BIOCHEMISTRY

Outline Macromolecules of life Assemble/disassemble 1. Carbohydrates (Glucose) Monosaccharide Polysaccharide 2. Lipids (glycerol + 3 fatty acids) 3. Proteins (amino acids) Nucleic acids (RNA/DNA) Enzymes

MACROMOLECULE SUBUNIT FUNCTION EXAMPLE Carbohydrates Starch / Glycogen Glucose Energy storage Potatoes Cellulose Cell walls Paper Chitin Modified Glucose Structural Support Crab shells Lipids Fats Glycerol, 3 fatty acids Butter, soap Phospholipids 2 fatty acids + phosphate Cell membranes Lecithin Steroids Four carbon rings Membranes, hormones Cholesterol Estrogen Terpenes Long carbon rings Pigments, structural Carotene Rubber Proteins Globular Amino acids Catalysis, transport Sucrase Hemoglobin, Structural Support Hair, silk Nucleic Acids DNA Nucleotides Encodes genes Chromosomes RNA Needed for gene expression Messenger RNA

Assembling Macromolecules

Disassembling Molecules

Carbohydrates “energy storage” 2 atoms - Hydrogen 1 atoms - Oxygen for every 1 atoms - Carbon saccharide (sugar) 3-7 carbon = mono 3-7 x 2 = di Many = poly

Disaccharides Glucose + glucose = maltose Glucose + galactose = lactose Glucose + fructose = sucrose

Polysaccharides Starch Glycogen Cellulose

Lipids “energy storage & cell membranes” Structure Glycerol + 3 fatty acids (100 fatty acids)

Types Saturated = no carbon double bonds = 1 mono, = 2 or > poly (Oleic acid found in mammalian tissue) Unsaturated = carbon double bonds Properties Insoluble in water Unsaturated = liquid (olive oil) Saturated = solid (margarine) Functions 2.25 more energy/g .: used as energy storage: triglycerides Cell membranes : phospholipids Steroids (4 carbon rings): Cholesterol synthesizes hormones, bile, vitamin D3

Proteins Structure Amino acids (11/20 made in the body)

Enzymes Catalyst: speeds up chemical reactions in the body, but remains unused in the reaction. they lower the amount of energy required to initiate a reaction Enzyme: is a protein catalyst the speeds up the reaction by lowering the activation energy 1000’s usually end in ‘ase’

Structure Active site that is specific to the substrate ( the molecule being disassembled) When the substrate binds to the active site, it wakens the bond, using water to disassemble (hydrolysis)

Factors that Influence Enzyme action Temperature most function best at 35oC – 40oC pH optimum 6 -8 pepsin digests proteins in stomach at pH 2 Activators : chemicals that promote the change of the enzyme’s shape in order for catalyst to occur Inhibitors : a chemical that binds the enzyme and shuts down enzyme activity 1. Competitive: occupies the active site 2. Noncompetitive: attaches and changes its shape is

Nucleic Acids Types DNA : deoxyribonucleic acid RNA : ribonucleic acid Function Information storage Encodes genes for protein synthesis Structure long polymers of nucleotides

3. An organic base (Nitrogenous base) Nucleotides 3 Structures: 1. A five carbon sugar 2. A phosphate group (PO4) 3. An organic base (Nitrogenous base) Adenine Guanine Thymine Cytosine Uracil (RNA only)

Homeostasis “The tendency of the body to maintain a relatively constant internal environment.” (McGraw-Hill, 2006) Sensor Stimulus Control centre Effector