (monomer)

Nucleic Acid (polymer) Nucleotides (monomers)

Nucleotide Five carbon sugar Nitrogen base Phosphate group

Types of biochemical reactions: -Breaking apart a polymer into smaller molecules (like monomers) by adding water (ex. digestion) +WATER + *(See figure 6.18 on pg. 159 of your book)

Types of biochemical reactions: -combining two smaller molecules into a larger molecule by removing water + + WATER *(See figure 6.18 on pg. 159 of your book)

Enzymes - protein molecules that regulate chemical reactions in the body

Chemical Reactions A +BC+D reactantsproducts C 6 H 12 O O 2 6 CO H 2 O glucose Atoms of reactant(s) are rearranged to form the product(s) Example of biochemical reaction: Cellular Respiration

Enzymes act as Catalysts Catalysts speed up chemical reactions without being used up or changed during the reaction

How do Enzymes Speed up Chemical Reactions? The energy required to get a chemical reaction started is the activation energy Enzymes work by lowering the activation energy to speed up the reaction

enzyme Substrate (nutrient, drug, chemical, etc) Active site - area of enzyme where reaction takes place Enzyme- substrate complex End product (Example of hydrolysis reaction) enzymes

Factors affecting the rate of a reaction Amount of enzyme present Amount of substrate present Temperature and pH

Enzyme Denaturation Enzyme is shown in yellow Blue molecules are the substrate Heat or pH change Reaction takes place normally No reaction occurs (active site is damaged and substrate no longer fits)