BIOCHEMISTRY CHAPTER 2

ATOMS the smallest unit of an element. Inside the Nucleus Protons- Positive Charge Neutrons – No Charge Surrounding the Nucleus Electrons – Negative Charge

MOLECULE A molecule is formed when two or more atoms join together chemically. EX: O 2 (Oxygen Gas)

COMPOUNDS A compound is a molecule that contains at least two different elements. All compounds are molecules but not all molecules are compounds. EX: H20 (Water)

CHEMICAL REACTIONS Energy is absorbed or released, supplying energy for the organism. When one or more substances is changed into a new substance by breaking and forming new bonds. Ex. 2 H 2 + O 2 2 H 2 O (Reactants)(Products)

HOMEOSTASIS The body must stay in balance Enzymes help maintain homeostasis EX: Temp, PH, Water Conc.

ACIDS, BASES AND PH Acids: lose Hydrogen H+ in water Ex: Orange juice,vinegar and lemons Bases: loses Oxygen and Hydrogen in water OH Ex: Soap, egg whites and baking soda pH: Concentration of Hydrogen in solution, scale of 0-14

MACROMOLECULES Monomer  simple building block Polymer  large complex molecule made of many monomers Polymers are made from monomers

4 MAIN POLYMERS FOUND IN LIVING THINGS (YOU ARE WHAT YOU EAT) Carbohydrates Lipids Phospholipids Nucleic Acid DNA: Deoxyribonucleic Acid RNA: Ribonucleic Acid Proteins Amino Acids Enzymes

CARBOHYDRATES Group of chemicals that includes sugars, starch and cellulose. Used for short term energy storage Simple sugars are the easiest substance for your body to breakdown. Stored as Glycogen, in muscles if not used quickly

CARBOHYDRATES 3 Types 1.Monosaccharide (one sugar) 2.Disaccharide (two sugars) 3.Polysaccharide (many sugars) Ex: Plant starch or animal glycogen Consist of C, H, and O in a 1:2:1 ratio Example: Glucose (C 6 H 12 O 6 )

one monomer of sugar simplest carbohydrate Example: Glucose (C 6 H 12 O 6 )

Two Monosaccharides covalently bonded Examples: sucrose lactose fructose glucose glucose galactose

Straight or branched chains of many sugar monomers Potato is a plant stored starch Animals store glycogen, which is produced in the liver or muscle Cellulose is a non-digestible carbohydrate, the most abundant molecules on earth. Ex: Pencils, Paper, Wood.

LIPIDS Fats, Oils, Waxes, Phospholipids, and Steroids.  Used for long term energy storage  Waxes act as a water repellant  Keep leaves from drying out  Make ducks feathers waterproof  Fats act as an insulator

No double bonds Found in animal products Solid at room temp Contain one or more double bonds Found in plant products Liquid at room temp

PHOSPHOLIPIDS Lipid that forms membrane of the cell Helps control movement in and out of the cell

Lipids with no fatty acids Made up of 4 carbon rings EX: Cholesterol, Testosterone, Estrogen Steroid back bone

Large molecules that contain hereditary information Examples: DNA, RNA Chemical Make-up Phosphate: PO 4 Sugar: C 5 H 10 O 5 Nitrogen base: C 5 H 5 N 5

PROTEINS Large complex molecules composed of smaller units called Amino Acids ( AA)  Made from combinations of 20 different AA  Different Amino Acid combinations produce different Proteins. Enzymes are a form of protein that help control chemical reactions.

Proteins that act as catalysts,Speed up rate of reaction, by making atoms move faster Any Substance that the enzyme works on

HOW ENZYMES WORK 1) Enzymes attach to substrate (whatever it is working on) 2) Chemical bonds are formed or broken in the substrate 3) Products of substrate are released 4) Enzyme goes back and grabs another substrate, and continues this process until the subtarte is all broken down Enzymes & substrates fit together like a Lock & KeyEnzymes & substrates fit together like a Lock & Key

End in “ase” Work with only certain substrates Lactase breaks down Lactose does not get used up Speed up reaction by lowering activation energy; (Energy needed to make reaction happen)

ENZYMES CAN BE DESTROYED OR DENATURED BY HIGH TEMPERATURES  THE HIGH TEMPERATURES CHANGE THE SHAPE OF THE ENZYME Why high fevers can kill us Cooking veggies is bad because we lose good enzymes  OTHER FACTORS THAT EFFECT ENZYMES: pH Substrate Concentration Enzyme Concentration